Electrical properties of Al foil-4H-SiC Schottky junctions fabricated by surface-activated bonding

摘要

We fabricate 17-mu m-thick Al foil-4H-SiC Schottky junctions by surface-activated bonding. Their current-voltage and capacitance-voltage characteristics are compared with those of Schottky junctions fabricated by evaporating Al layers on n-4H-SiC epilayers. We find that the ideality factor of Al foil/SiC junctions is larger than that of conventional junctions, which is due to the irradiation of the fast atom beam (FAB) of Ar. The ideality factor of Al foil/SiC junctions is improved by annealing at 400 degrees C. We also find that the Schottky barrier height is increased by FAB irradiation, which is likely to be due to the negative charges formed at SiC surfaces. (C) 2018 The Japan Society of Applied Physics