Main questions about GaN
Because gallium nitride is a wide-bandgap semiconductor, and its polarity is too large, it is more difficult to obtain better metal-semiconductor ohmic contact through high doping. This is a difficult problem in the manufacture of GaN devices, so the performance of GaN devices is often good or bad. It is related to the production result of ohmic contact. A better solution now is to use a heterojunction. First, let the band gap gradually transition to a smaller one, and then use high doping to achieve ohmic contact, but this process is more complicated. In short, ohmic contact is a major problem that needs to be solved in the manufacture of GaN devices.
The application prospects of gallium nitride
For gallium nitride materials, the heteroepitaxial defect density is quite high due to the unresolved substrate single crystal for a long time, but the device level is already practical. In the future, it will be possible to combine with AlGaP and AlGaAs red LEDs to form a bright and full-color display. In this way, the white light source mixed with the three primary colors also opens up new application areas, and the era characterized by high reliability and long-life LED will come. Both fluorescent lamps and light bulbs will be replaced by LEDs. LED will become the leading product, and GaN transistors will also develop rapidly with the development of material growth and device technology, becoming a new generation of high-temperature, high-power devices.
The research and application of gallium nitride materials are the current frontier and hotspot of global semiconductor research. It is a new type of semiconductor material for the development of microelectronic devices and optoelectronic devices. Together with semiconductor materials such as SIC and diamond, it is known as the successor to the first generation of Ge and Si. Semiconductor materials, second-generation GaAs, InP compound semiconductor materials, and third-generation semiconductor materials. It has a wide direct bandgap, strong atomic bonds, high thermal conductivity, good chemical stability (hardly corroded by any acid), and strong anti-radiation ability. It is used in optoelectronics, high temperature, and high power devices, and high There are broad prospects in the application of high-frequency microwave devices.