Study on large size and low leakage SiC diode detector for nuclear radiation detection

Abstract

A 4H-SiCPiN detector for nuclear radiation detection has been successfully fabricated with a device size of10mm∗10mm. An epitaxial layer with a doping concentration of less than 2.0∗1014 cm−3 and a thickness of 30μm was grown on the N+ substrate as the detector drift region. Then a highly doped P+ epitaxial layerwas grown with a doping concentrationhigher than 2∗1019cm−3. In this paper, the simulation, the fabrication, and the electrical characteristics of 4H-SiC PiN detector were reported. An dry etch mesa structure was used as detector termination structure to avoid field crowding at the edage of device and improve the device performance. A leakage current of 18nA was measured at a cathode bias of 600 V from the 4H-SiC PiN detector. And the device shows a forward voltage drop of 2.7V with a forward current of 10mA. Anuclear radiation detection result used this SiCPiN detector was also reported.