Patent ID: 7351645

Claim:
A pressure sensitive adhesive sheet, being used in a method for producing a semiconductor chip, wherein the method comprises the steps of: forming a groove having depth smaller than thickness of a wafer on a surface of the wafer on which a semiconductor circuit is formed; reducing the thickness of the wafer and finally dividing the wafer into individual chips by grinding a back face of the wafer; the pressure sensitive adhesive sheet, comprising a rigid substrate, a vibration relaxation layer provided on one face of the rigid substrate and a pressure sensitive adhesive layer provided on the other face of the rigid substrate, wherein thickness of the rigid substrate is 10 to 150 μm and Young's modulus thereof is 1000 to 30000 MPa; and thickness of the vibration relaxation layer is 5 to 80 μm and a peak value of tan δ of dynamic viscoelasticity thereof at −5° C. to 120° C. is 0.5 or more.