Contents 1 DLC and a-C:H films 3 1.1 Introduction............................................ 3 1.1.1 Kiilisch99-book [?].................................... 3 1.1.2 DLC22 [?]......................................... 3 1.1.3 hydrocarbons....................................... 3 1.2 Overview about papers...................................... 3 1.3 IR bands ............................................. 4 2 CNX films 5 2.1 related chem. compounds.................................... 5 2.1.1 Urotropine ........................................ 5 2.1.2 pyridine.......................................... 5 2.1.3 polyacronitrile ...................................... 5 2.2 nanotubes............................................. 6 2.2.1 Lai03 ........................................... 6 2.2.2 ChenOl .......................................... 6 2.2.3 HammerOl ........................................ 7 2.2.4 Ref. 17 in HammerOl - sehnat! ............................ 7 2.2.5 Marton94......................................... 8 2.3 FTIR and XPS.......................................... 8 2.3.1 Mutsukura99, TSF, cn/mutsukura99.pdf........................ 8 2.3.2 JelinekOO, TSF...................................... 9 3 Si-related compound 11 3.1 Analysis of silicones, chapter 10 (FTIR), D. R. Anderson .................. 11 3.1.1 Si-H............................................ 11 4 Si-nitrides, carbides and carbonitrides 13 4.1 About effort in Si-C-N compounds............................... 13 4.1.1 si-based_hard/sicn/Smirnova03 [?] ........................... 13 4.1.2 si-based_hard/sicn/Peng01 PengOl........................... 13 4.2 FTIR of silicon nitrides ..................................... 13 4.2.1 book - Silicon Nitride in Elecronics, V. I. Belyi et al., Elsevier 1988 [?]....... 13 4.2.2 si-based_hard/sin/lucovsky83 [?] ............................ 14 4.2.3 si-based_hard/sin/tsu86 [?] ............................... 14 4.2.4 ftir/lanford78 [?]..................................... 14 4.2.5 Materials Science of Carbides, Nitrides and Borides, ed. Y.G. Gogotsi, R.A. An-drievski, NATO Science Series Vol. 68......................... 14 4.2.6 si-based_hard/sin/lattemann03 [?] ........................... 14 4.2.7 si-based_hard/sin/parson91 [?] ............................. 15 4.3 FTIR on Si-C-N films ...................................... 15 4.3.1 papersl/si-basedJiard/sicn/peng01 [?]......................... 15 4.4 FTIR on Cl-related films..................................... 15 4.4.1 ftir/Cl-related/Upadhyay04 [?]............................. 15 1 o Urganosiloxanes 17 5.1 Overview about papers...................................... 17 5.2 Results on plasma deposition from HMDSO.......................... 18 5.2.1 VanOoij97-HMDS04 [?]................................. 18 5.2.2 Alexander96-HMDS07 [?]................................ 18 5.2.3 Alexander97a-HMDSO10 [?] .............................. 18 5.2.4 Tien72-HMDS011 [?] .................................. 19 5.2.5 chybi!-HMDS014 [?]................................... 19 5.2.6 Aumaille00-HMDSO19 [?]................................ 19 5.2.7 Ito-HMDSO20 [?] .................................... 19 5.2.8 P0II93-HMDSO2I [?]................................... 20 5.2.9 Lamendola97-HMDS016 [?]............................... 20 5.2.10 Vallee97 [?]........................................ 20 5.3 Application of HMDSO films.................................. 20 6 Organosilazanes 21 6.1 Overview of FTIR and XPS on HMDSN............................ 21 6.1.1 SeekampOO (paper3/hmdsn)............................... 21 6.1.2 Baraton98 (paper3/hmdsn)............................... 21 6.1.3 Pecheur99 (paper3/hmdsn)............................... 21 6.1.4 Fainer03 /papers/hmdsn................................. 22 6.1.5 Gengenbach99 /papers3/hmdsn............................. 22 6.1.6 Grafting with HMDSN - citation? ........................... 23 6.1.7 Ungureanu03 (papers3/hmdsn)............................. 23 6.1.8 Tanaka98......................................... 23 6.1.9 Fainer03 (papers/hmdsn)................................ 23 7 XPS - summary 25 7.1 CNX films............................................. 25 7.2 Summary tables ......................................... 25 7.3 My fit of XPS on HMDSO and HMDSN APG films...................... 29 8 Infrared absorption - summary 31 8.1 Good papers specific to FTIR.................................. 31 8.2 Summary tables ......................................... 31 Bibliography 37 Chapter 1 DLC and a-C:H films 1.1 Introduction 1.1.1 Kulisch99-book [?] Carbon can exist in a vast variety of crystalline and, especially, amorphous modifications. The most important crystalline phases are diamond and graphite that are classical examples of sp3 and sp2-bonded carbon materials, respectively. In contrast to the tetrahedral sp3-bonded diamond, the sp2-bonded graphite has no analog with the other elements of group IV (Si, Ge and Sn) [?], [?]. The reason can be found in the electronic structure of the core of the elements of the first?? row of the periodic table [?], which consists of s-electrons only and contains no p-electrons. Any p-electrons in the core have a repulsive effect on p-valence electrons, forcing them into bonds with neighboring atoms [?]. This means that sp2 hybridization takes place only for elements of the first row. The ability to form double and triple bonds, however, is (besides the ability to form long chains and cyclic compounds) responsible for the immense variety of organic chemistry. The number of possible amorphous carbon films, considering the nature of bonding, composition and structure, is very high. This is especially true if the consideration also includes hydrogen containing films and if, in addition, classical polymers such as polyacetylene (-CH-)n and polyethylene (-CH2-)n are taken into account. This variety of possible structures corresponds to a extreme variation of film properties, which ranges from soft to superhard. A classification of the various types of (hydro)carbon layer can be performed through their hydrogen content, on the one hand, and their density [?] or the fraction of sp3 bonds, on the other hand. 1.1.2 DLC22 [?] DLC films contain both the tetrahedral C-C bonding configuration (sp3), as in diamond, and trigonal bonding configuration (sp2), as in graphite. Depending on the relative fractions of the sp3 and sp2 contents in DLC, the properties of the hardness, optical transparency, smoothness, and chemical inertness vary over a wide range. Therefore, the determination of the sp3/sp2 ratio is a very important issue in characterizing carbon films. The characteristic bonding configuration of hydrogenated DLC films have been studied using infrared spectroscopy [?], 1.1.3 hydrocarbons methane CH4, ethane C2H6, ethylene C2H4, acetylene C2H2 1.2 Overview about papers acetylene: DLC5 theory of bonds: DLC7 bandgap: DLC10 IR spectra: DLC1, DLC4, DLC5 3 -L.o ísx, uaiius band No. configuration predicted freq. observed freq. observed FWHM [cm 1] [cm 1] [cm 1] 1 sp^H 3305 3300 44 2 sp2CH (arom.) 3050 3045 68 3a sp2CH2(olef.) 3020 - - 4 sp2CH(olef.) 3000 3000 78 5a sp3CH3(asym.) 2960 - - 3s sp2CH2(olef.) 2950 - - 6a sp3CH2(asym.) 2925 2920 ? 7 sp3CH 2915 2920 88 5s sp3CH3(sym.) 2870 - - 6s sp3CH2(sym.) 2855 2850 78 Table 1.1: C-H stretch absorption bands [DLC4]. Predicted are taken from [2], [3]. Di- and trihydrogen bands are doublets with a "symmetric" (s) and "antisymetric" (a) vibration. Determination of the absorption coefficient and the optical band gap is based on transmittion and reflection spectra [1]. Deposition of films described in [?], [4]. The bonding type (sp3, sp2 and sp1) can be determined by the spectroscopy of the infrared vibrations of CH, CH2 and CH3 groups. Chapter 2 CNY films 2.1 related chem. compounds 2.1.1 Urotropine Urotropine (CeHi2N4) also called hexamethylenetetraamine (HMTA) contains the nitrogen and carbon atoms in positions closely resembling those in the predicted /?-C3N4. The difference between this molecule and a subnanometer size crystallite of /3-C3N4 is mainly that carbon dangling bonds are hydrogen terminated, altough the nitrogen atoms in urotropine are in tretrahedral, rather than trigonal sites. [Marton94] Note, in XPS of urotropine Cls should be composed from two peaks C-H and C- N (sp3). Nobody gives both positions! Table 2.1: FTIR active modes based on theoretical calculations in [1] /enumber [cm x] wavenumber [cm x] bonds experimental theoretical 2955 2960 C-H stretch 2919 2914 C-H stretch 1456 1458 CH2 scissors 1370 1368 CH2 wag 1240 1243 CH2 rock 1007 1009 N-C stretch 812 825 N-C stretch 673 677 N-C-N bend 512 504 N-C-N wag ChenOl: For urotropine [21 and 22], the C Is binding energy is 286.9 eV and N Is is 399.4 eV. References: 1) Vibrational frequencies and structural determinations of hexamethylenetetraamine, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 58, Issue 7, May 2002, Pages 1347-1364 James O. Jensen =1 papersl/cn/related.struct/jensen02.pdf 21) D. Marton, K.J. Boyd, A.H. Al-bayati, S.S. Todorov and J.W. Rabalais. Phys. Rev. Lett. 73 (1994), p. 118. 22) Mansour and S. Ugolini. Phy. Rev. B 47 (1993), p. 10201. 2.1.2 pyridine ChenOl: For pyridine [21 and 22], the carbon binding energy is 285.5 eV 21) D. Marton, K.J. Boyd, A.H. Al-bayati, S.S. Todorov and J.W. Rabalais. Phys. Rev. Lett. 73 (1994), p. 118. 22) Mansour and S. Ugolini. Phy. Rev. B 47 (1993), p. 10201. 