Patent ID: 6759341
Filing Date: 2004-07-06
Classification: H01L

Abstract:
A wafering method comprising:holding a semiconductor wafer in a holder, wherein the wafer has a first surface facing a body of the holder and a second surface opposite to the first surface, and the holder emits gas from the body towards the first surface of the wafer to draw the wafer towards the body, wherein at least some of the gas is allowed to pass around the wafer's edge towards the second surface; with the wafer in the holder, exposing the second surface of the wafer to a substance comprising a plasma in a wafering process, the substance etching the second surface; wherein the second surface comprises a peripheral area adjacent to the wafer's edge and also comprises an area spaced from the wafer's edge; and the peripheral area is etched slower than the area spaced from the wafer's edge.