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A gas-phase reaction mechanism is proposed for the chemical vapor deposition (CVD) of amorphous silicon from silane or disilane at atmospheric pressure. The gas stream in the CVD reactor is populated by silanes, silylenes, and disilenes in a variety of sizes. Silylenes form by the decomposition of silanes, and they rapidly insert into other silanes to form larger silanes. Although silylenes are expected to stick to growth surfaces to which they diffuse, they are too reactive in the gas phase to deliver a large flux onto the growth surface. Larger silylenes (SiH3SiH and larger) also isomerize to form less reactive disilenes, which we propose to be principally responsible for film growth. Film profiles observed in depositions from silane and disilane are presented, and computed film profiles are compared to these observations. Deposition from silane is explained quite well by the mechanism, as are some qualitative features of deposition from disilane.

SiO2 films were deposited in a commercial single wafer parallel plate plasma deposition reactor using tetraethoxysilane as the silicon source. Deposition conditions were varied to produce films with widely differing properties. Electrical, optical, mechanical, and wet-etch-rate characterization were then used to investigate the as-deposited film quality. Moisture uptake was also measured and related to the initial properties. The films were studied in an ongoing investigation of silicon dioxide interlevel dielectric films used in multilevel ultra large scale integrated chip wiring. ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.163.2.206 Downloaded on 2016-06-15 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.163.2.206 Downloaded on 2016-06-15 to IP

The qualities of plasma-enhanced chemical vapor deposited (PECVD) silicon nitride films can be improved by increasing the deposition temperature. This report compares PECVD silicon nitride films to low pressure chemical vapor deposited (LPCVD) films. The dependence of the film properties on process parameters, specifically power and temperature, are investigated. The stress is shown to shift from tensile to compressive with increasing temperature and power. The deposition rate, uniformity, wet etch rate, index of refraction, composition, stress, hydrogen content, and conformality are considered to evaluate the film properties. Temperature affects the hydrogen content in the films by causing decreased incorporation of N-H containing species whereas the dependence on power is due to changes in the gas-phase precursors. All PECVD film properties, with the exception of cenformality, are comparable to those of LPCVD films.

Gas‐phase reaction mechanisms are proposed for the chemical vapor deposition (CVD) of silicon dioxide false(SiO2false) from silane or disilane with nitrous oxide at atmospheric pressure. Observed SiO2 growth profiles are presented, and computed profiles are compared to these observations. The deposition of silicon dioxide from silane and excess nitrous oxide is hypothesized to be a chain reaction initiated by the decomposition of N2O . SiH3 attack on N2O , and SiH3O attack on SiH4 , are the propagating reactions. SiH3OH is posited to be the film precursor, which is rapidly oxidized and dehydrogenated on the growth surface. SiH3OH is also posited as an intermediate in the formation of other (non‐depositing) oxidized by‐products. The proposed mechanism accounts for a weak dependence of the peak growth rate on initial silane concentration and a strong dependence on nitrous oxide. The decomposition of Si2H6 is proposed to initiate the deposition of silicon dioxide from disilane in a large excess of nitrous oxide. Rapid reaction of the decomposition product, SiH2 , with N2O suppresses the formation of larger silicon hydrides, generating the oxide film precursor, silanone false(SiH2Ofalse) . Besides the film, oxidized by‐products are also formed from SiH2O . This second mechanism accounts for a strong dependence of the peak growth rate on initial disilane concentration and a weak dependence on nitrous oxide. At lower N2O concentrations, both of the above mechanisms, as well as silicon hydride reactions, participate to a significant extent, resulting in silicon‐rich oxide films, SiOx . Under these conditions, oxidized species containing more than one silicon atom are also suspected of participating in the deposition.