Tunable oxide-bypassed trench gate MOSFET: breaking the ideal superjunction MOSFET performance line at equal column width

The superjunction (SJ) MOSFET power device is recognized for its higher blocking capability and lower on-state resistance that break the conventional unipolar silicon limit. However, SJ devices below 100 V rating incur the constraint of unrealistically narrow column widths , and their performance is greatly handicapped due to difficulties in the formation of perfectly charge-balanced SJ p-n columns by current process technology. Based on an alternative approach of the tunable oxide-bypassed (TOB) SJ MOSFET concept, a TOB-UMOS device of 79 V rating has been successfully fabricated for the first time. Laboratory measurements indicate that the device breaks the ideal SJ MOSFET performance line at equal column width of 3.5 μm, and potentially the ideal silicon limit as well.