Adhesive sheet for affixation of a wafer and method for processing using the same

Abstract

An adhesive sheet for affixation of a wafer includes a first substrate, first adhesive layer arranged on the first substrate, second substrate arranged on the first adhesive layer, and second adhesive layer arranged on the second substrate. A chemical reaction which causes reduction in the adhesion of the first adhesive layer and a chemical reaction which causes reduction in the adhesion of the second adhesive layer are different. A method for processing using this sheet includes the steps of affixing the sheet to a wafer, dicing the wafer with the sheet affixed thereto, peeling the first substrate and first adhesive layer away from the diced wafer by reducing the adhesion of the first adhesive layer and, thereby, dividing the wafer into a plurality of chips, and peeling the second substrate and second adhesive layer away from each of the chips by reducing the adhesion of the second adhesive layer.

What is claimed is:  
     
         1 . An adhesive sheet for affixation of a wafer, comprising: 
 a first substrate;    a first adhesive layer arranged on the first substrate;    a second substrate arranged on the first adhesive layer; and    a second adhesive layer arranged on the second substrate,    wherein a chemical reaction which causes reduction in the adhesion of the first adhesive layer and a chemical reaction which causes reduction in the adhesion of the second adhesive layer are different.    
     
     
         2 . The adhesive sheet for affixation of a wafer according to  claim 1 , wherein: 
 the first adhesive layer comprises a radiation-setting adhesive; and    the second substrate comprises a heat-shrinkable plastic film.    
     
     
         3 . The adhesive sheet for affixation of a wafer according to  claim 1 , wherein: 
 the first substrate comprises a heat-shrinkable plastic film; and    the second adhesive layer comprises a radiation-setting adhesive.    
     
     
         4 . A method for processing using the adhesive sheet for affixation of a wafer according to  claim 1 , the method comprising the steps of: 
 affixing the sheet to the wafer;    dicing the wafer with the sheet affixed thereto;    peeling the first substrate and the first adhesive layer away from the diced wafer by reducing the adhesion of the first adhesive layer of the sheet and, thereby, dividing the wafer into a plurality of chips; and    peeling the second substrate and the second adhesive layer away from each of the chips by reducing the adhesion of the second adhesive layer of the sheet.    
     
     
         5 . A method for processing using the adhesive sheet for affixation of a wafer according to  claim 2 , the method comprising the steps of: 
 affixing the sheet to the wafer;    dicing the wafer with the sheet affixed thereto;    peeling the first substrate and the first adhesive layer away from the diced wafer by irradiating the first adhesive layer of the sheet with radioactive rays so as to cure the first adhesive layer and, thereby, dividing the wafer into a plurality of chips; and    peeling the second substrate and the second adhesive layer away from each of the chips by allowing the second substrate of the sheet to heat-shrink.    
     
     
         6 . A method for processing using the adhesive sheet for affixation of a wafer according to  claim 3 , the method comprising the steps of: 
 affixing the sheet to the wafer;    dicing the wafer with the sheet affixed thereto;    peeling the first substrate and the first adhesive layer away from the diced wafer by allowing the first substrate of the sheet to heat-shrink and, thereby, dividing the wafer into a plurality of chips; and    peeling the second substrate and the second adhesive layer away from each of the chips by irradiating the second adhesive layer of the sheet with radioactive rays so as to cure the second adhesive layer.