MOS Capacitors Fabricated on 3C-SiC(111) Layers Grown on 6H-SiC(0001)

Abstract

In this work we report on the various steps, from growth to processing, required for the fabrication of metaloxide-semiconductor (MOS) capacitors using 3C-SiC(111) material and with superior interfacial quality. The layers were first heteroepitaxially grown by vapour-liquid-solid mechanism on 6H-SiC(0001) substrate. Then the surface was polished before homoepitaxial thickening by chemical vapour deposition. On such 3C-SiC material, the MOS capacitors were fabricated using an advanced oxidation process combining Plasma-Enhanced Chemical Vapour Deposition of SiO2 and short post-oxidation steps in wet oxygen (H2O:O2). Electrical measurements of these MOS capacitors led to very low density of interface traps, D it = 1.2 × 1010 eV−1 cm−2 at 0.63 eV below the conduction band, and fixed oxide charges Q eff /q estimated to −7 × 109 cm−2. These characteristics, which are, to the author’s knowledge, the best values found for SiC based MOS capacitors, represent a significant advance towards the fabrication of MOS devices based on 3C-SiC.