Laser-Assisted Phatoelectrochemical Etching of n-type Beta-SiC

In this paper a nonthermal photoelectrochemical etching technique for β–SiC is reported. The measured etch rates of 1–100 μm/min in this process are much faster than other etching methods currently available for this material. UV radiation is necessary for efficient photogeneration of holes near the surface. These holes are transported in the presence of an external bias to the semiconductor/liquid interface, where dissolution occurs through the anodic oxidation of the SiC and the removal of the oxide by F^– ions present in the electrolyte. The electrochemistry of ß–SiC and the etching process variables are discussed.