Patent ID: 8042441

Claim:
An apparatus for cutting a protective tape of a semiconductor wafer for cutting a protective tape applied on a surface of the semiconductor wafer along a contour of the wafer by rotating and traveling a cutter blade along an outer circumferential edge of the semiconductor wafer, the apparatus comprising: a pushing biasing device configured to apply a biasing force by pushing the cutter blade to the outer circumferential edge of the semiconductor wafer with an elastic restoring force of a spring so as to apply a constant pushing biasing force facing to the outer circumferential edge of the semiconductor wafer during the rotating and traveling of the cutter blade, the cutter blade movably supported in a radial direction of the wafer; a pushing-hack device for applying a pushing back force smaller than the pushing biasing force in a direction opposite to the pushing bias direction with respect to the cutter blade when the cutter blade travels along the outer circumferential edge of the semiconductor wafer; and a controlling device for automatically controlling the pushing back force applied by the pushing back device corresponding to a variation of a traveling speed of the cutter blade such that the controlling device detects an amount of traveling from the start point of time of traveling of the cutter blade, calculates the variation of the speed based on a detection result, and controls the air pressure of the air cylinder based on an information on an obtained variation.