The surface modification of Si(1 1 1) substrates with SiN x for the growth of high quality β-SiC epilayers

Abstract

Single crystal β-SiC(1 1 1) epilayers were grown on Si(1 1 1) substrates whose surface had been modified with SiN x . When the SiC epilayers were grown on clean Si surfaces, voids were observed in the silicon side of the SiC/Si interface. Their formation was attributed to the out-diffusion of Si atoms from the Si substrate during the growth of the SiC epilayer. But void-free SiC epilayers with a flat and smooth interface were grown on Si surfaces nitrided for times longer than 30 min. Crystalline quality of β-SiC grown on a Si substrate nitrided for 60 min was better than that grown on a clean Si substrate. The silicon nitride films completely suppressed the formation of voids even for an extended growth time of 300 min.