silicon (SI), germanium (GE), compound semiconductor, such as gallium arsenide (GaAs), etc; Doping or making other compound semiconductor materials, such as boron (b), phosphorus (P), indium (in) and antimony (sb).
1.When semiconductor is stimulated by external light and heat, its conductivity will change significantly.
2.The conductivity of semiconductor is between conductor and insulator.
3. In pure semiconductors, adding a small amount of impurities will greatly enhance their conductivity
Gallium arsenide is an important GaAs semiconductor material. It belongs to group Ⅲ - Ⅴ compound semiconductor. Gallium arsenide is an important semiconductor material. It belongs to group Ⅲ - Ⅴ compound semiconductor. It belongs to sphalerite type lattice structure with lattice constant of 5.65 × 10-10m, band gap width 1.4 electron volts. Gallium arsenide was put into use in 1964.
GaAs material can be made into semi insulating high resistance materials with resistivity more than three orders of magnitude higher than that of silicon and germanium, which can be used to make infrared detectors, integrated circuit substrates, infrared detectors, etc γ Photon detector, etc.
Because its electron mobility is 5 ~ 6 times larger than that of silicon, it has been widely used in microwave devices and high-speed digital circuits. The semiconductor devices made of Stellite have the advantages of high frequency, high temperature, low temperature, low noise and strong radiation resistance，In addition, it can also be used to fabricate transfer devices and integrated effect devices. Beihua is one of the semiconductor materials with many advantages. However, the crystal triode made of Beihua is not suitable for high power devices because of its low magnification and poor thermal conductivity.
Although it has superior properties, because it decomposes at high temperature, it is technically necessary to grow high purity single crystal materials with ideal chemical ratio.