Novel Electrical Characterization of Thin 3C-SiC Films on Si Substrates

Abstract

Thin semiconductor films provide many functional uses in the fields of electronics, sensors, optics, and microelectro-mechanical systems (MEMS). A prime example is the case of thin film 3C-Silicon Carbide epitaxially grown on standard silicon wafers. The required SiC layer thickness for these applications ranges from a few nanometers to a few microns, and process conditions that control film stress, doping type and concentration, crystal orientation, and surface roughness need to be developed along with accurate physical and electrical characterization techniques. In this paper, we present two novel variations on established measurement techniques. Firstly, the hotprobe technique is used as a simple, non-destructive method to monitor film doping and crystal quality based on the open circuit voltage and short circuit currents. Results are presented for both ntype and p-type films grown on (100) and (111) silicon orientations, and supported by transmission electron micrographs and X-ray diffraction data. Secondly, a technique based on the four point resistivity measurement is used to determine film resistivity while eliminating the errors introduced by substrate leakage.