The present disclosure relates to a method and apparatus to increase breakdown voltage of a semiconductor power device. A bonded wafer is formed by bonding a device wafer to a handle wafer with an intermediate oxide layer. The device wafer is thinned substantially from its original thickness. A power device is formed within the device wafer through a semiconductor fabrication process. The handle wafer is patterned to remove section of the handle wafer below the power device, resulting in a breakdown voltage improvement for the power device as well as a uniform electrostatic potential under reverse biasing conditions of the power device, wherein the breakdown voltage is determined. Other methods and structures are also disclosed.
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