Effects of Ar inductively coupled plasma exposure on 4H-SiC Schottky rectifiers

Abstract

4H-SiC Schottky rectifiers were exposed to inductively coupled Ar plasmas as a function of source power (150–750 W), rf chuck power (75–350 W), and process pressure (5–30 mTorr). The reverse breakdown voltage (VB) was increased by increases in both incident ion energy and ion flux, with the former having the strongest influence. As an example, Ar plasma exposure at ion energies of ∼335 eV led to an increase in VB from approximately −500 to −950 V. These results suggest strategies for minimizing plasma-induced damage during both deposition and etching steps used in the fabrication of SiC rectifiers.