Pattern Etching of Crystalline SiC by KrF Excimer Laser

Abstract

SiC exhibits a high resistance to heat and X-rays. With its characteristics, it is expected as a semiconductor material with which IC devices for car and space electronics can be developed. Minute pattern etching of SiC is, however, very difficult chemically or physically. Here, we propose a new photochemical pattern etching method, in which the crystalline SiC surface in an atmosphere of gaseous CIF₃ was etched by patterned KrF excimer laser light. The KrF laser beams were irradiated to the SiC substrate: one parallel and the other perpendicular to the substrate surface. The parallel beam was used to dissociate CIF₃ gas in the proximity of the substrate, and the perpendicular beam which was projected circuit pattern was used to locally excite the substrate. The line and space of the single crystalline SiC (3C-type) was 1 µm; etching depth, 1000 Å.