DUAL-SURFACE POLISHING DEVICE

摘要

Disclosed is a dual-surface polishing device which has at least: upper and lower setting plates which have polishing cloths attached thereto; a carrier which has a holding-hole formed therein to hold a wafer between the upper and lower setting plates; a sensor which is disposed in a through-hole provided in the direction of the rotation axis of the upper setting plate, and detects the thickness of the wafer being polished; and a sensor holder for holding the sensor, wherein the material used for the sensor holder is quartz. A dual-surface polishing device is therefore provided which can polish a wafer with fewer errors in the target thickness of the wafer by reliably suppressing deformation in the sensor holder caused by the effect of heat produced when the wafer is being polished.