Gallium arsenide structure

Progress in semiconductor processing has evolved in a number of substrate materials, pre-destined for the use in micro structured devices, such as Silicon, Silicon-on-Insulator (SOI), Silicon Carbide and Gallium Arsenide [1]. 

Silicon is the most popular material for photovoltaic (PV) power. Another material is gallium arsenide (GaAs), which is a compound semiconductor. GaAs has a crystal structure similar to that of silicon, but it consists of alternating gallium and arsenic atoms. It is well suited for PV applications since it has a high light absorption coefficient and only a thin layer of material is required, which reduces the cost. 

The satellite would need 50 to 100 square kilometers of collector area using 14% efficient monocrystalline silicon solar cells. More expensive triple junction gallium arsenide solar cells with an efficiency of 28% would reduce the collector area by half. In both cases the solar station s structure would be several kilometers wide, making it much larger than most manmade structures on Earth. Building structures of this size in orbit has never been attempted before. 

The transfer gates 4 and the charge transfer gates 5 may be formed as MIS structures or as Schottky barrier structures using aluminium or platinum. Furthermore, the gallium arsenide substrate may be substituted for a silicon substrate. 

First-Principles Calculation of Energy Band Structure of Gallium Arsenide Crystals Using Madelung Potential... 

Abstract Energy band structure of gallium arsenide crystals is calculated by the... 

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