A wafer is divided at division starting points along division lines to form a predetermined gap between adjacent chips. Next, that area of a tape to which the wafer is adhered is suction held by a table, after which the table and a ring frame holding section are relatively moved further away from each other to expand the tape in a ring shape between an outer periphery of the wafer and an inner periphery of a ring frame. Thereafter, the table and the ring frame holding section are relatively moved closer to each other to slacken the ring-shaped tape, and the ring-shaped tape is heated by a heater, to heat shrink the tape and to maintain the predetermined gap between the adjacent chips.