Wafer processing method

A wafer processing method is used in processing a wafer including a device area and a peripheral marginal area surrounding the device area. The device area has a plurality of devices and an electrode connected to each device. The wafer processing method includes the steps of cutting a first area of the peripheral marginal area, fixing the front side of the wafer through an adhesive to a carrier substrate, grinding a back side of the wafer, supplying a chemical solution to the back side of the wafer to thereby etch the wafer such that the electrode projects from the back side of the wafer, forming an insulating film on the back side of the wafer, cutting a second area of the peripheral marginal area, the second area being not in contact with the adhesive, thereby removing the second area, and polishing the insulating film.