Fully self-aligned power trench-MOSFET utilising 1 /spl mu/m pitch and 0.2 /spl mu/m trench width

Using advanced photolithography and etching techniques, plus an innovative self-aligned process, trench MOSFETs with cell pitches between 1 /spl mu/m and 4 /spl mu/m with a trench width of 0.2 /spl mu/m have been fabricated. The 1 /spl mu/m cell pitch stripe technology achieves a specific (silicon only) on-resistance 10 m/spl Omega/.mm/sup 2/ at a gate voltage of 10 V and with a blocking voltage of 26 V. The trade-off between device on-state resistance and 'Miller' charge was investigated by varying the cell pitch. The 4 /spl mu/m cell pitch stripe technology achieves a figure of merit (Rds[on]/spl times/Q/sub gd/) of 13 m/spl Omega/.nC at a gate voltage of 10 V with a blocking voltage of 27 V.