In order to grow silicon films with good crystal quality, it is important to remove oxygen and carbon contaminants on the surface and to obtain clean substrate surface immediately before growth. In conventional surface cleaning process, silicon substrate is heated up to about 1000 deg C and the surface contaminants are evaporated or gas-etched from the substrate surface. However, such high temperature treatment causes the redistribution of impurity atoms in the substrates and it makes difficult to fabricate fine structures. Recently, synchrotron radiation SR stimulated evaporation of SiO2 film and its application to surface cleaning at 650 deg C have been reported, and the usefulness of SR induced reactions for low-temperature process is being recognized. In this paper, we report on new SiO2 etching technique by the irradiation of SR in H2 atmosphere and on the application of this process to the pretreatment of Si film deposition. It is revealed that the addition of H2 gas during SR exposure is effective to increase the SiO2 etching rate and to reduce the carbon contamination on the Si substrate at low-temperature of 500 deg C.
This article is from 'Organization of the Optical Society of America Photonic Science Topical Meeting Series. Volume 3. The Microphysics of Surfaces: Beam-Induced Processes. Held in Santa Fe, New Mexico on 11-13 Feb 1991.' AD-A254 135,p122-125.