2.1.3 polyacronitrile polyacronitrile (C Is binding energy: 286.4 eV and N Is binding energy: 399.6 eV) [ChengOl] 5 a.& iiaiiuiuut:» 2.2.1 Lai03 1) The crystalline properties of carbon nitride nanotubes synthesized by electron cyclotron resonance plasma, Thin Solid Films, Volume 444, Issues 1-2, 1 November 2003, Pages 38-43 S. H. Lai, Y. L. Chen, L. H. Chan, Y. M. Pan, X. W. Liu and H. C. Shih =i papers3/nanotubes/cn_nanotubes/lai03.pdf FTIR - The absorption band between 1250 and 1750 cm-1 shows strong evidence for the incorporation of nitrogen into the carbon network,which induced the FTIR active G and D bands [15] .This very broad absorption band is resulted from the superimposition of the NH and CH bending vibrations [16] .The absorption features at 2256 cm and 2926 cm are corresponding to C=N stretching vibrations and CH stretching vibra- tions,respectively.The band at 3451 cm corresponds y 1 to OH in adsorbed H20 from atmosphere on the surface dark layer and the peak is substantially reduced after polishing the surface.A relatively weak absorption peak at 2341 cm-1 was observed after the surface dark layer being removed,as shown in Fig.3b,which is probably due to the C=0 vibration w 17 x resulting from the substitution of oxygen for carbon in the CN-NTs. XPS - The C (Is )line (Fig.5a ) was deconvoluted into two peaks at 287.4 and 286.3 eV,which are consistent with Marton et al. [18] and our previous results [14] .By the theoretical calculations [19] ,the substitution of oxygen atom is minor and does not alter the binding energy and the global structure of the tube,so we do not take the oxygen effect into account.The binding energy of the carbon shifts towards higher position with the binding to nitrogen because of the decreasing electron density on the carbon atoms, which is due to the smaller electronegativity of C (x = 2.5 )than N (chi = 3.0).The free carbon peak at 284.5 eV was neglected because the front dark layer of the composite membrane was polished away.By comparing with urotropine (CeHi2N4,sp3 binding energy:286.9 eV ) [20] and pyridine (CsH5N,sp2 binding energy: 285.5 eV ) [21],the carbon peak at 287.4 eV and 286.3 eV are assigned to be sp3 and sp2 bonding,respectively. N (Is )line (Fig.5b )was deconvoluted into two peaks at 401.7 and 400.3 eV in accordance with Marton et al. [18] and our previous results [15]. By using the same analogy for the carbon peaks,the nitrogen peaks at 401.7 eV and 400.3 eV are assumed to represent the sp2 and sp3 bondings,respectively.Casanovas et al. reported that highly coordinated N atoms replace C atoms in the graphene sheets (401 -403 eV )and pyri- dinic N (399 eV )w 22 x .The ratios of N y C are 0.78 and References: w 17 x A.Heilmann,P.Jutzi,A.Klipp,U.Kreibig,R.Neuendorf,T. Sawitowski,G.Schmid,Adv.Mater.10 (1998 )398. w 18 x D.Marton,K.J.Boyd,A.H.Al-Bayati,S.S.Todorov,J.W. Rabalais,Phys.Rev.B 73 (1994 )118. w 19 x G.Zhang,W.Duan,G.Zhou,B.Gu,Solid Commun.122 (2002 )121. w 20 x M.Barber,J.A.Connor,M.F.Guest,I.H.Hillier,M.Schwi M.Stacey,J.Chem.Soc.Faraday Trans.II 69 (1973 )551. w 21 x U.Gelius,R.F.Heden,J.Hedman,B.J.Lindberg,R.Manne, R.Nordberg,R.Nordling,K.Siegbahn,Phys.Scr.(1970) 70. w 22 x J.Casanovas,J.M.Ricart,J.Rubio,F.Illas,J.M.Jimenez-Mateos,J.Am.Chem.Soc.ll8 (1996 )8071. w 23 x F.Tuinstra,J.L.Koenig,J.Chem.Phys.53 (1970 )1126. w 24 x R.J.Nemanich,S.A.Solin,Phys.Rev.B 20 (1979 )392. 2.2.2 ChenOl The characterization of amorphous carbon nitride films grown by RFCVD method, Journal of Non-Crystalline Solids, Volume 283, Issues 1-3, May 2001, Pages 95-100 Sheng-Yuan Chen and Juh-Tzeng Lue XPS - As shown in Fig. 3(a), the carbon Is line was decomposed into three components occurring at 284.6, 285.5 and 288.3 eV. The 284.6 eV peak corresponds to the existence of nano-crystalline graphite [14 and 20]. The results of Raman spectra also reveal the graphite-phase at 1580 cm-1. In general, the XPS spectra of -C3N4 are compared with pyridine C5H5N and urotropine C6H12N4. For pyridine [21 and 22], the carbon binding energy at 285.5 eV has the same value as the C Is signal occurring in this experiment. For urotropine [21 and 22], the C Is binding energy is 286.9 eV and N Is is 399.4 eV. The trigonal structure of -C3N4 has a higher binding energy of CN bonds rather than the tetrahedral urotropine. In these measured XPS spectra, the C Is at 288.3 eV and N Is at 398.5 eV are referred to the structure of urotropine. The peaks at 285.5 and 288.9 eV thus indicate two different binding states for carbon with nitrogen (21). The corresponding nitrogen binding energy is at 399.7 and 398.5 eV. The additional peak at 405 eV was identified to be due to N-0 bonds. FTIR - The peak at 2352 cm-1 of the FTIR spectra as shown in Fig. 4 is caused by the absorption of C02 molecules existing in the ambient air. Unfortunately the CN stretching mode occurring at 2200 cm-1 is not seen for the low concentration of the nitrogen doping below 9%. The intensity of lines near 1570 cm-1 for the sp2 bonds becomes active with increasing the NH40H concentration. Carbon-carbon stretching vibrations in aromatic groups near 1550 cm-1 become IR active due to the addition of nitrogen at neighboring sites, lne absorption peaks instead or tne transmission dips were tested tor tne uppermost curve. Fig. 5 shows the Raman spectra of a-CN:H compared with a-C:H. Both are decomposed into graphitic G at 1575 cm-1 and disorder D band at 1360 cm-1 as shown in Fig. 5, respectively. The symmetric E2g Raman- active G band for graphite is broken dramatically as the NH40H partial pressure increases (19). The intensity ratio ID/IG increases as the incorporated nitrogen content increases. It is accompanied by a slight reduction of the FWHM of G band from 132-117 cm-1. These results show that the increase of the nitrogen content in a-C:H films induces an increase of sp2 fraction and the grain size of graphite microcrystallines in the films [30 and 31]. References: (21) D. Marton, K.J. Boyd, A.H. Al-bayati, S.S. Todorov and J.W. Rabalais. Phys. Rev. Lett. 73 (1994), p. 118. (22) Mansour and S. Ugolini. Phy. Rev. B 47 (1993), p. 10201. 2.2.3 HammerOl CNX films The binding energies found are 398.3 eV (Al), 400.4 eV (A2) and a small peak at 402.4 eV (A3). The width (FWHM) of all subpeaks is 1.9 eV. It is generally accepted that the A2 component is due to substitutional N in extended graphitic structures, (my comment: C=N, according to Marton94) Theoretical calculations suggest that with increasing size of these clusters the binding energy (EB) shifts to higher values ( 401 eV) (12). The FWHM is determined by their size-distribution. This graphitization effect was detected for samples grown at elevated temperatures (^350C) [13 and 14]. The most contradictory peak assignment in the literature refers to the component Al. Most authors attribute this peak to N atoms bonded to sp3 hybridized carbon [4, 8, 12, 15 and 16], while others identify Al exclusively, due to pyridine like structures at the edges of graphitic clusters [17, 18 and 19] or as caused by nitrile (CN) groups [20]. None of these suggestions is very satisfactory to explain our spectra. In the first case one has to assume for N rich samples a high fraction of sp3 carbon or a preferential bonding of N with sp3 C, both situations are not very probable. The second assignment would indicate an entirely aromatic nature of the material. In the later case, Snis et al. concluded from the comparison of the Raman activity with graphitic modes that the contribution of the CN groups, observed as a small peak at 2200 cm-1, has only a minor effect on the XPS spectra [17]. We propose a multi-structural nature of Al and assign as the main contribution to non-aromatic CN bonds with N having an sp3 hybridization character similar to that in the NH3 molecule. Furthermore, also N bonded to sp3 C (NC3) and for N rich samples nitrile as well as aliphatic groups (NC2) contribute to Al. Only a small effect on the spectra is expected from the pyridine structure (aromatic NC2) with a calculated position at 399.2 eV (12). Finally, the small A3 component at 402.4 eV results from trapped N2 molecules in the film [3 and 12]. The commonly used identification of A3 as due to N-0 groups can be excluded in our in situ XPS diagnosis. The deconvoluted C Is core-level spectra, shown in Fig. 3, include the spectrum of a a-C film grown without nitrogen ion beam assistance. The C Is peak position of the a-C film located at 284.3 eV is identified as due to graphitic structures [15]. Most authors attribute the minor component at 285.3 eV to sp3 carbon [15 and 21]. The inclusion of an increasing amount of N causes a systematical widening and shifting of the C Is spectrum to higher binding energies. This effect is caused by the formation of a variety of different CN binding environments, contributing to the high energy side of the spectrum and the reduced number of pure graphitic sites at 284.3 eV (Bl). Three new components can be fitted at 285.2 eV (B2), 286.2 eV (B3) and 287.4 eV (B4), all with a FWHM=1.6 eV. According to Hammer et al. [3], the components can be assigned to the following structures: the B2 peak is attributed to the aromatic C3N configurations, B3 is assigned to the non-aromatic C3N phase, including sp3 C bonded to N (C4N) and B4 represents the non-aromatic C2N2 configuration. From Fig. 3 it can be easily seen that the intensity ratio of non-aromatic to aromatic structures, (B3+B4)/(B2), increases with the addition of N. Similar behavior of the ratio A1/A2 can be observed in the Nls spectra ( Fig. 2). and much more for CNX:H in the paper!! 