Method for reclaiming substrate from semiconductor wafers
AssigneeKobe Precision Inc.
InventorJohn E. Lawrence
Life of this patent
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Abstract
A method of reclaiming a substrate wafer and a reclaimed substrate wafer. A semiconductor wafer having external layers from previous processing is reclaimed by etching the external layers and cup-wheel grinding an active surface of the wafer to remove semiconductor components such as diffused regions. Either the active surface or the backside of the wafer is then polished to a mirror finish to provide a highly crystalline surface. The cup-wheel grinding produces a pinwheel surface roughness pattern and is accomplished by grinding the wafer with a cup-shaped grinding wheel having an axis of rotation parallel to but offset from an axis of rotation of the wafer. Preferably, the rim of the cup-shaped grinding wheel always passes over the axis of rotation of the wafer.
Claims23
A process for preparing a reclaimed substrate wafer from a semiconductor wafer, wherein said semiconductor wafer comprises a substrate wafer having an active surface, an opposite passive surface and one or more external layers, wherein said active surface has located therein one or more semiconductor components and wherein said external layers are located on at least one of the active surface and the passive surface, said process comprising the steps of:
- removing said external layers from said substrate wafer;
- subsequent to said removing step, cup-wheel grinding the active surface to remove said semiconductor components and provide a ground surface;
- polishing at least one of said passive and said ground surface.
Dependencies are inferred from the claim text.