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Removed from the deposition region, an upstream hydrogen microwave plasma generates arsenic hydrides by etching the surface of solid arsenic. The hydrides are transported to the deposition region and mixed with trimethylgallium to achieve low temperature (350°-400°C) and low pressure (750 mtorr) homoepitaxial GaAs films. Low precursor V:III ratios are used to achieve homoepitaxial films with high levels of carbon dopants (l019 to mid 1020 cm−3). No active or afterglow plasma exists in the growth region. The observed homo epitaxial growth activation energies of 54 kcal/mole and 66 kcal/mole for films deposited with V:III ratios of 1:1 and 1:4, respectively, are in the range of those reported for the heterogeneous decomposition of trimethylgallium in the absence of arsine. The films are found to be of good crystalline quality via double crystal x-ray rocking curves. The majority carriers are holes and have hole concentrations that correlate to the carbon doping, as determined by room temperature Hall effect measurements and secondary ion mass spectroscopy. Carrier mobility versus carbon concentration is also presented.

A downstream near afterglow plasma was used to deposit epitaxial GaAs at substrate temperatures as low as 300 °C. Feedstock organometallics of trimethylgallium and trimethylarsenic were employed at a ratio of 1:2, respectively. The observed growth rate varies with the substrate temperature, but no growth occurs without the plasma. Scanning electron microscopy electron backscattering was used to probe the single crystal quality of the deposited layers.

In situ generated arsenic hydrides are reacted downstream with trimethylgallium (TMGa), both in the presence of and in the absence of a downstream hydrogen afterglow plasma. The homoepitaxial activation energy dramatically changes from 62 kcal/mol for the pure thermal to 21 kcal/mol for the plasma‐assisted growth. The carbon incorporation mechanism for the plasma‐assisted growth at temperatures less than 400 °C has a distinct activation energy for carbon incorporation of 23 kcal/mol, independent of V‐III ratios. At temperatures above 400 °C, the level of carbon incorporated in the films reaches a level that appears to be dependent on the gas‐phase precursor V‐III ratio. The activation energy of the low‐temperature region is consistent with the surface decomposition of arsenic hydrides.

Removed from the deposition region, an upstream hydrogen microwave plasma etches a surface of solid arsenic located downstream to generate arsenic hydrides. The latter are used with trimethylgallium (TMGa) to achieve low temperature (400–490° C) and low pressure (750 mTorr) homoepitaxial GaAs films. No active or afterglow plasma exists in the growth region. The homoepitaxial growth activation energy of 62 kcal/mole is consistent with the heterogeneous decomposition of TMGa in the absence of arsine. Precursor V-III ratios as low as 0.25 are used to achieve homoepitaxial films, but with high levels of carbon impurities (1019 to mid 1020 cm−3). Carbon incorporation increases at low V-III ratios (0.25 to 0.5) for increasing temperatures with an activation energy of 23 kcal/mole. As the V-III ratios are increased above 1.0, the carbon incorporation activation energy decreases slightly to 15 kcal/mole.

Removed from the deposition region, an upstream hydrogen microwave plasma generates arsenic hydrides by etching the surface of solid arsenic. The hydrides are transported to the deposition region and mixed with trimethylgallium to achieve low temperature (350–400 °C) and low pressure (750 mTorr) homoepitaxial GaAs films. Low precursor V/III ratios are used to achieve homoepitaxial films with high levels of carbon dopants (1019 to mid 1020 cm−3). No active or afterglow plasma exists in the growth region. The observed homoepitaxial growth activation energies of 54 kcal/mole and 66 kcal/mole for films deposited with V/III ratios of 1/1 and 1/4, respectively, are in the range of those reported for the heterogeneous decomposition of trimethylgallium in the absence of arsine. The majority carriers are holes and have hole concentrations which correlate to the carbon doping, as determined by room temperature Hall effect measurements and secondary ion mass spectroscopy. Carrier mobility versus carbon concentration...

A spatially confined disk shaped hydrogen plasma is used for plasma assisted organometallic vapor phase epitaxy (PAOMVPE) of GaAs at substrate temperatures from 245–430°C. Feedstock gases, trimethylgallium (TMGa) and trimethylarsenic (TMAs), are introduced downstream from the disk shaped plasma in the near afterglow. Dissociation of the organometallics is dominated by VUV photons and metastable species energy transfer reactions rather than non-selective electron impact. At the temperatures employed no thermal CVD occurs. An Arrhenius plot of the growth rate shows a low activation of 3 Kcal/mole for surface mobility. The transitional temperature from amorphous to homoepitaxial growth (300°C) is determined via electron diffraction patterns from deposited films versus substrate temperature. Increases in the feedstock gas V-III ratio resulted in decreases in absolute carbon concentration in the deposited films.

The electron beam assisted chemical vapor deposition of silicon nitride anti-reflection coatings onto thin film CdS/CuInSe2 solar cells and the resultant effects on their performance are reported. In some cases large increases in the short circuit current open circuit voltage and fill factor were observed. The present results are explained by the usual index matching anti-reflection mechanisms and either the passivation of undesirable shunts or improvement of intrinsic diode characteristics.

Silicon nitride films have been deposited using an electron beam created plasma in a silane, ammonia, and nitrogen mixture. The films were deposited at substrate temperatures between 50 and 400 °C. Physical, chemical, and electrical properties of these films are reported.

A glow discharge electron beam has been used to deposit silicon dioxide (Si0 2 ) and silicon nitride (Si 3 N 4 ) films for microelectronic applications. Electron beam assisted CVD is a new technique in which the reaction volume is defined mainly by the geometry of the electron beam and offers the possibility of uniform deposition over large areas. The Si0 2 films were deposited in silane-nitrous oxide-nitrogen mixtures, and the Si 3 N 4 films were deposited in silane-ammonia-nitrogen mixtures. The films were deposited with a 2-4 kV electron beam parallel to the sample, at 0.1-1 Torr pressures, and at substrate temperatures from 50-400°C. The index of refraction, sthoichiometry, pinhole density, etch rate, conformal step coverage, and hydrogen bonding were measured.

An ArF excimer laser was used to photochemically deposit thin films of silicon dioxide, silicon nitride, aluminum oxide and zinc oxide at low temperatures (100-500°C) for microelectronic applications. High depo-sition (>1000 A/Min) rates and conformal step coverage were obtained. The hydrogen bonding, pinhole density, index of refraction, etch rate, and breakdown voltage have been measured for the Si02 and silicon nitride films. The effect of substrate temperature and ArF (193 nm) surface photons on the physical, chemical and electrical properties of Si02 films have been investigated.© (1984) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Here we report on the electrical properties of laser-assisted chemical vapor deposited (CVD) aluminum oxynitride (AION) films on InP substrates for use as metal–insulator–semiconductor (MIS) diodes. From previous investigations, the major problems associated with InP MIS devices related to current drift phenomena and interfacial instabilities. These instabilities depend on surface preparation and surface damage induced during insulator deposition. Laser-assisted CVD may provide a less radiation damaging deposition technique, and thus InP MIS devices may be improved.