semiconductor device and a manufacturing method of the same

Abstract

A semiconductor device having a structure in which the structure is laminated in many stages is made thin. A reforming area is formed by irradiating a laser beam, where a condensing point is put together with the inside of the semiconductor substrate of a semiconductor wafer. Then, after applying the binding material of liquid state to the back surface of a semiconductor wafer by a spin coating method, this is dried and a solid-like adhesive layer is formed. Then, a semiconductor wafer is divided into each semiconductor chip by making the above-mentioned reforming area into a division origin. By pasting up this semiconductor chip on the main surface of the other semiconductor chip by the adhesive layer of the back surface, a semiconductor device having a structure in which the semiconductor device is laminated in many stages is manufactured.

1 . A manufacturing method of a semiconductor device, comprising the steps of:
 (a) providing a substrate having a main surface and a back surface opposing to the main surface;   (b) mounting a first semiconductor chip over the main surface of the wiring substrate via a first adhesive layer, wherein the first semiconductor chip has a first main surface, a first bonding pad formed on the first main surface and a first back surface opposing to the first main surface; and   (c) stacking a second semiconductor chip over the first semiconductor chip via a second adhesive layer such that a second back surface of the second semiconductor chip faces to the first semiconductor chip, wherein the second semiconductor chip has a second main surface, a second bonding pad formed on the second main surface and the second back surface opposing to the second main surface;   wherein the second semiconductor chip is formed by following steps (c1)-(c4):
 (c1) providing a semiconductor wafer having a third main surface, a plurality of third bonding pads formed on the third main surface, a cutting area formed on the third main surface, and a third back surface opposing to the third main surface; 
 (c2) applying a binding material of liquid state to the third back surface of the semiconductor wafer by a spin coating method; 
 (c3) heating the semiconductor wafer, and forming the second adhesive layer of solid state over the third back surface of the semiconductor wafer; and 
 (c4) cutting the semiconductor wafer along the cutting area, and obtaining the second semiconductor chip having the second adhesive layer formed over the second back surface of the second semiconductor chip from the semiconductor wafer. 
   
     
     
         2 . A manufacturing method of a semiconductor device according to  claim 1 , wherein the first adhesive layer is a film-like adhesion member. 
     
     
         3 . A manufacturing method of a semiconductor device according to  claim 1 , wherein a thickness of the second adhesive layer is thinner than that of the first adhesive layer.