Very thin oxide film on a silicon surface by ultraclean oxidation

Very thin oxide films with a high electrical insulating performance have been grown by controlling preoxide growth using the ultraclean oxidation method. The current level through the ultraclean oxide is lower than that through the conventional dry oxide including thicker preoxide. The barrier height at the silicon-oxide interface for electrons emission from silicon to oxide for the ultraclean oxide is little decreased as the thickness is thinner, while the barrier height for conventional dry oxide is drastically decreased. The growth rate of ultraclean oxide at 900°C is governed by a simple parabolic law even in the range of 5-20 nm.