Securing an ecological development of the society is closely linked with new ways of effective exploitation of available energy sources. One possibility is to minimize losses in electrical converters. To maximize the power in the same time, usage of the GaN-based power transistors is extremely useful.GaN is chemically stable semiconductor material with an energetic band-gap of 3.4 eV, which predestine its usage in hostile environment and at elevated temperature above 300 °C. Apart from that, high electron drift velocity of about 1 x 105 m/s provides GaN transistors with possibility to switch at high frequency. These material parameters are extremely useful for a construction of high power and frequency transistors and converters with high efficiency.
Basis of the invention is a vertical GaN transistor, consisting of an emitter electrode on the top contacting n+ GaN layer, collector electrode placed on a bottom of a GaN substrate and a gate electrode. Gate electrode is formed vertically along the insulating GaN channel and is separated from the GaN semiconductor by a dielectric insulator layer having a larger band-gap as for GaN. Insulating nature of the GaN channel provides for transistors an enhancement mode of operation, along with massive device construction without necessity of nano-patterning, parallel combination of channels, or air-bridge connections for the emitter.
High power vertical GaN transistors with insulating GaN channel will find exploitation by constructing highly effective electric converters. They will be used by energy generation and distribution, as well as in electric cars.
Patent application no. PP50074-2017