PAM-XIAMEN provides GaAs epiwafer for MESFET devices, which is one FET epitaxial structure with modulated doping. Detailed epitaxial growth heterostructure is listed below for your reference. The electron migration rate of GaAs is 5.7 times higher than that of silicon, which is very suitable for high-frequency circuits. The electrical characteristics of GaAs modules in high frequency, high power, high efficiency and low noise index are far more than those of silicon modules. Therein, the depletion type MESFET based on GaAs hetero-epitaxial growth can have 80% power added efficiency under 3V voltage operation, which is very suitable for the requirements of long distance and long communication time in high tier wireless communication.
1. MESFET Epitaxial Growth of GaAs in 3inch
|In0.5Ga0.5P Stop Layer
|5.0х1017 cm – 3
|GaAs, AlGaAs Buffer
|GaAs (001) Substrate
2. About MESFET
MESFET (metal semiconductor field effect transistor) is a field-effect transistor composed of Schottky barrier gates. Compared with p-n junction gate field-effect transistor, it only uses metal semiconductor contact barrier to replace p-n junction gate, which has poor thermal stability, large leakage current, small logic swing and weak anti-noise ability. However, metal semiconductor contact can be formed at low temperature, and can be used not only for Si, but also for GaAs materials to produce transistors with excellent performance.
GaAs is often used as substrate for MESFET epitaxial film growth. A layer of n-GaAs is epitaxial on a semi insulating GaAs substrate to reduce the parasitic resistance. Schottky barrier is formed on top of N-type epitaxial layer by evaporation together with ohmic contact of source and drain electrodes. The metal semiconductor contact process allows the channel of MESFET to be shorter, which is conducive to improving the switching speed and operating frequency of the device. MESFET epitaxial growth semiconductor is widely used in wireless communication, information technology, phased array radar and other fields.
The Chinese government has announced new limits on the exportation of Gallium materials (such as GaAs, GaN, Ga2O3, GaP, InGaAs, and GaSb) and Germanium materials used to make semiconductor chips. Starting from August 1, 2023, exporting these materials is only allowed if we obtains a license from the Chinese Ministry of Commerce. Hope for your understanding and cooperation!