A 1 million-cell 2.0-m/spl Omega/ 30-V TrenchFET utilizing 32 Mcell/in/sup 2/ density with distributed voltage clamping

A new concept to control TrenchFET avalanche breakdown using an evenly distributed array of voltage clamps in a 1-of-n cell arrangement is introduced, improving on-resistance without sacrificing device ruggedness. Using this technique, a 32 Mcell/in/sup 2/ (5 Mcell/cm/sup 2/) 30-V N-channel TrenchFET with over 1 million active cells is reported having a die resistance of 2.0 m/spl Omega/ and a total packaged on-resistance of 3.1 m/spl Omega/. For V/sub GS/=10 V and a 20-V gate rating, a measured R/sub DS/A of 0.25 m/spl Omega/-cm/sup 2/ is 49% that of a previous-generation 12 Mcell/in/sup 2/ design. Empirically calibrated 3D device simulations illustrate that improved epitaxial current spreading accounts for 31% of the resistance reduction in this density range. TrenchFET avalanche current densities exceeding 950 A/cm/sup 2/ predicted by simulation are confirmed by unclamped inductive switching (UIS) measurements.