JPS6430247A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent an element substrate from electrical floatation and thereby to suppress fluctuations in the element substrate potential at the switching-on of the elements by a method wherein a layer serving virtually as a conductive layer is provided on the element substrate on its side nearer to an insulating substrate. CONSTITUTION:Into the side of an element substrate 1 in contact with an insulating substrate 4, As<+> is driven, producing an n<-> impurity diffusion layer 2 (to virtually serve as a conductive layer) near the surface. The element substrate 1 and a supporting substrate 3, made for example of n<+> silicon, are bonded together, and the combination is subjected to annealing. The surface (the side nearer to the element substrate 1) is converted into a mirror-finished surface 1a, a through-oxide film 5 is formed on its surface, and implantation of P<+> ions is accomplished for the formation of a substrate contact section 6 reaching the impurity diffusion layer 2. The through-oxide film 5 is removed and, by using the conventional technique, a field oxide film 7, a source electrode 8, a drain electrode 9, a gate electrode 10, an interlayer insulating film 11, aluminum layers 121-123, and a covering film 13 are provided.