Patent ID: 9123582
Filing Date: 2015-09-01
Classification: G01B,H01L

Abstract:
1. A method to measure bow of a wafer within a plasma processing system, the method comprising: transferring the wafer into the plasma processing system; measuring a first plurality of distances from a first sensor to a first surface of the wafer to calculate the bow in the wafer, wherein the wafer is moving relative to the first sensor in a first direction while the first sensor is stationary, the first direction including at least one of a z-direction and a theta-direction, and wherein the first sensor is positioned outside of a set of process modules of the plasma processing system; determining whether the calculated bow of the wafer is within a pre-determined range; based on a determination that the calculated bow of the wafer is within the pre-determined range based on a determination that the calculated bow of the wafer is outside the pre-determined range, removing the wafer from the plasma processing system.