Communication—The Role of the Metal-Semiconductor Junction in Pt-Assisted Photochemical Etching of Silicon Carbide

Abstract

Porous 4H-SiC layers were fabricated by photochemical etching of n-type 4H-SiC samples with varying resistivity. An etching solution of Na 2 S 2 O 8 and HF was used while Pt deposited at the 4H-SiC surface served as catalyst for the reduction of Na 2 S 2 O 8 . The contact resistance at the Pt/4H-SiC junction was decreased by annealing and surface near phosphorous doping. This enabled the porosification of 4H-SiC with photochemical etching.