Silicon nitride, hydrogen analysis

As a second example of the application of ion-beam analysis techniques to semiconductors, we take the calibration of IR absorption measurements of the hydrogen content of sputtered amorphous silicon and silicon nitride. In early measurements, the hydrogen content of glow-discharge a-Si H deduced from IR absorption measurements, using ablsinitio calculations of the absorption cross section of the Si—H IR absorption bands, was com-... 

For comparison values for Si3N4 films prepared by atmospheric-pressure CVD at 900°C from SiH4, NH3, N2 gas mixtures are also listed. Microchemical analysis data have shown that the chemical composition of the plasma silicon nitride films is slightly Si-rich at a Si/N-ratio between 0.8 and 1.0 compared to 0.75 for stoichiometric deposits. As indicated by infrared spectrometry, there are also larger amounts of hydrogen and traces of oxygen in the films. Therefore the true film composition may be represented by SxNyHz [195]. Films deposited at 300°C are thermally stable up to about 400°C. As a consequence of compressive film stress, blis-... 

The triaminosilane 2 is somewhat air- and moisture-sensitive but can be stored indefinitely in an inert atmosphere. Minor deviations in the elemental analysis data are due to the formation of silicon carbide and silicon nitride. It is highly soluble in common organic solvents. The solid-state structure of 2 has been determined by single-crystal X-ray analysis and shows nitrogen-hydrogen bridges. ... 

The refractive index of silicon nitride and silicon carbonitride thin films deposited at various temperatures is shown in Fig. 9. The re active index of silicon nitride has been well characterized and is generally reported to be between 1.8 and 2.1 [18]. The scatter in the reported values is largely attributed to variations in film stoichiometry and methods of deposition. The presence of impurities such as hydrogen, oxygen and firee silicon in particular, may also account for some of the r orted divergences. The measured refractive index of silicon nitride increased with deposition temperature from 1.82 to 1.95. Minor fluctuations in the atomic ratio of Si—to—N, that can be seen from the AES analysis (Kg. 7) may be responsible for the observed dependence of the refractive index on the deposition temperature. The refractive index for silicon carbonitride similarly ranged from 1.68 to 1.94. 

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