METHOD OF MANUFACTURING SOI SUBSTRATE AND METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

A first substrate of single-crystal silicon within which is formed an embrittled layer and over a surface of which is formed a first insulating film is provided; a second insulating film is formed over a surface of a second substrate; at least one surface of either the first insulating film or the second insulating film is exposed to a plasma atmosphere or an ion atmosphere, and that surface of the first insulating film or the second insulating film is activated; the first substrate and the second substrate are bonded together with the first insulating film and the second insulating film interposed therebetween; a single-crystal silicon film is separated from the first substrate at an interface of the embrittled layer of the first substrate, and a thin film single-crystal silicon film is formed over the second substrate with the first insulating film and the second insulating film interposed therebetween.