Conduction and switching characteristics of III-V Schottky rectifiers for low loss switching

The authors report on the fabrication and evaluation of silicon and gallium arsenide switching diode technology. It is noted that the benefit of fabricating Schottky rectifiers using gallium arsenide material compared to silicon is an order of magnitude improvement in switching speed at voltages above 200 V. Gallium arsenide rectifiers also have the benefit of lower drift region ON resistance compared to silicon. Unfortunately the benefit of the reduction in drift region assistance is not realized due to the limited control of the barrier height. The barrier height of metals in contact with gallium arsenide is fairly independent of the metal. Understanding the surface physics of wide bandgap semiconductors and a fundamental understanding of the metal-semiconductor interface will be required before the ON resistance benefit of gallium arsenide can be realized. However, gallium arsenide Schottky rectifiers with significant speed performance at voltages up to 400 V justify the selection of this technology for high-frequency power conversion applications