2.2.4 Ref. 17 in HammerOl - sehnat! 17. A. Snis, S.F. Matar, O. Plashkevych and H. Agren J. Chem. Phys. Ill (1999), p. 9678 Core ionization energies of carbon-nitrogen molecules and solids A. Snis and S. F. Matar Institut de Chimie de la Matiere Condense de Bordeaux, CNRS, 87, Avenue du Dr. Albert Schweitzer, 33608 Pessac, France O. Plashkevych and H. Agren Department of Theoretical Chemistry, Royal Institute of Technology, S-100 44, Stockholm, Sweden (Received 27 April 1999; accepted 9 September 1999) Core ionization energies have been calculated for various carbon- nitrogen molecules and solids. The systems investigated contain many of the bonding possibilities which presumably arise in carbon nitride tirm nlms prepared under varying conditions, lne molecular core ionization energies are calculated by the SCF self-consistent field method. Several singly, doubly, and triply bonded CxNyHz species have been considered. Core ionization energies of two C11N4 C sp2 and C sp3solids have been calculated with the full-potential linearized augmented plane wave method. Molecular C Is binding energies increase with approximately 1 eV for each singly or doubly bonded nitrogen atom attached. The trend is similar in the solids although variations and saturation effects are obtained due to hybridization and nitrogen content. The Is binding energies of two-coordinated nitrogen atoms in C sp2 molecules and of pyramidal three-coordinated nitrogen atoms in C sp3 molecules are close to each other. The differences depend on the size of the systems and the number of CH3 groups attached. In the solid state compounds, where no CH3 groups are present, the energies of two-coordinated nitrogen in a C sp2 environment are always lower than the energy of pyramidal three- coordinated nitrogen in the C sp3 solid, by more than 1 eV. Concerning the micro structure in thin CNx films, comparisons of the computational results with experiment indicate that at low nitrogen concentrations the atomic configuration close to the N atoms are mostly of sp3 character. At higher N contents more two-coordinated nitrogen atoms are incorporated. The N Is binding energy shifts observed at high substrate temperatures could be explained by either a gradual formation of three-coordinated N atoms in a graphitic-like C sp2 environment or by local domains containing high N concentrations. (c)1999 American Institute of Physics. 2.2.5 Marton94 - only as a printed paper Carbon Nitride Deposited Using Energetic Species: A Two-Phase System D. Marton, K. J. Boyd, A. H. Al-Bayati, S. S. Todorov, and J. W. Rabalais Department of Chemistry, University of Houston, Houston, Texas 77204-5641 Phys. Rev. Lett. 73, 118-121 (1994) Carbon nitride films deposited by three different methods have been analyzed using in situ Auger electron spectroscopy and ex situ x-ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectrometry. The XPS data for all 27 samples indicate that these films have a similar composition consisting of two phases. One phase has a stoichiometry near C3N4 and is identified as a tetrahedral component. The other phase has a variable stoichiometry from C5N to C2N and is identified as predominantly an sp2 bonded structure. For a film composition of [N]/[C] i 1, the tetrahedrally bonded component grows only moderately as the nitrogen content of the films is increased. (c)1994 The American Physical Society URL: http://link.aps.org/abstract/PRL/v73/pll8 2.3 FTIR and XPS 2.3.1 Mutsukura99, TSF, cn/mutsukura99.pdf CNX films obtained (PECVD CH4/N2) were polymer-like transparent soft films. The IR spectra indicate five absorption bands at 3200-3500 cm"1, 2800-3000 cm"1, 2100-2250 cm"1, 1500-1800 cm"1 and 1300-1500 cm-1 regions. The 3200-3500 cm-1 band is composed from three absorption peaks at 3200, 3300 and 3450 cm-1 which were decided by the Gaussian fitting and were consistent with the reported [2] and predicted values [13]. They are identified with N-H stretching vibration, and are associated with both ^NH and NH2 components. The 1500-1800 cm-1 band is predicted to contain some absorption modes such as double bonded C=C and C=N stretching and N-H bending modes. The absorption band at 2800-3000 cm-1 is identified with C-H stretching vibration, which is normally observed in diamond-like carbon films [14]. The absorption band at 1300-1500 cm-1 region has been reported to be related with C-H [2] and C-N [12] bonds. As to the absorption band at 2100-2250 cm-1, the contribution of C=N triple bond has been reported until now [2,3,5-12]. In these previous reports a broad absorption band having single absorption peak has been observed for almost all of the carbon nitride films, except the samples reported by Kaufman et al. [5] which indicated two absorption peaks at 2130 and 2200 cm-1. However, for our samples the band contains obviously several components: 2105, 2160, 2190, 2215 and 2245 cm-1. The vibration frequencies of the C=N stretching modes associated with both nitrile (-C=N) and isonitrile (-N=C) structures, greatly depend on a type of component bonded to these structures. Those appear at 2245-2255 cm"1 and 2226-2229 cm"1 for the nitrile, and at 2146-2183 cm"1 and 2122-2125 cm"1 for isonitrile, when they are bonded to hydrocarbons and aromatic rings, respectively. Table 2.2: Bonding energies bond energy [kcal/mol C-N 69.7 C=N 147 C=N 207 2.3.2 JelínekOO, TSF XPS analyses The Nls spectral lines displayed in Fig. were found to be broad (2.8 eV) suggesting more bonding states of nitrogen atoms. Reasonable fits were obtained with three Gaussian functions 1.5 eV wide (FWHM) peaked at 398.8±0.1 (sp3C-N), 399.9±0.2 (N-H) and 400.9±0.2 eV (sp2C-N). FTIR spectra Nitrile, isonitrile and carbodiimide are assumed to play imporatnt role in of the bridges between aromatic Table 2.3: FTIR identification wavenumber [cm-1] bonds 1600-1630 C=C, C=N, N-H, O-H 3300 N-H, O-H 2220-2230 cm-1 -C=N nitrile 2115-2175 cm-1 -N=C isonitrile 2105-2155 cm-1 -N=C=N- carbodiimide carbon clusters [33,37]. Position of isonitrile does not agree with Mutsukura99 above Chapter 3 Si-related compound 3.1 Analysis of silicones, chapter 10 (FTIR), D. R. Anderson 3.1.1 Si-H • Si-H stretching vibration is one of the most characteristic infrared frequencies for organosihcon materials. It gives a strong band in the 2100 to 2300 cm-1 region where there is very little interference from other bands. It has been shown that the position of the Si-H stretching frequency is dependent on the inductive power of the other groups on the silicon atom, the more electron-withdrawing groups causing shifts to higher frequencies [57]. The position of the Si-H streching band for a particular compound can be predicted from a table of constants characteristic of each substituent [?] group E [cm"1] group E [cm"1] F- 760.8* Me2N- 715.5* Cl- 752.8 CH2 =CH- 709.2 MeO- 734.4* CH3- 705.9 EtO- 732.0* Et- 699.1 H- 724.8 Me3SiCH2- 687.6 HO- 718.6* Me3Si- 684.8 11 Chapter 4 Si-nitrides, carbides and carbonitrides 4.1 About effort in Si-C-N compounds 4.1.1 si-based_hard/sicn/Smirnova03 [?] Silicon carbonitride thin films are attractive since they are expected to combine the properties of silicon nitride and the hypothetical carbon nitride. These films would be resistant to high temperatures and corrosive environments. They may be used as variable band gap materials, dielectric layers, diffusion barriers in semiconductor technology and the materials having unique tribological behaviour.Ternary Si -C -N compounds were commonly deposited using CVD techniques at elevated temperatures [1-3]. Low-temperature deposition processes are preferred for practical application in order to make electronic devices and protective coatings.However, only a few attempts to prepare SiCN alloys have been carried out at low growth temperatures primarily using physical vapour deposition (PVD) methods [4 -10] . In depositing films with CVD process mixtures of CH4, N2, H2 and SiH4 (5% SiH on N dilution) gases in various proportions are widely used as basic reagents [8,11,12] .Such gas mixtures are hazardous. Therefore, the search for novel new volatile precursors to fabricate silicon carbonitride films is required. However,there is no great variety of such volatile substances. Organosilicon compounds could be used as single- source precursors containing silicon, nitrogen, and carbon.Being of no hazard,they are particularly promising for SixCyNzfilm deposition. 4.1.2 si-based_hard/sicn/Peng01 PengOl Silicon carbide nitride material is a covalently cross-bonded ternary system with short-range order, which posses the excellent mechanical, chemical, electrical and optical properties of silicon carbide and silicon nitride [1]. Especially, amorphous silicon carbide nitride thin (r)lms (a-SiCx Ny ) have recently been attracting much attention for its apparent tunability over a wide range from the band gap of SiC (2.86 eV) to insulating film of Si3 N4 (ps 5.0 eV) by controlling the composition, which are of interest in integrated circuits, optical device fabrication and material surface protection [2]. However, only a few efforts have been spent in the recent years to synthesis Si-C-N thin films by reactive sputtering a silicon carbide target in N2+Ar atmosphere [3], nitrogen-ion implantation into SiC [4] (microwave) plasma-assisted or electron cyclotron resonance chemical-vapor-deposition (PACVD, MWCVD or ECR-CVD) using SiH4 -NH3 -CH4 [5,6] or laser ablation of a SiC target in nitrogen atmosphere [7]. Chen et al. [6] reported a SiCx Ny thin film, which contains N 574.4 eV using ECR-CVD. In our data, there is no report on synthesis of SiCx Ny (r)lms by rf reactive sputtering a Si3 N4 target in methane and argon atmosphere. 