Semiconductor device with base formed by the junction of two semiconductors of the same conductive type

Abstract

Abstract A semiconductor device, by which a base in which gates are buried can be formed by the junction of semiconductor substrates to each other at a lower temperature, and a fabrication process thereof are provided. Recesses are defined in the top of an N - substrate. A P + layer is formed on the underside of the N - substrate. P + -Gate regions are each formed in an area ranging from the bottom to lower side portions of the recesses. A metal layer composed of an Au-Sb alloy is formed on the underside of the N + substrate. The N - substrate and the N + substrate are subjected to a treatment for removing impurities thereon with an aqueous solution of sulfuric acid and hydrogen peroxide, washed with purified water and dried by a spin dryer. The N - substrate and the N + substrate are heated at about 350° C. in a hydrogen atmosphere in a state that the tops of projections between the recesses have been brought into contact with the metal layer provided on the underside of the N + substrate, whereby the N - substrate and the N + substrate are joined to each other.

Inventors

• 👤 Yoshio Terasawa

Bibliographic Details