Semiconductor device and method for the fabrication thereof

Abstract

Disclosed is a semiconductor device which comprises a semiconductor element having a plurality of electrodes, a plurality of external electrodes disposed around the periphery of the semiconductor element, a fine wire electrically connected between at least one of surfaces of each of the plural external electrodes and at least one of the plural electrodes of the semiconductor element, and an encapsulating resin which encapsulates the semiconductor element, the plural external electrodes, and the fine wires and whose external shape is a rectangular parallelepiped, wherein a bottom surface of the semiconductor element and a bottom surface of each of the plural external electrode are exposed from a bottom surface of the encapsulating resin and a top surface of the semiconductor element and a top surface of each of the plural external electrode are located substantially coplanar with each other.

What is claimed is:  
     
         1 . A method for the fabrication of a semiconductor device comprising the steps of: 
 (a) preparing a frame member;    said frame member including: 
 a plate-like frame major portion having a top surface and a bottom surface;  
 a plurality of electrode constituent portions which are projections formed on said top surface of said frame major portion; and  
 an element housing portion located in a top surface area of said frame major portion surrounded by said plural electrode constituent portions, said element housing portion housing therein a semiconductor element to be fixed thereto;  
   (b) fixing to said element housing portion of said frame member said semiconductor element having a plurality of electrodes;    (c) after said step (b), electrically connecting by a fine wire between at least one of said plural electrodes of said semiconductor element and at least one of top surfaces of said plural electrode constituent portions;    (d) encapsulating, by a resin, a surface of said frame member on the side where said semiconductor element has been fixed to said element housing portion and has been electronically connected by said fine wire; and    (e) after said step (d), grinding said frame major portion of said frame member such that said plural electrode constituent portions are separated from each other to become individual external electrodes, and exposing both a bottom surface of each of said plural external electrodes and a bottom surface of said semiconductor element from said resin.    
     
     
         2 . The method of  claim 1 , wherein said frame major portion of said frame member prepared in said step (a) is made of a metal plate or a conductive plate.  
     
     
         3 . The method of  claim 1 , wherein said frame member prepared in said step (a) has said plural electrode constituent portions each of which projects for substantially the same amount as the thickness of said semiconductor element to be fixed to said element housing portion.  
     
     
         4 . The method of  claim 1 , wherein said step (e) is carried out such that depressed portions recessed inside said resin are formed in surface areas of said resin, said resin surface areas being defined between external electrodes of said plural external electrodes and between said semiconductor element and an external electrode of said plural external electrodes, and said bottom surface of each of said plural external electrodes and said bottom surface of said semiconductor element being exposed from said resin.  
     
     
         5 . The method of  claim 1 , wherein said step (e) is carried out using a grinding member.  
     
     
         6 . The method of  claim 1 , 
 wherein said frame member prepared in said step (a) includes a plurality of said element housing portions;    wherein said step (b) is a step of fixing a plurality of said semiconductor elements to said plural element housing portions, respectively; and    wherein said method further comprises after said step (e): 
 a step of subjecting said plural semiconductor elements to characteristic testing; and  
 after said characteristic testing, a step of dividing said plural semiconductor elements into individual semiconductor device pieces, respectively.  
   
     
     
         7 . A method for the fabrication of a semiconductor device comprising the steps of: 
 (a) preparing a frame member;    said frame member including: 
 a plate-like frame major portion having a top surface and a bottom surface;  
 a plurality of electrode constituent portions which are projections formed on said top surface of said frame major portion, each of said plural electrode constituent portions having at its top surface a projecting stepped portion and a projected portion; and  
 an element housing portion located in a top surface area of said frame major portion surrounded by said plural electrode constituent portions, said element housing portion housing therein a semiconductor element to be fixed thereto;  
   (b) fixing to said element housing portion of said frame member said semiconductor element having a plurality of electrodes;    (c) after said step (b), electrically connecting by a fine wire between at least one of said plural electrodes of said semiconductor element and a top surface of at least one of said projecting stepped portions of said plural electrode constituent portions;    (d) encapsulating, by a resin, a surface of said frame member on the side where said semiconductor element has been fixed to said element housing portion and has been electrically connected by said fine wire;    (e) after said step (d), grinding said frame major portion of said frame member such that said plural electrode constituent portions are separated from each other to become individual external electrodes, and exposing both a bottom surface of each of said plural external electrodes and a bottom surface of said semiconductor element from said resin; and    (f) after said step (d), grinding a top surface of said resin on the side where said semiconductor element has been fixed to said element housing portion and has been electrically connected by said fine wire such that top surfaces of said projected portions are exposed from said resin top surface.    
     
     
         8 . A method for the fabrication of a semiconductor device comprising the steps of: 
 (a) preparing a frame member;    said frame member including: 
 a plate-like frame major portion having a top surface and a bottom surface;  
 a plurality of electrode constituent portions which are projections formed on said top surface of said frame major portion, each of said plural electrode constituent portions having at its top surface a projecting stepped portion and a projected portion and in its bottom surface a recessed portion; and  
 an element housing portion located in a top surface area of said frame major portion surrounded by said plural electrode constituent portions, said element housing portion housing therein a semiconductor element to be fixed thereto;  
   (b) fixing said semiconductor element having a plurality of electrodes to said element housing portion of said frame member;    (c) after said step (b), electrically connecting by a fine wire between at least one of said plural electrodes of said semiconductor element and a top surface of at least one of said projecting stepped portions of said plural electrode constituent portions;    (d) encapsulating, by a resin, a surface of said frame member on the side where said semiconductor element has been fixed to said element housing portion and has been electrically connected by said fine wire such that at least a top surface of each of said projected portions of said plural electrode constituent portions projects; and    (e) after said step (d), grinding said frame major portion of said frame member such that said plural electrode constituent portions are separated from each other to become individual external electrodes each having at its bottom surface said recessed portion, and exposing both a bottom surface of each of said plural external electrodes and a bottom surface of said semiconductor element from said resin.    
     
     
         9 . The method of  claim 8 , 
 wherein said frame member prepared in said step (a) includes a plurality of said element housing portions;    wherein said step (b) is a step of fixing a plurality of said semiconductor elements to said plural element housing portions, respectively; and    wherein said method further comprises after said step (e): 
 a step of forming a stacked structure by fitting said recessed portion in said bottom surface of said external electrode into a projected portion of a different semiconductor device, said projected portion being formed on an external electrode of said different semiconductor device so as to correspond to said recessed portion;  
 after said stacked structure formation step, a step of dividing said plural semiconductor elements in a stacked structure state into individual lamination type semiconductor devices, respectively.