Gallium arsenide transistors

G.R. Antell, Gallium Arsenide Transistors T.L. Tansley, Heterojunction Properties... 

Many active electronic devices can be operated at cryogenic temperatures [45], They are generally of the field-effect transistor (FET) type and are based on silicon (working down to 100K) or gallium arsenide (working even below 4K). 

Gallium arsenide exhibits semiconductor properties. It is used in transistors, lasers, solar cells and various high-speed microcircuits. 

Gallium arsenide and silicon transistors each have their own specific advantages. ClaAs transistors switch faster than Si transistors and they also emit near-infrared and visible light, a property of value when both optical and electrical functions are combined in one chip. In many other respects, the GaAs devices are inferior to their silicon counterparts. Researchers have recently found how to effect epitaxial growth of crystalline GaAs layers... 

Fig. 9. A Schottky barrier gate used in the metal-semiconductor field-effect transistor (MESFET) in AT T gallium arsenide microchips. The tiny gate is only one micrometer wide (1/25,400 inch). The gate electrode is deposited before the ion-implantation process so that the gate material will shade the channel under it from the ion rain that doses the exposed material. (AT T Technology)...

Gallium arsenide s native oxide is found to be a mixture of nonstoichiometric galhum and arsenic oxides and elemental arsenic. Thus, the electronic band structure is found to be severely disrupted, causing a breakdown in normal semiconductor behavior on the GaAs surface. As a consequence, the GaAs MISFET (metal insulator semiconductor field-effect transistor) equivalent to the technologically important Si-based MOSFET (metal-oxide semiconductor field-effect transistor) is, therefore, presently unavailable. 

Some arsenic is used in the electronics industry. It is added to germanium and silicon to make transistors. A compound of arsenic, gallium arsenide (GaAs), is also used to make light-emitting diodes (LEDs). LEDs produce the lighted numbers in hand-held calculators, clocks, watches, and a number of other electronic devices. 

Gallium arsenide is also used to make transistors. A transistor is a device used to control the flow of electricity in a circuit. Gallium arsenide has many of the properties of a semiconductor. A semiconductor is a material that conducts an electrical current, but not as well as a metal, such as silver or copper. 

Gallium arsenide has one big advantage over silicon, another element used in transistors. Gallium arsenide produces less heat. Therefore,... 

Gallium arsenide is used in the production of transistors. MICHAEL ABBEY. SCIENCE SOURCE, THE NATIONAL AUDUBON SOCIETY COLLECTION/PHOTO RESEARCHERS, INC. 

M.I. Nathan and H. Heiblum, A Gallium Arsenide Ballistic Transistor, IEEE Spectrum 23, 45 (1986). 

In terms of semiconductor material as silicon, germanium, gallium arsenide, and silicon carbide transistors. 

Elemental silicon is central to the vast industry of solid-state electronics. Appropriately doped with other elements, it forms a variety of semiconductors that constitute most transistors and integrated circuits. Other elements and compounds such as germanium or gallium arsenide have also found a niche as semicondnctors in electronics, but silicon occupies the prime position. How fortunate that it is the second most abundant element in the Earth s crust. Its compounds with the most abundant crustal element, oxygen, are equally central in many different aspects of chromatography. Silica, silica gel, glass, qnartz, fused silica, and silicones all have a remarkable variety of key roles to play in chromatography. Let us familiarize ourselves with some of their relevant properties. 

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