Semiconductor device and method for manufacturing the same

Abstract

A semiconductor device includes a semiconductor substrate which has a first main surface having circuit elements formed thereon, a second main surface substantially opposite to the first main surface, and a plurality of side faces provided between the first main surface and the second main surface. The semiconductor device also includes a plurality of external terminals formed over the first main surface and respectively electrically connected to the circuit elements. The second main surface has a central area and a peripheral area surrounding the central area, and a first steplike section formed in the peripheral area.

What is claimed is:  
     
         1 . A semiconductor device comprising: 
 a semiconductor substrate having a first main surface having circuit elements formed thereon, a second main surface substantially opposite to the first main surface, and a plurality of side faces provided between the first main surface and the second main surface; and a plurality of external terminals formed over the first main surface and respectively electrically connected to the circuit elements,    wherein the second main surface has a central area and a peripheral area which surrounds the central area, and a first steplike section is formed in the peripheral area.    
     
     
         2 . The semiconductor device according to  claim 1 , wherein the first steplike section has a predetermined width formed along the plurality of side faces.  
     
     
         3 . The semiconductor device according to  claim 1 , wherein the first steplike section has a first portion having a first width formed along a first side face of the plurality of side faces, and a second portion having a second width which is formed along a second side face opposite to the first side face and is narrower than the first width.  
     
     
         4 . The semiconductor device according to  claim 1 , wherein the second main surface further has a second steplike portion which extends from the first side face of the plurality of side faces to the second side face of the plurality of side faces, which is opposite to the first side face.  
     
     
         5 . The semiconductor device according to  claim 1 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         6 . The semiconductor device according to  claim 2 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         7 . The semiconductor device according to  claim 3 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         8 . The semiconductor device according to  claim 4 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         9 . A semiconductor device comprising: 
 a semiconductor substrate having a first main surface having circuit elements formed thereon, a second main surface substantially opposite to the first main surface, and a plurality of side faces provided between the first main surface and the second main surface; and a plurality of external terminals formed over the first main surface and respectively electrically connected to the circuit elements,    wherein the second main surface has a central area and a peripheral area which surrounds the central area, the distance from the first main surface to the second main surface is a first distance in the central area, and the distance from the first main surface to the second main surface is a second distance shorter than the first distance in the peripheral area.    
     
     
         10 . The semiconductor device according to  claim 9 , wherein the distance from the first main surface to the second main surface corresponds to the second distance within a range of a third distance from the first side face of the plurality of side faces to the central area, and corresponds to the second distance within a range of a fourth distance which extends from the second side face opposite to the first side face, of the plurality of side faces and is shorter than the third distance.  
     
     
         11 . The semiconductor device according to  claim 9 , wherein the distance from the first main surface to the second main surface in the peripheral area becomes gradually short from the central area to the respective side faces.  
     
     
         12 . The semiconductor device according to  claim 9 , wherein the distance from the first main surface to the second main surface in a predetermined area of the central area substantially corresponds to the second distance.  
     
     
         13 . The semiconductor device according to  claim 9 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         14 . The semiconductor device according to  claim 10 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         15 . The semiconductor device according to  claim 11 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         16 . The semiconductor device according to  claim 12 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         17 . A semiconductor device comprising: 
 a semiconductor substrate having a first main surface having circuit elements formed thereon, a second main surface substantially opposite to the first main surface, and a plurality of side faces provided between the first main surface and the second main surface; and a plurality of external terminals formed over the first main surface and respectively electrically connected to the circuit elements,    wherein the second main surface has a central area and a peripheral area which surrounds the central area, and the peripheral area is rougher than the second main surface in the central area.    
     
     
         18 . The semiconductor device according to  claim 17 , wherein a predetermined area of the central area is rougher than other areas of the central area.  
     
     
         19 . The semiconductor device according to  claim 17 , wherein a sealing resin is formed on the first main surface and the external terminals are exposed from the surface of the sealing resin.  
     
     
         20 . The semiconductor device according to  claim 18 , wherein a sealing resin is formed on the first main surface and the external terminals are exposed from the surface of the sealing resin.  
     
     
         21 . A semiconductor device comprising: 
 a semiconductor substrate having a first main surface having circuit elements formed thereon, a second main surface substantially opposite to the first main surface, and a plurality of side faces provided between the first main surface and the second main surface; and a plurality of external terminals formed over the first main surface and respectively electrically connected to the circuit elements,    wherein the second main surface has a central area and a peripheral area which surrounds the central area, a steplike section is formed in the peripheral area, the thickness of the semiconductor substrate is a first thickness in the central area, and a second thickness thicker than the first thickness in the peripheral area.    
     
     
         22 . The semiconductor device according to  claim 21 , wherein the thickness of the semiconductor substrate corresponds to the second thickness in a first area from a first side face of the plurality of side faces to the central area and corresponds to the second thickness in a second area which extends from a second side face opposite to the first side face, of the plurality of side faces to the central area and is narrower than the first area.  
     
     
         23 . The semiconductor device according to  claim 21 , wherein the thickness of the semiconductor substrate in the peripheral area becomes gradually thin from the central area to the respective side faces.  
     
     
         24 . The semiconductor device according to  claim 21 , wherein the thickness of the semiconductor substrate in a predetermined area of the central area substantially corresponds to the second thickness.  
     
     
         25 . The semiconductor device according to  claim 21 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         26 . The semiconductor device according to  claim 22 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         27 . The semiconductor device according to  claim 23 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.  
     
     
         28 . The semiconductor device according to  claim 24 , wherein a sealing resin is formed on the first main surface, and the external terminals are exposed from the surface of the sealing resin.