Encapsulation method for ball grid array semiconductor package

Abstract

An encapsulation method for a ball grid array (BGA) semiconductor package, includes: adhering one sided adhesive tape to an upper portion of the semiconductor package after performing a wire bonding; carrying out a molding by using a mold having a groove of a certain size inside; and removing the one side adhesive tape after completing the molding, whereby a flash is prevented from occurring during the BGA encapsulation process.

What is claimed is:  
     
         1 . An encapsulation method for a ball grid array (BGA) semiconductor package, comprising: 
 adhering adhesive tape to an upper portion of a printed circuit board on which wiring exists, thereby defining a cavity of a predetermined size between adjacent edges of pieces of the adhesive tape;    positioning a mold on the printed circuit board to which the adhesive tape is adhered;    injecting a liquid epoxy through a through hole of the mold to cover the upper portion of the printed circuit board which is exposed through the cavity with the liquid epoxy; and    removing the mold and the adhesive tape.    
     
     
         2 . The encapsulation method of  claim 1 , wherein the adhesive tape has adhesive on only one side.  
     
     
         3 . The encapsulation method of  claim 1 , wherein a width of the cavity defined by the adhesive tape is sufficiently large to be sealed up by the liquid epoxy.  
     
     
         4 . The encapsulation method of  claim 1 , wherein a width of the cavity defined by the adhesive tape is smaller than a width of a groove formed at an upper portion of the mold.  
     
     
         5 . The encapsulation method of  claim 1 , wherein a thickness of the adhesive tape is approximately 20 μm.  
     
     
         6 . The encapsulation method of  claim 1 , wherein an adhesive is spread at a portion of the adhesive tape facing the printed circuit board.  
     
     
         7 . The encapsulation method of  claim 6 , wherein the adhesive loses its adhesive property as the molding is performed.  
     
     
         8 . An encapsulation method for a ball grid array semiconductor package, comprising: 
 adhering adhesive tape to an upper portion of a printed circuit board on which wiring exists, thereby defining a cavity of a predetermined size between adjacent edges of pieces of the adhesive tape;    surrounding the entire package including the adhesive tape with a mold;    injecting a liquid epoxy through a through hole of the mold to cover the upper portion of the printed circuit board which is exposed through the cavity with the liquid epoxy; and    removing the mold and the adhesive tape.    
     
     
         9 . The encapsulation method of  claim 8 , wherein the adhesive tape has adhesive on only one side.  
     
     
         10 . The encapsulation method of  claim 8 , wherein a width of the cavity defined by the one side adhesive tape is sufficiently large to be sealed up by the liquid epoxy.  
     
     
         11 . The encapsulation method of  claim 8 , wherein a width of the cavity defined by the adhesive tape is smaller than that of a groove formed at an upper portion of the mold.  
     
     
         12 . The encapsulation method of  claim 8 , wherein a thickness of the adhesive tape is approximately 20 μm.  
     
     
         13 . The encapsulation method of  claim 8 , wherein an adhesive is spread at a portion of the adhesive tape facing the printed circuit board.  
     
     
         14 . The encapsulation method of  claim 13 , wherein the adhesive loses its adhesive property as the molding is performed.  
     
     
         15 . An encapsulation method for a ball grid array semiconductor package, comprising: 
 placing a mask on surface portions of a printed circuit board of a semiconductor device, areas between adjacent portions of the mask defining areas of the semiconductor device that will be exposed to liquid epoxy;    applying liquid epoxy to areas of the semiconductor device that are exposed by the mask; and    removing the mask to expose surface portions of the semiconductor device not covered by the liquid epoxy.    
     
     
         16 . The method of  claim 15 , wherein the mask is an adhesive tape.  
     
     
         17 . The method of  claim 16 , wherein the adhesive tape has adhesive on only one side, the adhesive side being placed on the surface portions of the semiconductor device.  
     
     
         18 . The method of  claim 15 , wherein applying the liquid epoxy further comprises: 
 positioning a mold over surface portions of the semiconductor device, the mold having grooves that are positioned over the areas of the semiconductor device defined by the mask and exposed to the liquid epoxy; and    injecting the liquid epoxy through at least one hole in the groove of the mold.    
     
     
         19 . The method of  claim 16 , wherein the adhesive tape loses its adhesive property when predetermined thermal conditions are experienced.