An ultra dense trench-gated power MOSFET technology using a self-aligned process

An ultra dense trench technology is reported in this paper. This advanced technology employs a fully self-aligned contact process. As a result, the cell pitch of 30 V trench-gated power MOSFETs has been reduced to 1.1 um. The specific on-resistance (including the source metal spreading resistance) of the median die size device has been reduced to 0.18 mohm.cm/sup 2/ at a gate voltage of 10 V. The tradeoffs, which are given towards the optimization of ultra dense trench-gated device's on-resistance, "Miller" charge, and breakdown voltage, are presented.