4.2 FTIR of silicon nitrides 4.2.1 book - Silicon Nitride in Elecronics, V. I. Belyi et al., Elsevier 1988 [?] p. 105 The IR absorption spectrum of partly and completely crystallized silicon nitride reveals the bands typical of the crystalline ct-SÍ3N4 phase: 830-835 cm-1, 870-880 cm-1 (the two strongest bands), 920 cm-1, 1015-1020 cm-1 (weak bands). All the vibrations are valence ones. 13 p. so Valence and deformation vibrations ot all mam oscillators or 013IN4 occur in tne interval or wavelengths entering the IR range (Si-N: 11.6-12.0 /xm, i.e. 862-833 cm-1 - valence [45], N-H: 3.0 /xm, i.e. 3333 cml - valence, 6.4 /xm, i.e. 1563 cm-1 - deformation [46], Si-NH- Si: 8.6 /xm, i.e. 1163 cm-1 - valence [46], Si-H: 4.7 /an, i.e. 2128 cm-1 - valence [46], 8.4 /xm, i.e. 1190 cm-1 - deformation [35]). 4.2.2 si-based_hard/sin/lucovsky83 [?] title: Nitrogen-bonding environments in glow-discharge-deposited a-Si:H films • a-Si:H films - 2000 cml stretching of Si-H, 630 cml bending (or wagging) of Si-H • a-SiN:H films - 2060 cml Si-H, 840 cm-1 in-plane Si-N stretching mode, 3350 cml N-H stretching vibration, 1150 cml N-H bending vibration 4.2.3 si-based_hard/sin/tsu86 [?] title: Silicon nitride and silicon diimide grown by remote plasma enhanced chemical vapor deposition Are the films amourphous? Probably. Films were grown by remote PECVD from mixture of SÍH4 or SÍ2H6 with NH3 or N2/He. We have found that films grown from N2 and deposited at subst. temperature in excess of 350°C have a composition corresponding to stoichiometric SÍ3N4, whereas films deposited from NH3 require subst. temperature in excess of about 500°C to eliminate bonded H and yield the same stoichiometric composition. In contrast films grown from NH3 at temperatures in the range of 50 to 100 circC have a chemical composition corresponding to silicon diimide, Si(NH)2- Films grown from NH3 at intermediate substrate temperatures are solid solutions of SÍ3N4 and Si(NH)2. • SÍ3N4 films deposited from SÍH4+N2: SiH stretching vibration 2180 cm-1 (diminished for T > 350°C), SiN vibration at 835 cm-1, silicon (Si-Si) breathing at about 470 cm-1 • SiNH films deposited from SÍH4+NH3: NH stretching vibration centered at about 3335 cm-1 (medium ir activity), NH bending vibration at 1175 cm-1 (strong ir activity), SiN stretching vibration whose frequency varies between 885 and 835 cm-1, silicon breathing vibration whose frequency varies between 430 and 490 cm-1. In addition the films with high concentration of NH groups display a shoulder on the high frequency side of the 3335 cm-1 band and an additional weak feature at 1545 cm-1. They are interpreted as NH2 stretching vibration and a NH2 scissors bending vibration, respectively. 4.2.4 ftir/lanford78 [?] title: The hydrogen content of plasma-deposited silicon nitride Sensitivity factors for SiH and NH - IR bands, 3350 and 2160 cm-1, are necessary to estimate the concentrations of these groups in the SiN:H films. The factors were obtained from comparison of nuclear resonant reaction analyses (NRRA) that determined H content and IR absorption. Total amount of H atoms/cm2 from NRRA can be compared with area under absorption peak. SÍO2 films deposited for comparison did not exhibit any SiH groups but OH bands, 3645 cm-1 (probably isolated OH) and 3390 cm-1 (probably water). 4.2.5 Materials Science of Carbides, Nitrides and Borides, ed. Y.G. Gogotsi, R.A. Andrievski, NATO Science Series Vol. 68 (p. 96) broad and complex band centered at 3355 cm-1 assigned to Si-NH-Si imido and SÍ-NH2 amido surface groups [28,29] 4.2.6 si-based_hard/sin/lattemann03 [?] • SÍ3N4 films: 875-896 cm-1 asymmetric in plane Si-N stretaching vibration mode [7]. It is well known that the oxygen incorporation in silicon nitride causes a shift in the absorption band due to Si-N bond stretching near 880 cm towards higher wavenumbers.The large value of the full width at half maxima (FWHM )of this band is consistent with the previously reported data [7,17] and refers to the amorphous nature of SÍ3N4_X films.The small peak absorption band observed at 490 cm-1 corresponds to Si-N breathing mode [17] .It can be noted that the samples do not have a characteristic absorption band at 1U4U cm " ot tne asymmetric stretcn mode ot tne bi-U-bi bond.This proves that there is no significant amount of silicon dioxide in the samples. 7. G. Parsons, J.H. Souk and J. Batey. J. Appl. Phys. 70 (1991), pp. 1553- 1560. 17. T. Serikawaand A. Okamoto. J. Electrochem. Soc. 131 12 (1984), pp. 2928-2933. 4.2.7 si-based_hard/sin/parson91 [?] title: There is a large amount of literature dealing with the vibrational frequencies associated with Si-H, N-H and Si-N bonding groups. The assignments for these modes in PECVD silicon nitride are given in Ref. 5 and are briefly summarized here: ( 1) N-H stretching mode at 3330 cm-1 , (2) Si-H stretching at 2140 cm"1 , (3) N-H2 scissors at 1550 cm"1, (4) N- H and N-H2 bending at 1150 cm"1, (5) Si-N stretching between 870 and 820 cm-1, and (6) the Si-N "breathing" mode between 430 and 490 cm-1. The sharp absorption feature occasionally observed at 1100 cm-1 is related to incomplete subtraction of a Si-0 related feature in the silicon 4.3 FTIR on Si-C-N films 4.3.1 papersl/si-based_hard/sicn/peng01 [?] title: Xiao et al. [3] and Savall et al. [11] pointed that although each of its absorption band could be traced to a certain binary bond, the exact vibration frequency was slightly different owing to the complex chemical bonding surrounding each element. For example, the peak at 460 and 1000 cm-1 [12] can correspond to asymmetric and symmetric stretching vibration of Si-N bond. Several Si-C stretching mode were observed corresponding to wave numbers 610, 800-823 cm-1. A weak C-N bond at 1100 cm-1 [12] can also be fitted in all four spectra. A broaden peak at 1250-1560 cm-1 corresponding to C-N, C=N and C=C bond and an additional weak peak at 2170 cm-1 corresponding to C=N stretching mode can also be observed [4,13]. They fitter broad peak 100-1200 cm'1 by three peaks: 800-822 cml Si-C, 996-1012 cm'1 Si-N and 1102-1112 cm'1 C-N 4.4 FTIR on Cl-related films 4.4.1 ftir/Cl-related/Upadhyay04 [?] The untreated PVC copolymer shows two distinct C-Cl vibrations at 695 cm-1 (S'HH ) and a more intense band at 613 cm-1 (S HH) [23 -25 ].Where, the S 'HH and S HH bands are,respectively,due to out-of-plane and in-plane C-CHC1-C skeletal modes trans to neighbouring hydrogen atom. [papersl/ftir/Cl-related/Robinson95]: The Si-H vibrational frequencies for a series of chlorine-substituted silanes are 2118, 2168, 2213, and 2274 cm"1 , for (CH3)3Si-H, (CH3)2ClSi-H, (CH3)Cl2Si-H, Cl3Si-H, respectively [34]. Chapter 5 Organosiloxanes 5.1 Overview about papers • VanOoij97-HMDS04 Deposition from HMDSO (usually) in dc discharge on metal and plastic substrates. — film characterisation: weighting and calculation of thickness, i.e. deposition rate, expecting the density of 1.5 g/cm3; FTIR using the reflection-absorption mode (RAIR) with Spectratech variable-angle specular reflection attachment (IR is well discussed!) • Alexander96-HMDS07 Deposition from HMDSO and HMDSO/02 mixtures (Qhmdso = 20 seem, <3o2 =0-200sccm) in microwave discharge on Al substrates. — film characterisation: XPS (good described together with calibration and peak positions!) • Alexander97a-HMDSO10 Deposition from HMDSO/Ar and HMDSO/Ar/02 mixtures in microwave discharge on Al substrates. — application: corrosion protection — plasma diagnostics: mass spectroscopy of exhaust gases; utilization of parameters from Wagner's and Yasuda's work — film characterisation: IR absorption; XPS; water contact angle; resistivity agains corrosion • Tien72-HMDSOH Deposition from HMDSO/Ar feed (0.3/0.1 Torr) in rf discharge on glass substrates. — application: in integrated optics, i.e. as a waveguide. — film charact.: refractive index, light scattering, electron micrographs • HMDS014 model for polymerization of HMDSO, TENTO CLANEK CHYBIÜ • Lamendola97-HMDS016 Deposition from HMDSO and HMDSO/02 feeds (02/HMDSO= 0-20, p = 50-100 mTorr) in rf parallel plate discharge (2.0 and 4.0 W/cm2) on Si substrates placed on third floating electrode. — application: list of references — plasma diagnostics: OES, actinometry — film charact.: XPS, FTIR, weighting — conclusions: explanation of deposition mechanismus for "high fragmentation" conditions (oxygen added into the feed) • Alexander97b-HMDS017 — film characterisation: XPS only shortly • Aumaille00-HMDSO19 Deposition from HMDSO/02 and TEOS/02 feeds (fixed total flow rate at 16 seem —> change of monomer fraction) in helicon diffusion discharge on silicon? substrates. — plasma diagnostics: OES, actinometry 17 — mm characterisation: spectroscopic ellipsometry; Aťb; gravimetry and A-ray reflectivity; chemical etching using p-etch • Ito-HMDSO20 Deposition from HMDSO and TEOS with or without Ar and 02 in ac and rf discharges (parallel plate). — film charact.: refractive index, dep. rate, XPS, contact angle — chybi citace a nenašla jsem ji ani INSPECem od r. 1996! 