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The microstructures and electro-optical properties of thermally evaporated indium-oxide films are given and discussed. It is shown that highly transparent and conducting films can be prepared at relatively low (-150~ substrate temperatures, with and without doping by tin. Results of stoichiometry measurements in conjunction with the Hall effect and crystal structure data suggest the existence of indium atoms with different valences in these films. This implies that the conduction mechanism in this material may be more complicated than hitherto assumed.

Chlorine has been incorporated into SiO2 films by thermal oxidation of Si in a mixture of O2 and HCl gases. Mobile sodium ions adsorbed on the oxide surface were drifted to the Si-SiO2 interface (0.5 MV cm−1 bias at 200 °C). Passivation, defined as the fraction of mobile sodium charge neutralized, exhibited a pronounced threshold with HCl content in the growth ambient. This was partly due to a similar variation of oxide chlorine content (measured by α-particle backscattering). For fixed growth temperature, passivation was a monotonic function of oxide chlorine content, and was only weakly dependent on the level of sodium contamination over the range 5×1011 to 1×1013 Na/cm2.

As much as 10 is C1/cm 2 has been incorporated into SiO2 thin films by thermal oxidation of Si in mixture of 02 and HC1 gases. The chlorine concentration and location in the oxide film were determined by Rutherford backscattering of ~ particles. The oxide preparation conditions included the growth temperature range from 1150 ~ to 1300~C, the growth time range of 15-60 min, and gas phase HC1/O2 concentrations in the range of 0-10 volume percent (v/o). The total chlorine concentration in the oxide film increased monotonically with the HC1 content of the growth ambient. The increase was linear at first, rose abruptly over a limited range of HC1/O2 concentration (above the so-called "thr, eshold"), and then again increased linearly at higher HC1/O2 concentrations. The threshold moved to lower HC1/O2 concentrations as either growth time or growth temperature was increased. The C1 concentration in the oxide film increased monotonically with growth time and growth temperature. For all growth conditions investigated, chlorine was found to be concentrated at or near the Si/SiO2 interface. Direct scanning electron microscopy and replication studies indicated that the oxide surface was uneven for oxides grown in HC1/O2 concentrations above threshold. The size of the surface features increased at higher HC1/O2 concentrations. This lateral nonuniformity did not appear in samples prepared in HC1/O2 concentrations below threshold. ExperimentalN-type, 5-10 ~-cm, arsenic-doped Si (100) substrates were used in this study. Oxidations were carried out on cleaned wafers in an rf-heated, cold-wall * Electrochemical Society Active Member. 1Present address: ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.218.248.209 Downloaded on 2015-03-16 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.218.248.209 Downloaded on 2015-03-16 to IP