The development of the third generation semiconductor materials and devices represented by GaN (Dan Huajia) is the core and foundation of the emerging semiconductor industry, and its research and development is developing rapidly. In the GaN based optoelectronic devices, the blue LED LED is the first to achieve commercialized production. After the successful development of blue light LED and LD, the research direction is transferred to the GaN UV detector. GaN material has great application market in microwave power. Gallium nitride semiconductor switches are known as a new milestone in the design of semiconductor chips. Scientists at University of Florida have developed an important device that can be used to make new electronic switches. This electronic switch can provide smooth and continuous power supply.