Method For Manufacturing Semiconductor Device Using Mold Having Resin Dam And Semiconductor Device

Abstract

The suppression of resin leakage is combined with the suppression of damage to the functional wiring area of a wiring board in forming an encapsulation resin. A method for manufacturing a semiconductor device includes the step of clamping a wiring board with a first mold and a second mold. The second mold includes: a flat portion contacting a wiring board; a recessed portion forming a cavity to form an encapsulation resin; and a projecting portion formed at a location spaced apart from the recessed portion on the flat portion, the projecting portion projecting on the first mold side, and extending along the first edge of the wiring board.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a wiring board having opposite first and second surfaces, the first surface including a first region and a second region surrounding the first region, the wiring board when seen in a plane view including a first edge;   a semiconductor device mounted over the first region;   an encapsulation resin formed over the first region and encapsulating the semiconductor device, the encapsulation resin not being formed over the second region;   an external terminal formed on the second surface; and   a dent formed in the second region at a location spaced apart from the first region, the dent extending along the first edge.   
     
     
         2 . The semiconductor device according to  claim 1 ,
 wherein the wiring board includes:
 a base substrate formed with a plurality of through holes; 
 a first interconnection formed over the base substrate on the first surface side; and 
 a first insulating film formed over the first interconnection; 
   wherein the dent is formed on the first insulating film; and   wherein the through holes include a first through hole located in the second region and on the first region side on an inner side of the dent, when seen in a plane view.   
     
     
         3 . The semiconductor device according to  claim 2 ,
 wherein a depth of the dent is shallower than a thickness of the first insulating film over the first interconnection.   
     
     
         4 . The semiconductor device according to  claim 2 ,
 wherein the wiring board includes a first electrode terminal in the first region;   wherein the first interconnection extends from the first electrode terminal to the first through hole; and   wherein the wiring board further includes a second interconnection in the second region, the second interconnection reaching the first edge from the first through hole.   
     
     
         5 . The semiconductor device according to  claim 1 ,
 wherein the first region is an octagon comprising long sides alternating with short sides;   wherein when seen in a plane view, a first long side of the octagon and the first edge of the wiring board are parallel to each other and located on a same side relative to the first region; and   wherein the dent and the first long side extend in parallel with each other.   
     
     
         6 . The semiconductor device according to  claim 5 ,
 wherein a first distance between the first long side and the dent is longer than a second distance between the first edge and the dent.   
     
     
         7 . The semiconductor device according to  claim 5 ,
 wherein the dent is not formed in at least a part of a region proximate to the short side of the first region.   
     
     
         8 . The semiconductor device according to  claim 1 ,
 wherein when seen in a plane view, the external terminal located on an outermost peripheral portion of the second surface is still located in the first region on an inner side of the dent.   
     
     
         9 . The semiconductor device according to  claim 1 ,
 wherein the dent is formed by transferring a projecting portion of a resin encapsulation mold for use in encapsulating the encapsulation resin, the projecting portion being formed on a surface of the mold contacting the wiring board.   
     
     
         10 . The semiconductor device according to  claim 1 ,
 wherein a thin resin burr is formed over the second region between the dent and the first region, but not formed over the second region on the first edge side of the dent.   
     
     
         11 . A semiconductor device comprising:
 a wiring board having opposite first and second surfaces, the first surface including a first region and a second region surrounding the first region, the wiring board when seen in a plane view including a first edge;   a semiconductor device mounted over the first region;   an encapsulation resin formed over the first region and encapsulating the semiconductor device, the encapsulation resin not being formed over the second region;   an external terminal formed on the second surface; and   one or more resin burrs extending over the second region, in a direction of the first edge of the wiring board from the encapsulation resin, the one or more resin burrs extending no further than an imaginary line which extends along and between a long side of the encapsulation resin and the first edge of the wiring board.   
     
     
         12 . The semiconductor device according to  claim 11 , wherein the wiring board includes:
 a base substrate formed with a plurality of through holes, including a first through hole located in the second region on an inner side of the imaginary line;   a first electrode terminal in the first region;   a first interconnection formed over the base substrate on the first surface side, the first interconnection extending from the first electrode terminal to the first through hole; and   a second interconnection in the second region, the second interconnection reaching the first edge from the first through hole.   
     
     
         13 . The semiconductor device according to  claim 11 ,
 wherein the first region is an octagon comprising long sides alternating with short sides;   wherein when seen in a plane view, a first long side of the octagon and the first edge of the wiring board are parallel to each other and located on a same side relative to the first region; and   wherein the imaginary line and the first long side extend in parallel with each other.   
     
     
         14 . The semiconductor device according to  claim 13 ,
 wherein a first distance between the first long side and the imaginary line is longer than a second distance between the first edge and the imaginary line.   
     
     
         15 . The semiconductor device according to  claim 11 ,
 wherein when seen in a plane view, an external terminal located on an outermost peripheral portion is still located in the first region.