Semiconductor device

Abstract

A horizontal semiconductor device having multiple unit semiconductor elements, each of said unit semiconductor element formed by an IGBT including: a semiconductor substrate of a first conductivity type; a semiconductor region of a second conductivity type formed on the semiconductor substrate; a collector layer of the first conductivity type formed within the semiconductor region; a ring-shaped base layer of the first conductivity type formed within the semiconductor region such that the base layer is off said collector layer but surrounds said collector layer; and a ring-shaped first emitter layer of the second conductivity type formed in said base layer, wherein movement of carriers between the first emitter layer and the collector layer is controlled in a channel region formed in the base layer, and the unit semiconductor elements are disposed adjacent to each other.

What is claimed is: 
     
         1 . A horizontal semiconductor device, comprising:
 a semiconductor substrate of a first conductivity type;   a semiconductor region of a second conductivity type formed on said semiconductor substrate;   a collector layer of the first conductivity type formed within said semiconductor region;   a base layer of the first conductivity type formed within said semiconductor region such that said base layer is off said collector layer; and   a first emitter layer of the second conductivity type formed in said base layer, wherein movement of carriers between said first emitter layer and said collector layer is controlled in a channel region formed in said base layer, wherein   a region of the first conductivity type is disposed in said semiconductor region to contact with the bottom surface of said base layer.   
     
     
         2 . A horizontal semiconductor device, comprising:
 a semiconductor substrate of a first conductivity type;   a semiconductor region of a second conductivity type formed on said semiconductor substrate;   a collector layer of the first conductivity type formed within said semiconductor region;   a base layer of the first conductivity type formed within said semiconductor region such that said base layer is off said collector layer; and   a first emitter layer of the second conductivity type formed in said base layer, wherein movement of carriers between said first emitter layer and said collector layer is controlled in a channel region formed in said base layer, wherein   said first emitter layer includes an endless main region and convex areas which outwardly protrude from said main region, the gap (W 1 ) between two adjacent convex areas is wider than the width (W 2 ) of said convex area (W 1 >W 2 ), and is connected with said emitter electrode at these convex areas.   
     
     
         3 . A horizontal semiconductor device, comprising:
 a semiconductor substrate;   a semiconductor region of a second conductivity type formed on said semiconductor substrate;   a collector layer of the first conductivity type formed within said semiconductor region;   an endless base layer of the first conductivity type formed within said semiconductor region such that said base layer is off said collector layer but surrounds said collector layer; and   an endless first emitter layer of the second conductivity type formed in said base layer, wherein movement of carriers between said first emitter layer and said collector layer is controlled in a channel region formed in said base layer, wherein   an insulation film is disposed between said semiconductor substrate and said semiconductor region, and   said first emitter layer is formed by an endless main region and convex areas which outwardly protrude from said main region, the gap (W 1 ) between two adjacent convex areas is wider than the width (W 2 ) of said convex area (W 1 >W 2 ), and is connected with said emitter electrode at these convex areas.   
     
     
         4 . The semiconductor device according to  claim 3 , wherein the end of said convex area comprises a tip area which extends along the direction of the tangent line to said main region, and said tip area is connected with said emitter electrode. 
     
     
         5 . The semiconductor device according to  claim 1 , wherein a second emitter layer of the first conductivity type is disposed in said base layer so as to surround said first emitter layer. 
     
     
         6 . A horizontal semiconductor device having multiple unit semiconductor elements, each of said unit semiconductor element formed by an IGBT comprising:
 a semiconductor substrate of a first conductivity type;   a semiconductor region of a second conductivity type formed on said semiconductor substrate;   a collector layer of the first conductivity type formed within said semiconductor region;   a base layer of the first conductivity type formed within said semiconductor region such that said base layer is off said collector layer; and   a first emitter layer of the second conductivity type and a second emitter layer of the first conductivity type formed in said base layer, wherein movement of carriers between said first emitter layer and said collector layer is controlled in a channel region formed in said base layer, wherein   a region of the first conductivity type is disposed within an area surrounded by said second emitter layers included in adjacent two unit semiconductor elements and a common contact line to these two second emitter layers.   
     
     
         7 . A horizontal semiconductor device having multiple unit semiconductor elements, each of said unit semiconductor element formed by an IGBT comprising:
 a semiconductor substrate;   a semiconductor region of a second conductivity type formed on said semiconductor substrate;   a collector layer of the first conductivity type formed within said semiconductor region;   a base layer of the first conductivity type formed within said semiconductor region such that said base layer is off said collector layer; and   a first emitter layer of the second conductivity type and a second emitter layer of the first conductivity type formed in said base layer, wherein movement of carriers between said first emitter layer and said collector layer is controlled in a channel region formed in said base layer, wherein   an insulation film is disposed between said semiconductor substrate and said semiconductor region, and   a region of the first conductivity type is disposed within an area surrounded by said second emitter layers included in adjacent two unit semiconductor elements and a common contact line to these two second emitter layers.