4H-SiC trench filling by chemical vapor deposition using trichlorosilane as Si-species precursor

Abstract

4H-SiC trench filling has been accomplished by chemical vapor deposition (CVD) with a gas system composed of trichlorosilane, (TCS:C2H4:H2). The influences of Cl/Si ratio and growth pressure on the coverage distribution across trenches and the corresponding filling efficiency were investigated. Using the optimized process at Cl/Si = 43.5, the 8 μm deep 4H-SiC trenches with an aspect ratio of 3, were completely filled at a filling rate of 2.8 μm/h and acquired a flat end surface without void defects.