Compositional and electrical properties of Si metal–oxide–semiconductor structure prepared by direct photoenhanced chemical vapor deposition using a deuterium lamp

Abstract

High quality SiO2 layers have been grown on (111) Si substrates by direct photoenhanced chemical vapor deposition using monosilane (SiH4) and oxygen (O2) as gas sources under irradiation of a deuterium lamp. The refractive index of the deposited oxide is 1.462 at 250 °C when the gas ratio (O2/SiH4) is 5. The measurements of the Fourier transform infrared spectrum, x-ray photoelectron spectroscopy, and Auger electron spectroscopy show that the dominant components of the oxide are silicon and oxygen and the film is SiO2. Hysteresis free capacitance–voltage characteristics of the metal–oxide–semiconductor diode was observed. After low temperature postoxidation annealing, the minimum interface trap density is 1.5×1011 cm−2 eV−1, which is comparable to that of thermal oxidation.