Abstract: A wafer polishing apparatus includes one or more wafer carriers each containing one or more wafers mounted on both sides of the carrier. Upper and lower turntables having upper and lower polishing surfaces, rotate to polish the wafers attached to the carriers. Hence, wafers on the top of the carriers, and wafers on the bottom of the carriers are polished simultaneously. This configuration increases throughput; also, thermal deformations in the wafers are reduced, thus improving flatness.

Abstract: A system and method for reducing kerf loss and controlling the tension and lateral vibration of an internal diameter saw blade by controlling the temperature of the blade while it is still rotating. The blade temperature is controlled by regulating the temperature of the cutting fluid flow associated therewith. In one embodiment blade tension is periodically measured and, when the tension falls below a predetermined limit, the temperature of the cutting fluid stream is decreased for a period of time until the tension increases to a preselected value.

Abstract: A system for measuring the flexure of a saw blade in situ includes in one embodiment a non-contact displacement sensor and means for directing a fluid flow at the blade adjacent the sensor. The deflection of the blade by the fluid flow is detected by the sensor which generates a signal related to blade flexure. The system indicates when a saw blade is correctly tensioned or when retensioning is required.