Progressive Development of Superjunction Power MOSFET Devices

The originally proposed superjunction (SJ) power MOSFET structure with interdigitated p-n columns is highly recognized for its higher voltage-blocking capability and lower specific on -state resistance. However, in practice, the performance of SJ devices is greatly handicapped due to difficulties in the formation of perfect charge-balanced p-n columns by the limitation of fabrication process technology, particularly, for devices with small p-n column widths at low voltage ratings. Recently developed structures of polysilicon-flanked and oxide-bypassed SJ MOSFETs are to overcome the conventional SJ device fabrication limitation. The follow-up development on extending the scope of these recently reported device structures to lateral SJ structures, which is suitable for SJ power integrated circuits, is reported for the first time. In this paper, detailed descriptions of the progressive development and the technical advancement of several SJ MOSFET structures are presented with both simulation and experimental results.