5.2 Results on plasma deposition from HMDSO 5.2.1 VanOoij97-HMDS04 [?] Films are divided into two groups: • low power/high pressure (LW/HP) - There are better resolved peaks. A substantial amount of SÍ-CH3 functionality seems to be retained and polymerization occurs partially in the chain-like structure. • high power/low pressure (HW/LP) - Does not seem to be well defined. No long chains can be detected. There are fewer CH3 groups and broader absorption bands indication a higher amount of crosslinking. It also displays a higher relative intensity of Si-H groups, which we interpret to be indicative of a higher monomer breakdown. The XPS (no details presented) shows that the elemental composition of both the LW/HP and HW/LP films were approximately the same and also very close to that of pure PDMS (polydimethylsiloxane) indicating that the differences observed in FTIR spectra were the results of structural differences between the films. The TOF-SIMS results indicated that the LW/HP films had a structure which resembled that of the HMDSO monomer moce closely that that of the HW/LP films. 5.2.2 Alexander96-HMDS07 [?] Table 5.1: Results from XPS analyses in HMDS07. HMDSO flow rate of 20 seem Qo2 C 0 Si C/O C/Si O/Si 0 50.31 22.89 26.80 2.12 1.88 0.85 10 39.93 32.33 27.74 1.24 1.44 1.17 20 35.57 35.56 28.88 1.00 1.23 1.23 40 29.94 41.43 28.63 0.72 1.05 1.45 100 22.66 47.57 29.77 0.48 0.76 1.60 200 18.74 50.76 30.50 0.37 0.61 1.66 HMDSO 66.67 11.11 22.22 6.0 3.0 0.5 5.2.3 Alexander97a-HMDSO10 [?] From IR spectroscopy of films it could be supposed that a higher amount of O2 is forcing demethylation of the films, changing bonds in the polymer from -H to -0-. A possible reason for these effects is a change in the neutral gas phase chemistry.lt is known that the addition of O2 to a reactive mixture of hydrocarbon fragments and H and H2 can lead to high losses of methyl radicals because of the influence of O and OH radicals [HMDS010-13]. Simultaneously, the amount of atomic hydrogen will be reduced due to the production of water via OH radicals. If one adds small amounts of O2 to a H2/Ar plasma, an increase in atomic hydrogen and thus of hydrocarbon radicals may occur [HMDSO10-14]. This situation, however, is fas from our plasma conditions. Looking at the results from the mass spectrometry, no change in the amount of CH4 in the gas phase, but an intensive H2 and CO2 production, was detected. It can be concluded from these circumstances that under certain conditions, H atoms tend to recombine among each other rather than to form CxHyOz. The relative proportion of the atoms at the polymer surface was found by XPS to be 0/C/Si«2.7/3/1 for pure HMDSO/Ar plasma and «2.7/0.3/1 for an additional oxygen admixture. HMDSO monomer has this ratio 0.5/3/1. It means that Si-O-Si cross-links prevail in films, which are grown in presence of additional oxygen. o.z.4 íiemz-niviuavjíi [:j A typical HMDSO film has a refractive index of 1.4880 at 632.8 nm (red He- Ne laser), 1.4960 at 514.5 nm (green argon laser) and 1.4996 at 488 nm (blue argon laser). 5.2.5 chybi!-HMDS014 [?] A simple model was deduced to describe the incorporation behavior of plasma polymerized films in terms of discharge power. The model was based on the dissociation of the chemical bonds of the monomer by inelastic collision with electrons in the plasma. The incorporation rate of the chemical bonds was given as a function of the discharge power under the assumption of the proportionality between the incorporation rate and the concentration of bonds in the plasma. The validity of the model was examined by measuring the relative incorporation rate of Si-O-Si and Si- CH3 bonds in the films deposited by PECVD from HMDSO. The incorporation rate of Si-O-Si bonds decreased with increasing discharge power. There exist a linear relationship between the reciprocal of the incorporation rate and the discharge power, which agrees well with the prediction of the model deduced for one dissociation process of Si-O-Si bond in HMDSO. 5.2.6 Aumaille00-HMDSO19 [?] The influence of the organosilicon fraction (Aľorg = 5-100%) on the deposition rate and the refractive index of the deposited films at 1.96 eV (i.e. 633 nm) is reported. It is clear that simple law between the deposition rate and the organosilicon fraction does not exist. At low values of Xmg, low deposition rates of about 6-10 nm/min are obtained for both organosili-cons. Upon adding the organosilicon precursor to oxygen, the deposition rate increases and saturates at 25 nm/min for the films deposited in pure TEOS plasmas and 50 nm/miin for the films deposited in pure HMDSO plasmas. Thus, at high values of Xorg, the deposition rate is around two times large in HMDSO-derived films that in TEOS-derived films. This result is in agreement with what was found by Latreche [HMDS019_22(PhD thesis)] and Sawada [?]. Ellipsometry in-situ =>• If there are any voids they can be treated in Bruggeman effective medium aproximation (BEMA) as vacuum and not water vapours! At a low Aľorg, the films are transparent in the 1.5-5 eV range, and their refractive index at 1.96 eV is very close to the one of a thermal oxide (n=1.46). The decrease of the refractive index as Xorg is increased, indicates the presence of defects such as microporosity. The BEMA has been used to evaluate the fraction of voids, assuiming that the films is a homogeneous mixture of amorphous SÍO2 and voids [?]. The value of void fraction increase with Xorg reaching 6% for the films deposited in 20%TEOS/80%O2 plasmas, against 2% for the films elaborated by 20%HMDSO/80%O2 plasmas. As Aľorg is above 30%, both the extinction coefficient and refractive index increase. For Xorg =100%, the HMDSO-derived films are more absorbent in the UV (fc(240nm) = 0.052) than TEOS-derived films (fc(240nm) = 0.028). Moreover, at high values of Xmg the organic films derived from HMDSO have a refractive index higher (n(633nm) m 1.535) that the organic films derived from TEOS (n(633nm) ps 1.45). For Xorg <33%, the two elements detected are silicon and oxygen. Carbon is bellow detection limit of XPS analyses. Whatever the organosilicon, the O/Si content is close to two. ... discussion about position of Si 2p and O Is peaks. By increasing the organosilicon fraction, the carbon content in the films increases very rapidly, whereas the oxygen and silicon contents decrease (Table 5.2). Table 5.2: Results from XPS analyses in HMDS019. Total flow rate of 16 seem XOIg =10% XOIg =100% _________TEOS HMDSO TEOS HMDSO 0(%) 67 68 34 34 Si(%) 33 32 13 24 C(%) 0 0 53 42 5.2.7 Ito-HMDSO20 [?] With increasing input power, the refractive index increases monotonously (for pure monomer?). In case of HMDSO n600 = 1.39 for 20 W and n600 = 1.43 for 200 W. However, the composition found by XPS does not cnange. inerelore tney suppose tnat tne increase is caused by increased density. Table 5.3: Results from XPS analyses in HMDSO20. Pure monomer? _________TEOS HMDSO 0(%) 53 27 Si(%) 37 32 C(%) 10 41 Decrease of refractive index with oxygen flow, for HMDSO from 1.42 (pure) to 1.39 (50sccm O2). O/Si from 0.7 to 1.25 (40 seem 02). C/Si from 1.5 to 1.2. Lower oxygen content in the SiOx films results on higher refractive index [?]. Or higher carbon content increase the refractive index [?]. 5.2.8 P0II93-HMDSO2I [?] Exhaust gas spectrometry in the closed reactor and pure HMDSO =^ according to the residence time in the reactor the stable gaseous products can be divided into four groups: • mainly monomer (up to « 20 s) • mainly oligomers (20-110 s) • mainly Si(CH3)x (110-200 s) • mainly CxHy and H2 (200-310 s) Compared with a flow reactor, our reactor is characterised by a high ration of buffer volume to active plasma region (about 100:1). The gas exchange plasma-buffer expands the time scale by diffusion and causes a decrease in deposition rate on the the discharge electrode. In the first stage A (up to 180 s), the production of film-forming species from HMDSO leads to an increasing deposition rate, in spite of the decreasing HMDSO concentration. After consumption of the HMDSO and the stable silicon-containing reaction products the rate decreases (second and third stages, B and C) and reaches zero (at the end of C). Refractive index increases along the transition from stage A to C. Beginning of deposition: 1.44, end of stage A: 1.49. Center of stage B: 1.52. 5.2.9 Lamendola97-HMDS016 [?] Given trend of composition of Si, O and C for various O2/HMDSO ratios (podle pravitka to přepsat!). 5.2.10 Vallee97 [?] Refractive index for HMDSO and TEOS and various discharges (40 kHz, Helicon, DECR) as function of monomer percentage in HMDSO/O2 mixture. For pure HMDSO n = 1.51 for 40 kHz (density 1.25 g/cm3) and n = 1.59 for DECR (density 1.35 g/cm3). For pure HMDSO, DECR the IR spectrum is shown. 