Patent ID: 7201176
Filing Date: 2007-04-10
Classification: H01L

Abstract:
1. A wafer chuck for supporting a wafer during spin process cleaning of edges, bevels, and backsides of a wafer, the wafer chuck comprising: a first plurality of retractable wafer chuck tips to engage the edge of the wafer by extending the first set of retractable wafer chuck tips from the wafer chuck in a direction substantially parallel to the axis of rotation of the wafer chuck; and a second plurality of retractable wafer chuck tips to engage the edge of the wafer by extending the second plurality of retractable wafer chuck tips from the wafer chuck in a direction substantially parallel to the axis of rotation of the wafer chuck, wherein the first and second pluralities of retractable wafer chuck tips are configured so that in a first state the first plurality of retractable wafer chuck tips are engaged with the edge of the wafer and the second plurality of retractable wafer chuck tips are not engaged with the edge of the wafer and wherein in a second state the first plurality of retractable wafer chuck tips are not engaged with the edge of the wafer and the second plurality of retractable wafer chuck tips are engaged with the edge of the wafer.