Semiconductor device having a metal silicide layer connecting two semiconductors

Claim 1

A semiconductor device comprising: a substrate formed of a semiconductor material of one conductivity type; a first semiconductor region of an opposite conductivity type formed on a surface area of said semiconductor substrate so that said first semiconductor region and the semiconductor substrate have a first common flat surface; an insulating layer formed on said substrate and said first semiconductor region to cover said substrate and said first semiconductor region, said insulating layer having a contact hole therein to expose an upper surface of said first semiconductor region; a conductive layer of metal silicide formed in said contact hole of said insulating layer to fill the contact hole of said insulating layer, said conductive layer having a thickness substantially the same as that of said insulating layer so that the insulating layer and the conductive layer have a second common flat surface; and a second semiconductor region formed of polycrystalline silicon of the first conductivity type formed on the second common flat surface of said insulating layer and conductive layer formed in said contact hole so that the first and second semiconductor regions are electrically connected via said conductive layer; said first semiconductor region, conductive layer and second semiconductor region being arranged in a thickness direction of said substrate in sequence recited herein.