Gallium diode

Fig. 12. Details of an aluminum gallium arsenide semiconductor diode laser.

Photodetectors operate by carrier transport across a semiconductor junction. A wide variety of these photodiodes are available, such as Schottky diodes, phototransistors, and avalanche photodetectors. Typical photodetector materials are gallium arsenic phosphide and gallium phosphide, which are produced by MOCVD or MBE. 

Soft, silver white metal that melts in the hand (29.8 °C) and remains liquid up to 2204 °C (difference 2174 °C, suitable for special thermometers). Gallium is quite widespread, but always in small amounts in admixtures. Its "career" took off with the advent of semiconductors. Ga arsenide and Ga phosphide, which are preferential to silicon in some applications, have extensive uses in microchips, diodes, lasers, and microwaves. The element is found in every mobile phone and computer. Ga nitride (GaN) is used in UV LEDs (ultraviolet light-emitting diodes). In this manner, a curiosity was transformed into a high-tech speciality. 

Chan K., Ito H., Inaba H., Optical remote monitoring of methane gas using low-loss optical fiber link and indium gallium arsenide phosphide light-emitting diode in 1.33-mm region, Appl. Phys. Lett. 1983 43 634. 

Colorless gas with a mild odor described as fishy or like garlic. It is detectable at 0.5 ppm. Used as a doping agent for solid-state electronic components, in the preparation of gallium arsenide and glass dyes, and in the manufacture of light-emitting diodes. 

Gallium(III) azide, 72 360 Gallium-based laser diodes, 72 349 Gallium chalcogenides, 72 359 Gallium compounds, 72 344, 355-361 with ammonia, 72 357-358 with phosphorus, arsenic, and antimony, 72 360... 

Uses. The main uses of gallium is in the manufacture of semiconductors which are generally obtained by the combination of Ga with P and As. Gallium arsenide is capable of converting electricity directly into coherent light (production of light-emitting diodes). 

The gallium aluminum arsenide (GaAlAs) and indium phosphide (InP) laser diodes are among the most used NIR excitation sources (Figure 7.4). These diodes are... 

Antimony alloys have many commercial applications. The metal makes its alloys hard and stiff and imparts resistance to corrosion. Such alloys are used in battery grids and parts, tank linings, pipes and pumps. The lead plates in the lead storage batteries constitute 94% lead and 6% antimony. Babbit metal, an alloy of antimony, tin, and copper is used to make antifriction machine bearings. Alloys made from very high purity grade antimony with indium, gallium and bismuth are used as infrared detectors, diodes, hall effect devices and thermoelectric coolers. 

The industrial application of SiC began with the blue light emitting diode (LED), which was very weak due to the indirect bandgap of SiC but was the only commercial blue electroluminescent light source at the time (the late 1980s). The SiC blue LED was soon surpassed in intensity by the gallium nitride (GaN)-based... 

In a laser diode, population inversion of charge carriers in a semiconductor is achieved by a very high electric field across a pn junction in gallium arsenide. Most laser diodes operate at red and near-infrared wavelengths (680-1 550 nm). 

Gallium-based laser diodes have also lost some of the market in telecommunications to indium-based devices. Optical fiber systems moved to the use of longer wavelengths for long distance networks. 

Light-emitting diodes -arsenic m [ARSENIC AND ARSENIC ALLOYS] (Vol 3) -gallium and indium nitrides in [NITRIDES] (Vol 17) -germaniumm [GERMANIUM AND GERMANIUMCOMPOUNDS] (Vol 12) -phosphorus compounds m [PHOSPHORUS COMPOUNDS] (Vol 18) -use m biosensors [BIOSENSORS] (Vol 4)... 

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