5.3 Application of HMDSO films • HMDSOll application of HMDSO plasma polymerized films in integrated optics, i. e. as a waveguide. The films were deposited on the glass substrate. To serve as a light quide, the films must have a refractive index larger than that of the substrate. • HMDS013 application of PP-HMDSO as corrosion protective coatings on metal substrates including carbon steel, stainless steel, Monel etc. Deposition in microwave large scale reactor (2.45 GHz). Resistance to simulated sea water (4% NaCl) was evaluated. • HMDS09 Preparation of metal-organic films by co-deposition of metal with HMDSO (dc discharge) . Chapter 6 Organosilazanes 6.1 Overview of FTIR and XPS on HMDSN 6.1.1 SeekampOO (paper3/hmdsn) FTIR - There are six bands of similar amplitudes which give an insight into the bonding and growth processes for both materials. There is no band from Si-C and Si-N bonds in ceramic environments between 800 and 1000 cm-1 . The first two peaks at 790 and 840 cm-1 can be assigned to Si-(CH3)2 stretching vibrations and Si-(CH3)3 rocking vibrations respectively [6]. The Si-(CH3)2 absorption has a larger amplitude in samples made from HMDS while the Si-(CH3)3 absorption is of equal amplitude in both materials. This similarity means that there are more silicon atoms bound to species other than methyl with two of their bonds in samples made from HMDS compared to samples made from HMDSN. The Si-CH3 deformation band at 1260 cm-1 [6] gives an indication of how many methyl groups there are in the samples. Hence there are more methyl groups bound to silicon in the sample made from HMDSN than in the sample made from HMDS. As there is no absorption for Si-CH3 stretching vibrations at 775 cm-1 [6] detectable in samples from HMDSN and only a shoulder in material from HMDS, the excess methylgroups must be bound in Si-(CH3)4 configurations. The absorption of tetramethylsilane at 695 cm-1 [6] indicates the presence of this substance in the material but it is too small to be quantified. The absorption of in Si-CH2-Si at 1240 cm-1 [6] has more than twice the amplitude for samples made from HMDS than for those made from HMDSN. A band at 1240 cm-1 is often interpreted as a Si-O-Si stretching vibration. For the materials discussed here such an assignment is not valid because of the absence of an Si-O-Si band around 430 cm-1 [6] that is always observed for oxidised films deposited under con- ditions discussed here [7,Seekamp98]. Two of the bands, the asymmetric Si-N-Si stretching vibration at 923 cm-1 [6] and the Si-NH-Si bending band at 1184 cm-1 , only appear in the spectra for material de- posited from HMDSN. Both these bands have almost the same amplitude in the spectrum of liquid HMDSN. Their relative amplitudes in the sample spectrum is similar to that found in the spectrum of liquid heptamethyldisilazane [9]. Hence the concentration of N-CH3 bonds for the deposited material increased compared to the liquid starting material and the N-H bond is not fully preserved. 6.1.2 Baraton98 (paper3/hmdsn) 3320 cm-1 adsorbed water, 3780-3600 cm-1 !/(OH) stretching mode of different types of hydroxyl groups bonded to Ti atoms. The remaining bound water molecules are indicated by the broad band at 3480 cm-1 assigned to z/(OH) stretching mode in perturbed hydroxyl groups and by the band at 1620 cm-1 assigned to (5(OH) bending mode in water molecules. Bands centered at 2348 cm-1 assigned to CO2, 1352 cm-1 to (5(CH3) bending mode. 6.1.3 Pecheur99 (paper3/hmdsn) SiO-H absorption at 3635 and 936 cm-1, Si-H in O2SÍ-H in the interval 2213-2236 cm-1. Around 2966 cm-1 C- H3 [13]. Two smaller bands between 1420-1350 cm-1 attributed to the deformation of SiC-H bond [14]. Moreover, IR spectra show an arear between 3390 to 3500 corresponding to N-H and N-H2 vibration mode [15] and at 888 cm"1 to Si-NO. 13. J.H. Lee, Y.H. Lee and B. Farouk. J. Vac. Sei. Technol. A 14 5 (1996), lp. 2702. 4. M. Latreche, PhD thesis, Universit Paul Sabatier, Toulouse, lFrance, 1993 5. A. Sassela, A. Borghesi, F. Corni, A. Monelli, G. Ottaviani, IR. Tonini, B. Pivac, M. Bacchetta, L. Zanotti, J. Vac. Sei. Technol. A 15 (2) 1(1997) 21 !!!! nemam clanek 6.1.4 Fainer03 /papers/hmdsn XPS- It was revealed that all peaks consist of more than one Gaussian peak that indicate multi- pie bonding between the constituent atoms of Si,C and N.The Si 2p photo-electron peak could be resolved into two peaks centred at 100.3 -100.6 and 101.6 -101.8 eV,belonging to Si -C and Si -N bonding,respectively.The C Is photoelectron peak consists of three components centred at 283.1-283.8, 284.5-284.8 and 285.7-286.1 eV, belonging to C-Si,C-C and C-N bonding [4,5].The N Is photoelectron peak consists of one component centred at 397.3-397.6 eV,corresponding to N -Si bonding. Unfortunately,the present level of our understanding of the crystal structure of SiC x N y .1ms is insuf .cient.We can propose that a plausible structure could be that of Si3 N4 in which some of the Si atoms are substituted by C atoms. [4 ]M.T.Kim,J.Lee,Thin Solid Films 303 (1997)173. -bad refference, there is nothing about XPS [5 ]T.Tharigen,G.Lippold,G.V.Riede,et al.,Thin Solid Films 348 (1999)103. 6.1.5 Gengenbach99 /papers3/hmdsn FTIR - XPS - detailed discussion! HMDSN: Some oxygen (O/Si 0.17) was detected in the freshly deposited film which might have been partially due to oxygen impurities in the discharge and/or to exposure to atmosphere. The O Is BE of 532.3 eV, which was somewhat higher than expected for Si-O-Si probably indicated the presence of various oxygen-containing structures such as Si-O-Si, Si-O-C and O-C structures. A low concentration of C-0 bonds was indicated by a weak C Is signal detected at somewhat higher binding energy (about 1 to 2 eV) than the main carbon peak. The chemical changes during storage for ppHMDSA were much more extensive compared to ppH-MDSO. The O/Si ratio increased from 0.17 to about 1.15, accompanied by the almost complete loss of nitrogen, with N/Si decreas-ing from 0.36 to about 0.05, as shown in Fig. 5. A decrease of the C/Si ratio was also observed, from 2.24 to 1.75. The increase in O (DO/Si 0.98) was somewhat higher than the combined loss of N and C (DN/Si 1 DC/Si 20.80). In contrast to the corresponding ppHMDSO data, the O/Si ratio increased significantly during the first day (DO/Si 1 0.08 within the first five hours). This evolution is similar to the oxidative ageing of other plasma polymers, where the amount of oxygen incorporated (DO/C) during the initial, very rapid phase of oxidation was in the range 0.04 to 0.07 [18-20]. This first stage of oxidation after deposition was assigned to the quenching of radicals in the plasma poly-mers by 02 on exposure of the material to air. We therefore propose the same interpretation for the ppHMDSA coating. More specific information was obtained by monitoring the evolution of peak shapes and BEs of the relevant photo-electron signals: Fig. 6 displays the BE values measured for the O Is and Si 2p signals (referenced to C Is at 284.40 eV). Whereas the O Is BE did not change measurably, the Si 2p BE increased by approximately 1 eV to about 102.2 eV. The latter value is indicative of siloxane units. However, the overall Si 2p peak width increased from about 2.4 eV to approximately 2.7 eV during storage whereas in the case of the ppHMDSO coating this value remained unchanged at 2.3 eV. It follows that in the ppHMDSA material siloxane units were present in a variety of structural environments, in contrast to the ppHMDSO film which had a more uniform structure. The N Is signal developed into a doublet. The two components were quantified using the following curvefit protocol: all N Is spectra were fitted with a two component model with the position of the two peaks being uncon-strained. Based on this first round of fitting, the mean peak separation determined was 2.28 eV ± 0.26 eV. All fits were then reoptimised with the separation of the two components fixed at that value. The BEs of the two components did not change during ageing within experimental uncertainty. While the original component at 398.0 eV (Si-N) lost inten-sity rapidly, a new component appeared at about 400.0 eV, increasing slowly in peak height until both peaks eventually displayed approximately the same, albeit weak, intensity (Fig. 5). The latter BE value is typical for aged alkyla-mine- based plasma polymers [19,20] and is characteristic of functional groups where the nitrogen is associated with oxygen on the same C atom, such as amide groups but is too low for oxidized N (nitrites, nitrates). The C Is peak, which initially had been symmetrical, developed a distinct tail at higher BE, evidence for some incorporation of oxygen into hydrocarbon structures. Since the additional C Is components remained rather weak and were not clearly resolved, the newly formed carbon-oxygen-functional groups were quantified by C Is curvefits using established values for the chemical shifts of C Is BE compo-nents relative to aliphatic hydrocarbon at 285.0 eV (11.5 eV for C-O, 12.9 eV for C=0 and 14.3 eV for 0-C=0 based groups) [28]. Thus, fits were calculated based on five components with fixed separations from the main peak (C-Si at 284.4 eV) of 10.6 eV (CHx), 12.1 eV (C-O), 13.5 eV (C=0) and 14.9 eV (0-C=0). For the C-O signal a value of 3.5% ± 1.0% of the total C Is intensity was obtained. This value did not ciiange witnm experimental uncertainty over time. ŕig. t displays tne evolution ot carbonyls/amides and acid/ester groups as a function of storage time. These data, which parallel oxida-tive changes in other plasma polymers [18,19] but are much less extensive, indicate that oxidation of hydrocarbon moieties occurred. [1] Inagaki N, Kishi A. J Polym Sei, Polym Chem Ed 1983;21:2335. [2] Inagaki N, Kondo S, Hirata M, Urushibata H. J Appl Polym Sei 1985;30:3385. [18] Gengenbach TR, Vasic ZR, Chatelier RC, Griesser HJ. J Polym Sei, Part A: Polym Chem 1994;32:1399. [19] Gengenbach TR, Chatelier RC, Griesser HJ. Surf Interf Anal 1996;24:271. [20] Gengenbach TR, Chatelier RC, Griesser HJ. Surf Interf Anal 1996;24:611. [28] Beamson G, Briggs D. High resolution XPS of organic polymers. The Scienta ESCA300 database. 