Semiconductor device

Abstract

A semiconductor device according to the present invention includes: a body region of a first conductive type; trenches formed by digging in from a top surface of the body region; gate electrodes embedded in the trenches; source regions of a second conductive type formed at sides of the trenches in a top layer portion of the body region; and body contact regions of the first conductive type, penetrating through the source regions in a thickness direction and contacting the body region. The body contact regions are formed in a zigzag alignment in a plan view. With respect to a column formed by the body contact regions aligned in a predetermined column direction, the trenches are disposed at both sides in a row direction orthogonal to the column direction in a plan view, extend in the column direction, and form meandering lines each connecting a plurality of curved portions so that a predetermined gap in the row direction is formed respectively between adjacent trenches extending in the column direction and between the trenches and the body contact regions.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a body region of a first conductive type;   trenches formed by digging in from a top surface of the body region;   gate electrodes embedded in the trenches;   source regions of a second conductive type formed at sides of the trenches in a top layer portion of the body region; and   body contact regions of the first conductive type, penetrating through the source regions in a thickness direction and contacting the body region; and   wherein the body contact regions are formed in a zigzag alignment in a plan view,   with respect to a column formed by the body contact regions aligned in a predetermined column direction Y, the trenches are disposed at both sides in a row direction X orthogonal to the column direction Y in a plan view, extend in the column direction Y, and form meandering lines each connecting a plurality of bent portions so that a predetermined gap D in the row direction X is formed respectively between adjacent trenches extending in the column direction Y and between the trenches and the body contact regions, and   the bent portions are bent at an inner angle greater than 90 degrees.   
     
     
         2 . The semiconductor device according to  claim 1 , wherein the bent portions are bent at an inner angle of 120 degrees. 
     
     
         3 . The semiconductor device according to  claim 1 , further comprising:
 a semiconductor substrate of a second conductive type, the substrate made of a silicon substrate having top and bottom sides; and   an epitaxial layer of a second conductive type, the epitaxial layer made of silicon layer formed on the top side of the substrate; wherein   the body region is formed on the epitaxial layer, and   the trenches extends from a top side of the body region to the epitaxial layer.   
     
     
         4 . The semiconductor device according to  claim 1 , further comprising:
 gate insulating films, each of the gate insulating films covering the surface of a respective one of the trenches to form an insulating trough; wherein   each of the gate electrodes completely filling a respective one of the insulating troughs with the gate electrodes coming up to the top of the troughs.   
     
     
         5 . The semiconductor device according to  claim 1 , wherein
 the body contact regions are disposed in a plurality of columns that extend at a fixed pitch in the column Y direction when seen in a plan view, and   in a pair of columns that are adjacent one another in the row direction X, the body contact regions forming one of the columns and the body contact regions forming the other of the columns are in a positional relationship of being shifted in the column direction Y by half of the fixed pitch.   
     
     
         6 . The semiconductor device according to  claim 1 , wherein the body contact regions are substantially square in shape, with sides parallel to the row direction X or the column direction Y, when seen in a plan view. 
     
     
         7 . The semiconductor device of  claim 1 , wherein the semiconductor device is a vertical MOSFET having a trench gate structure. 
     
     
         8 . The semiconductor device of  claim 3 , wherein bottoms of the trenches are in the epitaxial layer. 
     
     
         9 . The semiconductor device of  claim 8 , wherein the body contact regions are much deeper than the regions surrounding the body contact regions.