Silicon-on-insulator (soi) substrate and method of fabricating the same

Abstract

There is provided a method of fabricating a silicon-on-insulator substrate, including the steps of (a) forming a silicon substrate at a surface thereof with an oxygen-containing region containing oxygen at such a concentration that oxygen is not precipitated in the oxygen-containing region in later mentioned heat treatment, (b) forming a silicon oxide film at a surface of the silicon substrate, (c) implanting hydrogen ions into the silicon substrate through the silicon oxide film, (d) overlapping the silicon substrate and a support substrate each other so that the silicon oxide film makes contact with the support substrate, and (e) applying heat treatment to the thus overlapped silicon substrate and support substrate to thereby separate the silicon substrate into two pieces at a region into which the hydrogen ions have been implanted, one of the two pieces remaining on the silicon oxide film as a silicon-on-insulator active layer. The support substrate, the silicon oxide film located on the support substrate, and the silicon-on-insulator active layer formed on the silicon oxide film defines a silicon-on-insulator structure. The method makes it possible to significantly reduce crystal defect density in the silicon-on-insulator active layer, which ensures that a substrate made in accordance with the method can be used for fabricating electronic devices thereon.