1st ed. Chichester, UK: John Wiley and Sons Ltd, 1992. 6.1.6 Grafting with HMDSN - citation? 2973 and 2914 cm"1 are z/(CH) stretching bands in Si(CH3)3, intense 1267 cm"1 is c5s(CH3), 3736 cm"1 is y(OH) in Si-OH groups 6.1.7 Ungureanu03 (papers3/hmdsn) 3765 cm-1 OH stretching in isolated silanols (Si-OH), 3200-3600 cm-1 OH stretching in hydrogen-bonded silanols, 2975 cm-1 C-H stretching in methyl groups 6.1.8 Tanaka98 Si-(CH3)3 groups are hydrophobic. 6.1.9 Fainer03 (papers/hmdsn) PECVD from HMDSN+NH3, FTIR, XPS, elips, etc. IR-spectra of silicon carbonitride films (HMDSN+He) synthe- sised in the temperature region of 473-773 K consist of the main adsorption band of 600-1200 cm-1,corresponding to the superposition of the Si-C (800 cm_1)and Si-N (900-950 cm-1) stretching modes and the narrow peak at 1250 cm-1 presumably corresponding to the C-N stretching mode [Kim97,Tharigen99]. IR-spectra of the films grown at higher temperatures (773 -1173 K)consist of the wide band of 700 -1100 cm-1.In addition, there is the narrow peak at 620 cm-1 ,correspond- ing to the disorder in SiC x N y .There are no hydrogenous bonds in the spectra.The band of 700 -1200 cm-1 was deconvoluted using Gaussian line shapes into the Si-C (800 cm_1)and Si-N (950 cm_1)bands. As seen from Fig.2a,the rise of the temperature up to 1123 K leads to a monotonie increase of the integral intensity ratio (I /I ) in the IR-spectra. XPS - The chemical compositions of the SiC x N y .1ms determined by XPS are given in Table 2.It was shown that the concentration of oxygen is below 10 at%.The concentration of the main elements changes insignificantly with the synthesis tempera- ture rise.Binding energies of Si 2p,C Is and N Is core levels of this ternary compound are listed in Table 3.It was revealed that all peaks consist of more than one Gaussian peak that indicate multi- pie bonding between the constituent atoms of Si,C and N. The Si 2p photoelectron peak could be resolved into two peaks centred at 100.3-100.6 and 101.6-101.8 eV, belonging to Si-C and Si-N bonding, respectively. The C Is photoelectron peak consists of three components centred at 283.1-283.8, 284.5-284.8 and 285.7-286.1 eV, belonging to C-Si,C-C and C-N bonding [4,5].The N Is photo-electron peak consists of one component centred at 397.3-397.6 eV,corresponding to References: [4] M.T.Kim,J.Lee,Thin Solid Films 303 (1997)173. [5] T.Tharigen,G.Lippold,G.V.Riede,et al.,Thin Solid Films 348 (1999)103. Chapter 7 XPS - summary 7.1 CNX films [Dawei97] In either cubic or ß phase C3N4, each C atom is sp3 hybridized and cr-bonded with four N atoms, forming a tetrahedral configuration. As nitrogen has a greater electronic affinity, the electron cloud of the C-N covalent bond tends to move near the N atom. This transfer of negative charge increases the binding energy of the C(ls) and reduces the binding energy of the N(ls) electron (compared with that of the N2 molecule). In rhombohedral C3N4, each carbon atom is sp2 hybridized and cr-bonded with three nitrogen atoms, making up a hexagonal structure. In the planar network of the hexagonal lattice, each atom, carbon or nitrogen, has a solitary electron, which form the 7r bonding between the interplanar C and N atoms (C=N bonds), making the structure a stable one similar to the benzene structure frequently found in organic compounds. Owing to the presene of C=N bonds, the rhombohedral C3N4 has the greatest chemical bond energy and therefore is chemically most stable among three C3N4 phases. [Dawei97] About 30 papers dealing with CN films and XPS reffer to the urotropine. Some papers (Liu02,Lai03) reffer to Marton94 or accordingly with Marton94 to the comparision with urotropine and pyridine (Zheng96). Then the lowest BE assigned to C-N (sp3), a little bit higher to C=N and the highest to N-N, N-O. Other refferences are Fernandez03 - Ref [29] J.C.Sanchez-Lopez,C.Donnet,F.Lefebvre,C.Fernandez- Ramos,A.Fernandez,J.Appl.Phys.90 (2001 )675. Sanchez-Lopez02 - Ref. [13] W.T. Zheng, H. Sjistrm, I. Ivanov, K.Z. Xing, E. Broitman, W.R. Salaneck, J.E. Greene and J.E. Sundgren. J Vac Sei Technol A 14 (1996), pp. 2696-2701. Ref. [14] J. Wei, P. Hing and Z.Q. Mo. Wear 225/229 (1999), pp. 1141-1147. Review of others in paper BellOl, HammerOl. HammerOl is very good and detailed paper! They consider nitrile only for nitrogen rich samples. ChengOl inform that C=N in IF spectra at 2200 cm-1 is observed in N-rich samples. HMDSO films (numbered): Alexander96 (well described including calibration), Alexander97a, Alexan-der97b (short), AumailleOO HMDSN films: Fainer03, Gengenbach99 (detailed discussion), Tanaka98 7.2 Summary tables My fit of APG films Ols: one peak: 532.9 eV, FWHM 2.2 eV Anyway the BE is too high to be correct. We have to do some corrections and this support the assumption that main carbon peak belongs to C-Si and not to C-C bonds. In the FTIR we can see Si-OH bonds? Do we have also N-0 bonds? • 533.9 =1 (cor. -0.3) 533.6 - Si02 • 532.9 (high) =1 531.7 • 531.5 =;. 530.3 25 Table 7.1: XPS - Cis ref. BE [eV] bonds Song94 (in BellOl) 284 graphite Song94 (in BellOl) 284.8 diamond Gelius70 285.5 pyridine sp2C-N Barber73 286.9 urotropine sp3 C-N Lai03 CNX films 284.5 286.3 287.4 free carbon peak sp2 C=N sp3 C-N Liu02 CNX films 284.4 285.6 287.3 free carbon peak sp2 C=N sp3 C-N Fernandez03 CNX films 284.6 285.9 287.7 pure graphitic sites in a-CNx matrix + C-H contamination CN bonding CN bonding Sanchez-Lopez02 CNX films 284.6 285.9 287.7 free pure carbon + adventitious C sp2 C=N (ÓE = 1.3 eV) sp3 C-N (ÓE = 3.1 eV) BellOl CNX films 284.4 285.1 287.8 pure carbon sp2 C=N (ÔE = 0.7 eV) sp3 C-N (ÔE = 3.4 eV) Marton94 284.6 CNX films 285.9 287.7 289.5 HammerOl 284.3 CNX films 285.2 286.2 287.4 adventitious carbon sp2 C=N (ÔE = 1.3 eV) /3-C3N4 (ÓE = 3.1 eV) CO (ÓE = 4.9 eV) graphitic C aromatic C3N non-aromatic C3N includ. sp3C-N (C4N) non-aromatic C2N2 Chowdhury 286 CNX films diff. approach 288.5 sp2 C= spCE =N :N Riedo-applchem 284.4 pure DLC 285.2 graphite diamond Riedo_applchem 284.7 CNX films 286.2 287.3 288.7 Tharingen99 283.7 SiCN hard films 284.5 285.5 286.8 288.6 intermediate between sp2 and sp3 C=N (ÔE = 1.5 eV) C-N, C=N (ÔE = 2.5 eV) C-0 (ÓE = 4 eV) Si-C C-C, amorphous free carbon C(sp2)-N C(sp3)-N C-0 YuOO SiC films 283.1 284.5 Si-C graphitic C KlepsOl SiC films 282.5 284.6 silicon carbide graphitic C ZajickovaOl 284.8 286.4 288.6 283.0 C-C, C-H C-0 (ÓE = 1.6 eV) C=0 (ÓE = 3.8 eV) C-Si Beamson, Briggs92 284.38 C in CHcj-Si environment Alexander96 Zuri96 Gengenbach99 283.8 C in Si-CH2-Si environment 284.4 C in CH3-Si or Si-(CH2)2-Si environment (in PDMS 0-Si(CH3)2-0) 284.7 C in phenyl carbon (radical from benzen) 285 adventitious hydrocarbon contamination PP-HMDSO films 284.4 283.8 284.4 285 286.5 287.9 289.3 285 9SR ň C-Si C-Si in Si-CH2-Si C-Si in siloxanes CHrma;, i. e.aliphatic hydrocarbons (A C-0 (A = 2.1eV) C=0 (A = 3.5eV) 0-C=0 (A = 4.9eV) C-C C.-Ci MR = 1 K pVÍ 0.6eV) Table 7.2: XPS - Nis ref. BE [eV] bonds Lindberg75 (in Marton94) 399.4 urotropine N-C sp3 Boehland81 (in Marton94) 399.8 * pyridine N-C sp2 aromatic! in BellOl cca 398 C=N (polyacrylonitrile) Lai03 400.3 401.7 N-C sp3 N=C sp2 Liu02 398.3 400.2 N-C sp3 N=C sp2 Fernandez03 398.1 400.2 N-C sp3 (urotropine) N=C sp2 (pyridine) Sanchez-Lopez02 399.1 400.8 402.7 N-C sp3 N=C sp2 N-0 BellOl (no C=N in IR+Raman) !! errors in text 397.6 399.1 401.4 probably /3-C3N4 written N-O, N-N probably C=N written C=N probably N-O, N-N, written /3-C3N4 Marton94 398.3 400 402 /?-C3N4 N=C sp2 N-N, N-0 Hammer01-CNX 398.3 400.4 402.4 N-sp3C3, sp3N-C (non-aromatic) + (for N rich samples) N N-sp2C N2 HammerO 1-azaadenine 398.6 399.3 400.1 400.7 401.2 CNi pyridine (aromatic NC2) N2C (one double bond) -N2C N3 aliph. (& NH2) non-aromatic NC2, NC3 pyridine (aromatic NC2) N2C aliph. N3 aliph. (« NH2) N2 molecule Hammer01-CNX:H 398.7 399.3 400.3 401.2 402.4 other approach Chowdhury99 398.8 400 C=N N-C sp2 Beamson, Briggs92 398.9 400.2 sp3 C-N C=N Gengenbach99 397.48 397.8 398 400.0 i 400 Si3N N-Si, recherche Si-NH-Si, fresh aged alkyl-amine polymers, functional group N- oxidized N (nitrites, nitrates) ref. Table 7.3: XPS - Si2p BE [eV] bonds ZajickovaOl 103 SiC-4 101.4-100.7 SiOxCy 99.9-99.6 Si-Si Fourches93 103.5 SiC-4 102.3 SiOx 101.3 SiOxCy 100.3 SiC GaoOO (SiCN films) 101.7 Si-N, Si-0 Gong99 (SiCN films) 101.5 Si-N 99.2 Si-C, Si-Si Alexander96 103.4 silica SÍO4 102.1 PDMS 0-Si(CH3)2-0 101.8 PP-HMDSO Si(CHx)yHz-0 (y + z = 3) Gengenbach99 100.6±0.38 =Si-Si=, =Si-C= 101.2 N/A =N-Si= recherche 101.2 Si-NH-Si 102.15±0.36 [-Si(CH3)2-0-]„ (siloxane) 103.49±0.13 Si02 (silica), -0-Si(0)-0- Beamson & Briggs 102.40 Si 2pi/2 in PDMS 101.79 Si 2p3/2 in PDMS, main peak 102.29 Si 2p1/2 in PPMS 101.68 Si 2p3/2 in PPMS, main peak Table 7.4: XPS - Ols ref. BE [eV] AumailleOO Gengenbach99 (rech) Beamson & Briggs bonds Alexander96 532.4 Si-O-Si in PPMS, PPDMS 532.6 Si-O-Si in quartz Perkin-Elmer 532.5-533.2 Si02 532.5-533.7 nitrates 530.9-532 hydroxides 530.5-531.5 carbonates 532.7 04Si 532.93±0.34 Si02 (silica) 532.11±0.12 [-Si(CH3)2-0-]„ (siloxane) 532.00 Si-O-Si in PDMS or PPMS 532.64 C-O-C aliphatic in CHO polymers, e. g.C-C-O-C-C 532.89 C-OH aliphatic in CHO polymers 533.15 O-C-0 in CHO polymers, e. g.C-C-O-C-O-C 531.1 C-O-C in PEOx,i.e.C-C-0-C-N2C 531.3-531.9 0=C-N, e. g.polyacrylamide 0=C(CN) /.o iviy lit úl ^vjto uii niviuou aiiu xiiv±.l»oi> .