摘要 |
The specification describes a gettering technique for bonded wafers. The handle wafer is provided with a phosphorus predeposition to getter impurities from the handle wafer. The surface to be bonded of the handle wafer is then polished to prepare the wafer for bonding. During polishing the top side phosphorus layer is removed, thereby eliminating the potential for updiffusion of phosphorus from the gettering layer into the device regions of the device layer. The phosphorus gettering layer on the backside of the handle wafer is retained for additional gettering during the bonding operation and during subsequent processing of the device wafer.
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