Patent ID: 6731008
Filing Date: 2004-05-04
Classification: H01L

Abstract:
A semiconductor device having a conductive contact layer structure, comprising:first conductive layers formed on a main surface of a semiconductor substrate with an insulating film therebetween; a conductive region formed under and between said first conductive layer extending into the semiconductor substrate from, and having a junction surface intersecting, the main surface of said semiconductor substrate; a first insulation layer formed over an upper surface of said first conductive layer, having two side surfaces, one of said side surfaces reaching a surface of said first conductive region and the other of said side surfaces not reaching said surface of said conductive region; a second insulation layer having side surfaces formed on said first insulation layer with a high etching selectivity with respect to said first insulation layer; a first hole defined by the one of said side surfaces of said first insulation layer that reaches said surface of said conductive region; a second hole defined by the side surfaces of said second insulation layer in communication with said first hole; a sidewall insulation film formed at an inner sidewall of said second insulation layer defining said second hole, wherein said sidewall insulation film does not extend on said side surface of said first insulation layer that defines said first hole; and a second conductive layer formed inside said first and second holes so as to be electrically connected to said conductive region and to be electrically insulated from said first conductive layer, wherein the side surfaces of the first insulation layer defining the first hole are not aligned with the junction surface of the conductive region and the semiconductor substrate.