Doping of 6H–SiC by selective diffusion of boron

Abstract

Experimental evidence of selective boron doping of 6H–SiC via diffusion is given. Selective diffusion has been realized at 1800–2100 °C using graphite film as a protecting mask. Cathodoluminescence measurements as well as an anodic oxidation technique have been employed to identify the local doped regions. In addition, a diffused planar p–n diode based on the local p-type emitter region was fabricated. The ideality factor extracted from current–voltage characteristics was 1.97, which indicates that the Shockley–Hall–Read recombination is the dominant mechanism in the conduction region. The value of breakdown voltage for this diode measured at room temperature was a little greater than 800 V, and a leakage current density of 5.7×10−6 A/cm2 at 800 V was achieved.