The (100) surface of gallium arsenide was examined during and after exposure to liquid methanol and 0.05N methanolic potassium hydroxide, using surface infrared spectroscopy in the multiple internal reflection mode. Liquid methanol dissolves components of the natural oxide present at the semiconductor surface (
, 690 cm−1, and a sub‐oxide of gallium or arsenic, 765 cm−1) and leaves behind a persistent physisorbed layer following evaporation. The natural oxide regrows at a rate of approximately 10Å per hour, while methanol is still adsorbed at the surface, indicating that the layer is non‐protective. Methanolic potassium hydroxide etches the gallium arsenide surface, most likely via a two‐step oxidation/ dissolution process. Methanolic 
also leaves a layer of crystalline potassium methoxide on the surface following evaporation, as evidenced by absorption bands at 1059 cm−1 (C‒O stretch) and 2812 and 2924 cm−1 (
stretches).
Source:IOPscience
Gallium arsenide crystals were synthesized by the horizontal Bridgman method in neutron‐activated boats of natural and synthetic fused quartz. Instrumental radiochemical techniques were applied to determine the silicon concentrations from Si31 radioactivity measurements and to identify other trace elements transferred to the gallium arsenide during the process. All crystals were found completely enveloped in an impurity‐enriched surface layer containing silicon concentrations up to 1500 ppm. Bulk concentrations of silicon ranged from 
, and varied in different sections of the crystals within a factor of 1.7. Evidence of several types of transfer mechanisms was obtained. Other impurities that originated from natural fused quartz and were detected in the form of their radioactive isotopes in the crystals include copper, gallium, antimony, and gold at concentrations below 1016 atoms/cm3; the concentrations of these contaminants were effectively decreased by use of high‐purity synthetic quartz.
Source:IOPscience
Fabrication processes have been developed for gallium arsenide phosphide Schottky‐barrier field effect transistor (SBFET) on an insulating gallium arsenide substrate. Process techniques as well as results of electrical characterization of the device structure including the 
interface are described. Formation of a conductive layer near the 
interface is postulated, and an anlaysis of its effects on transistor characteristics is presented.
Source:IOPscience
Gallium arsenide has been used to fabricate variable reactance and computer diodes which compare favorably with the best commercially available of germanium and silicon. The diodes have been fabricated by zinc diffusion into n‐type gallium arsenide. Ohmic contact to the n‐type material has been made with an antimony‐gold alloy and to the p‐type side with indium. Etching is used to remove the p‐type diffused skin from everywhere but under the indium contact, thereby forming the mesa and defining the p‐n junction area. Rectification ratios (at 2 v) as high as 1010 have been achieved. The diodes have been operated successfully in a variable reactance amplifier at S‐band (2800 mcps) and in millimicrosecond‐switching computer circuits.
Source:IOPscience
This paper describes the growth of polycrystalline films of gallium arsenide on molybdenum substrates with an intermediate layer of germanium. The gallium arsenide layer is grown by the reaction of trimethylgallium and arsine in a cold‐wall reactor system. Germanium layers are formed by vacuum evaporation, as well as by the pyrolysis of germane gas. Techniques are described for minimizing massive autodoping effects which are commonly observed in the heteroepitaxy of these semiconductors. Doping concentrations in the range of 
are obtained for the gallium arsenide film. Schottky diodes, fabricated in this material, exhibit avalanche breakdown in the range of 30–35V.
Source:IOPscience
Gallium arsenide is the most important of the class of semiconducting compounds made by combining elements in groups III and V of the periodic table. Early work on these compounds suggested that gallium arsenide was the material most likely to yield a range of devices capable of operating at higher ambient temperatures and higher powers than was possible with germanium or silicon. A comparison of the properties of silicon, germanium and gallium arsenide is made in table 1, from which it can be seen that gallium arsenide has the highest energy gap and has also a high electron mobility.
Source:IOPscience
