Integration of microwave-annealed oxidation on germanium metal-oxide-semiconductor devices

Abstract

In this paper, a method that entails using microwave thermal oxidation to form a high-quality gate dielectric on Ge through surface passivation at considerably low temperatures (<400 degrees C) is presented. Formation of the GeOx layer was confirmed by x-ray photoelectron spectroscopy. To reduce the bulk trap density and interface trap density (D-it), microwave thermal oxidation was employed for post-deposition microwave thermal oxidation after the deposition of Al2O3 through atomic layer deposition. Tiny frequency dispersion in capacitance measurement and a low D-it value of 5.9 x 10(11) cm(-2) eV(-1) near the midgap confirmed a desirable passivation effect, which was favorable in mitigating the formation of dangling bonds on the Ge surface. A small hysteresis in capacitance was also observed, suggesting that the bulk dielectric was of high quality. On the basis of these characteristics, microwave-activated GeOx is a promising passivation layer material for aggressively scaled Ge-related metal oxide semiconductor devices. Published by the AVS.