Fabrication and characteristics of bulk semi-insulating 6H-SiC semiconductor detector for an α radiation at room temperature

Abstract

The fully depleted SiC Schottky barrier detector was fabricated from a semi-insulating (SI) bulk crystal with a thickness of 388 μm and an orientation of the on axis (0 0 0 1). The bulk SI 6H-SiC detector structure consists of a Ni/Au contact at the Si-face and a Ti/Au contact at the C-face. The fabricated detector dimensions are 10×10 mm with a diameter of 6 mm for the contact dimension. The band gap of the 6H-SiC was determined by using an optical photon absorption spectroscopy in the ranges between 200 and 600 nm. The band gap of 6H-SiC is determined as 3.03 eV. The current density response according to the biased voltage was measured. The Schottky barrier height was determined as 0.86 eV on the basis of the thermo-ionic emission theory. The bulk SI 6H-SiC detector with a multi-layer structure, Au/Ni/6H-SiC/Ti/Au showed a good response for the α radiation in air and at room temperature.