Charge Carriers Removal from 4H-SiC Using Field Enhanced by Optical Activation Diffusion Method

Abstract

This paper presents results of charge carriers removal from 4H-SiC wafers. A new chemical reactor has been tested for forced diffusion purification (reversed diffusion) of SiC films. Different types of conditions have been used to purify SiC samples. A 5 mW (630-680 nm) laser has been used to improve results. I-V characteristic curves have been measured to verify changes in electrical properties of the samples. SIMS has been used to analyze the concentrations of impurities in the SiC samples before and after treatment. It has been demonstrated that the field enhanced by optical activation diffusion method can remove impurities such as N and B form SiC films. As a result, the electrical properties of the SiC wafers have been significantly improved during treatment, especially in cases where a laser is emplaced.