Method for simultaneously cutting multiple discs from a workpiece

Abstract

A method for sawing a semiconductor wafer. The method includes sawing a semiconductor ingot into workpieces and using a wire grid with fixed abrasive wires to move the workpiece toward the wire grid to saw the workpiece into slices. When the workpiece first contacts the wire grid, the initial cutting speed is less than 2 mm / min, the coolant flow is less than 0.1 l / h, and the wire speed is greater than 20 m / s. The workpiece is then guided through the wire grid until a first cutting depth is reached, and then the coolant flow is increased to at least 2000 l / h. The cutting speed is reduced to less than 70% of the initial cutting speed between when the workpiece first contacts the wire grid and when the cutting depth is half the diameter of a cylinder, and then increased.

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