Defects in Cubic SiC on Si

Abstract

Defects in both as-grown and neutron irradiated n- and p-type epitaxially grown cubic silicon carbide (3C-SiC) on Si (100) substrates have been characterized electrically. Due to the lattice mismatch the SiC-Si interface has a large density of dislocations. Electronically active states associated with this interface are observed in thin n-type material. Thicker layers of n- and p-type cubic SiC are free of electronically active deep levels. Deep Level Transient Spectroscopy (DLTS) measurements of neutron irradiated material indicate an electron trap at Ec-0.49 eV in n-type material and three hole traps at Ev + 0.18 eV, Ev + 0.24 eV, and Ev + 0.51 eV in p-type material. Resistivity measurements in conjunction with the DLTS studies indicate that most of the radiation induced defects are in the middle third of the 3C-SiC bandgap. Ninety percent of the neutron irradiation defects anneal at 350°C, indicating that 3C-SiC is a promising material for device operation at high temperatures and in radiation fields.