^.jrvjr iiiins Nis: 401.2 - sp3 N bonded to some hydrogen —>• korekce 400.8 400.1 - N-sp2C ->• korekce 399.7 398.6 - N-sp3C ->• korekce 398.2 other possibility FWHM=1.6 fixed 401.5 —>• 401.2 - sp3 N bonded to some hydrogen 400.1 -> 399.8 - N-sp2C 398.8 -> 398.5 - N-sp3C C Is: (varianta c2) FWHM=1.6eV fixed 284.4 - CH3-Si; real position 284.7 ->• correction -0.3 285 - C-C, C-H (ÔE = 0.6 eV); fixed real position 284.7+0.6=285.3 286.4 - C-0 (286.5-286.6, ÔE' = 1.5-1.6 eV)), C=N (286.3, ÔE' = 0.7, 2x1.3, 1.5 eV); free real pos. 286.7 (ÓE = 2.0 eV) 287.7 - sp3C-N (ÔE' = 2.5, 3.1, 3.4 eV); free real pos. 288 (ÔE = 3.3 eV) 288.8 - C=0 (ÓE1 = 2.9, 3.8, 4, 4.9 eV); free real pos. 289.1 (ÔE = 4.4 eV) (varianta ) FWHM=1.6eV fixed 284.4 - CH3-Si; real position 287 ->• correction -2.62 285.8 - C-0 (286.5-286.6, ÔE' = 1.5-1.6 eV)), C=N (286.3, ÔE' = 0.7, 2x1.3, 1.5 eV); contribution of C-C, C-H free real pos. 288.4 (ôE = 1.5 eV) 287.4 - sp3C-N (ÔE' = 2.5, 3.1, 3.4 eV); free real pos. 288 (ÔE = 3.1 eV) 288.9 - C=0 (ÓE1 = 2.9, 3.8, 4, 4.9 eV); free real pos. 289.1 (ÔE = 4.4 eV) (varianta c3) FWHM=1.7eV fixed 284.4 - CH3-Si; real position 284.9 =l poloha 283.2 285 - C-C, C-H (ÔE = 0.6 eV); real position 286.2 (1.3) =l nabijeni -1.2 286.4 - C-0 (286.5-286.6, ÔE' = 1.5-1.6 eV)), C=N (286.3, ÔE' = 0.7, 2x1.3, 1.5 eV); real pos. 287.6 (1.4) =i poloha 286.4 288.1 - sp3C-N (ÔE' = 2.5, 3.1, 3.4 eV); real pos. 288.9 (2.7) =i poloha 287.7 not taken into account 288.8 - C=0 (ÔE' = 2.9, 3.8, 4, 4.9 eV); real pos. 290.1, outside the range! =i 288.9 289.3 - 0-C=0 Si2p: The highest BE is for silica (Si04) at 103.5 eV. 103.5 - silica (Si04) 102.5 - SiOx 101.1 - Si-N Table 7.5: Fits of XPS Nis signal sample peak area position FWHM %Lorentz [eV] [eV] HMDS01 X=12.0 0 401.186 1436.585 1.900 0 1 399.944 5246.289 1.700 0 2 398.642 2393.655 1.500 0 HMDS04 X = 45.6 0 401.068 2761.824 1.900 0 1 399.867 7468.423 1.700 0 2 398.541 3184.302 1.565 0 HMDSN1 X = 45.6 0 400.847 4650.752 1.700 0 1 399.909 12463.39 1.700 0 2 398.787 9291.873 1.700 0 HMDSN2 X=16.7 0 401.134 1187.135 1.700 0 1 399.935 4297.403 1.700 0 2 398.706 2615.157 1.700 0 HMDSN3 X = 40.5 0 401.089 3267.035 1.700 0 1 400.235 8687.732 1.700 0 2 399.159 9779.181 1.700 0 HMDSN4 byt fixni, proc?! X = 88.9 0 400.700 3200.000 1.700 0 1 399.500 6483.166 1.700 0 2 398.198 1579.909 1.700 0 HMDSN5 X=16.4 0 401.312 1628.066 1.700 0 1 399.987 7062.621 1.700 0 2 398.677 3645.203 1.700 0 Chapter 8 Infrared absorption - summary [?]: All the FTIR spectra exhibit a sloping baseline due to an optical interefence effect, which has been removed by fitting the experimental curve in the transparent region. The normalized absorbance spectra were obtained by converting the corrected transmission spectra to absorbance spectra and dividing the result by film thickness (determined using spectroscopic ellipsometry). 8.1 Good papers specific to FTIR Papers with FTIR on HMDSN films: • SeekampOO (paper3/hmdsn) - see text above • Liang03 (papers3/hmdsn) • gonzalez_luna98 (papers3/hmdsn) Deposition of silicon oxinitride films from hexamethyldisilizane (HMDS) by PECVD, Thin Solid Films, Volume 317, Issues 1-2, 1 April 1998, Pages 347-350 R. Gonzlez-Luna, M. T. Rodrigo, C. Jimnez and J. M. Martnez-Duart Papers with FTIR on CSixNy films: • Tharigen99 (papers/sicn) - CSixNy films, XPS, FTIR etc. Table 3. FTIR absorption lines (cm-1) of CSixNy films deposited from graphite targets with 0 Papers with FTIR on CNX films: • JelinekOO (papersl/cn) • Mutsukura 8.2 Summary tables assigment at »sorption band [cm ] C-H asym. str. 2960-2950 C-H sym. str. 2910-2890 Si-H str. in SiHx -CH3 sym. def. in Si(CH3)x 1010-980 -CH2- wagging in SÍ-CH2-SÍ Si-O-Si and/or Si-O-C str. Si-C str 830-800 Si-Si asym str 455 Table 8.1: Infrared Absorption Bands in spectra of TMSS - Wrobel 31 Table 8.2: Infrared Absorption Bands of methylsilyl group - Organometalic Che. Rev. 68., Horak compound -CH3 -CH3 -CH3 -CH3 -CH3 -CH3 vibration ^as(CH3) ľ8(CH3) áas(CH3) 4(CH3) pas(CH3) pas(CH3) wavenumber 2950-2973 2895-2913 1395-1465 1240-1285 800-900 750 ref. Organometal. Chem. Rev. Organometal. Chem. Rev. Organometal. Chem. Rev. Organometal. Chem. Rev. Organometal. Chem. Rev. Organometal. Chem. Rev. -SiCH3 char, for -Si(CH3)x 4(CH3) -« 1250 -Si(CH3)3 4(CH3) 1250 HMDSOl HMDSO 4(CH3) 1252 Organometal. Chem. Rev. 19f area sa 800 decides among RSi i, R2Si and R3Si -Si(CH3)3 pas(CH3) « 850 Organometal. Chem. Rev. 19f HMDSO pas(CH3) 843 Organometal. Chem. Rev. 19f -Si(CH3)3 ps(CH3) « 750 Organometal. Chem. Rev. 19f HMDSO ps(CH3) 756 Organometal. Chem. Rev. 1968, HI -Si(CH3)3 ^as(SiC3) Pa 700 Organometal. Chem. Rev. 19f -Si(CH3)3 ^s(SiC3) 600-660 Organometal. Chem. Rev. 19f -Si(CH3)2 Ps,as(CH3) 800-850 Organometal. Chem. Rev. 19f -Si(CH3)2 P(CH3) 800 HMDS016 -Si(CH3)2 ^as(SiC2) 760-820 Organometal. Chem. Rev. 19f -Si(CH3)2 ^s(SiC2) 650-700 Organometal. Chem. Rev. 19f -Si(CH3) P(CH3) x 800 Organometal. Chem. Rev. 19f -Si(CH3) i/(SiC) ^ 750 Organometal. Chem. Rev. 19f CH3SiH3 CH3SiH3 CH3SiH3 sym. deformation CH3 1266 rocking CH3 870 stretching Si-C 701 Table 8.3: Infrared Absorption Bands in n-alkane - Horak compound vibration wavenumber CH3 asym. stretching 2958-2954 CH2 asym. stretching 2927 CH3 sym. stretching 2872-2869 CH2 sym. stretching 2855-2853 Table 8.4: Infrared Absorption Bands in liquid HMDSO and HMDSN -Organometalic Che. Rev. 68. wavenumber monomer vibration 3385 HMDSN N-H 2962 HMDSN ^as(CH3) 2956 HMDSO ^as(CH3) 2903 HMDSN i/B(CH3) 2899 HMDSO i/B(CH3) 1402 HMDSN,HMDSO • 2150 HMDS019 - yes from 33% Si-H 2300-2100 HMDSOl yes(I) yes (t) no Si-H in Si-Hx 2100 HMDS09 - yes - Si-(CH2)X-Si 1400 HMDS019-15 - yes no Si-(CH2)X-Si 1360 HMDS019-15 - yes no Si-CH3 bending 1270 HMDS016,16-28,16-29 yes yes no Si-CH3 sym. def. 1260-1250 HMDS014,14-18 - yes - Si-(CH3)X 1250 HMDSOl,19-15 - yes no Si-CH3 1250 HMDS09 - yes - Si-O-Si stretch. 1070 HMDS016 yes yes yes Si-O-Si 1090-1020 HMDS01,9 yes yes yes Si-O-C 1090-1020 HMDS01,9,14,14-17 SiO-CH3 1000-1100 HMDS09 - yes - Si-CH2-Si wagging 1090-1020 HMDS014,14-14,14-15 - yes - Si-CH3 rocking 990-980 HMDS014,14-16 - yes- Si-OH bending 930 HMDS016 no no no Si-(CH3)X 890 HMDS019-15 - yes no Si-(CH3)3 rocking 840 HMDS016,16-28,16-29 yes yes Si-(CH3)X 810 HMDS019-15 - yes no Si-(CH3)2 814-800 HMDSOl yes yes yes Si-CH3 stretch. 800 HMDSOl,16,16-28,16-29 yes yes Si-(CH3)2 rocking 800 HMDS016,16-28,16-29 yes yes Si-O-Si bending 800 HMDS016 ? ? yes Si-CH2 800 HMDS09 - yes - Si-(CH3)3 755 HMDSOl yes no no Si-O-Si rocking 450 HMDS016 ? ? yes Si-O-C 500-300 HMDSOl yes yes yes Table 8.7: Infrared Absorption Bands in spectra of HMDSO. Data for Si-(CH3) aging, x =1,2,3 are taken from [5], [6]. Si-OH groups are generally responsible for siloxane film assigment absorption band [cm x SÍ-CH3 deformation 1260 Si-CH2-Si 1240 Si-(CH3)3 rocking 840 Si-(CH3)2 stretching 790 Si-CH3 stretching 775 Si-(CH3)4 695 Si-N-Si asym. stretching 923 Si-NH-Si bending 1184 Si-N 950 broad Si-N 450 ^s(Si3N) 438 ^as(Si3N) 916 CHX 1250 CHX 1300 S-C 800 broad N-Hx, O-H 3400 Si-OH 3738 C=C, C=N, N-H, O-H 1600-1630 N-H, O-H 3300 -C=N nitrile 2220-2230 cm-1 -N=C isonitrile 2115-2175 cm-1 -N=C=N- carbodiimide 2105-2155 cm-1 N-H stretching 3200, 3300, 3450 c= =C, C=N stretching, N-H bending 1500-1800 C-H stretchign 2800-3000 C-H, C-N 1300-1500 C=C 1680 -C=N in alyphatic 2245-2255 -C=N in aromatic 2226-2229 -N=C in alyphatic 2146-2183 -N=C in aromatic 2122-2125 ref. where Seekamp00_6 Seekamp00_6 Seekamp00_6 Seekamp00_6 Seekamp00_6 Seekamp00_6 Seekamp00_6 Seekamp00_6 Liang03_ll Liang03_ll Organomet. Chem. Rev. 1968 Organomet. Chem. Rev. 1968 Liang03 Liang03 Liang03 Liang03 Baraton03 JelinekOO JelinekOO JelinekOO JelinekOO JelinekOO Mutsukura99 Mutsukura99 Mutsukura99 Mutsukura99 Mutsukura99 Mutsukura99 Mutsukura99 Mutsukura99 Mutsukura99 HMDSN+HMDS films HMDSN+HMDS films HMDSN+HMDS films HMDSN+HMDS films HMDS films TMS HMDSN liquid+films, heptaMDSN HMDSN liquid+films, heptaMDSN a-Si3N4 a-Si3N4 (R3Si)3N (R3Si)3N Si3N4 powder Si3N4 powder SiC powder Si3N4 powder CNX films CNX films CNX films CNX films CNX films jNR, -NH2 in CNX films CNX films CNX films CNX films CNX films CNX films CNX films CNX films CNX films Bibliography [1] [DLC4-1] B. Dischler, A. Bubenzer and P. Koidl, Appl. Phys. Lett. 42, (1983) 636 [2] [DLC4-7] G. Herzberg, Infrared and Raman spectra of polyatomic molecules, Van Nostrand, Prin-centon N.J., 1945 [3] [DLC4-8] F. R. Dollish, W. G. Fateley and F. F. Bently, Characteristic Raman frequencies, Wiley, New York, 1974 [4] [DLC4-6] = [DLC3] [5] [HMDS016-28] S. Y. Park, N. Kim, U. Y. Kim, S. Hong and H. Sasabe, Polym. J. 22, (1990) 242 [6] [HMDS016-29] A. C. Dillon, M. Robinson, M. Y. Han and S. M. George, J. Electrochem. Soc. 139, (1992) 537 [7] [HMDS014-14] A. M. Wrobel, M. R. Wertheimer, J. Dib, H. P. Schreiber, J. Macromol. Sci.-Chem. 14, (1980) 321 [8] [HMDS014-15] I. Tajima, M. Yamamoto, J. Polym. Sei. 23, (1985) 615 [9] [HMDS014-16] G. J. Vandentop, M. Kawasaki, R. M. Nix, I. G. Brown, M. Salmeron, G. A. Somorjai, Phys. Rev. B41, (1990) 3200 [10] [HMDS014-17] K. Kashiwagi, Y. Yoshida, Y. Murayama, Jpn. J. Apl. Phys. 8, (1991) 1803 [11] [HMDS014-18] L. J. Bellamy, Ultrarot-Spectroskopie und chemische Konstitution, Steinkoff, 2 Aufl., Darmstadt 1966 37