It is an object of the invention to provide a method for producing an IC chip capable of producing an IC chip with a thickness as extremely thin as 50 µm or thinner, for example, about 25 to 30 µm at a high productivity. The invention is a method for producing an IC chip, which comprises; at least a step 1 of fixing a wafer in a support plate by sticking the wafer to the gas generating agent-containing face of a pressure sensitive adhesive double-faced tape having a pressure sensitive adhesive layer containing a gas generating agent for generating a gas by light radiation in at least one face; a step 2 of grinding the wafer in a state of being fixed in the support plate through the pressure sensitive adhesive double-faced tape; a step 3 of radiating light to the pressure sensitive adhesive double-faced tape; and a step 4 of separating the pressure sensitive adhesive double-faced tape from the wafer, a gas releasing speed from the pressure sensitive adhesive double-faced tape being 5 L/cm 2 ·min or higher in the step 3.
