Patent ID: 7579667

Claim:
A bonded-wafer semiconductor device comprising: a semiconductor substrate having first and second main surfaces opposite to each other; a buried oxide layer disposed on at least a portion of the first main surface of the semiconductor substrate; a multi-layer device stack having a first main surface and a second main surface, the multi-layer device stack including: a first device layer of a first conductivity disposed on the buried oxide layer; a second device layer of a second conductivity opposite to the first conductivity disposed on the first device layer; a third device layer of the first conductivity disposed on the second device layer; and a fourth device layer of the second conductivity disposed on the third device layer; at least one trench formed in the first main surface of the multi-layer device stack, the at least one trench extending to a first depth position in the multi-layer device stack; at least one mesa proximate the first main surface of the multi-layer device stack being defined by the at least one trench, the at least one mesa having a first sidewall and a second sidewall opposite the first sidewall; a first anode/cathode layer disposed on a first sidewall of the multi-layer device stack; and a second anode/cathode layer disposed on the second sidewall of the multi-layer device stack.