A 50-V, 0.7-m Omega *cm/sup 2/, vertical-power DMOSFET

A 50-V vertical power MOSFET with extremely low specific on resistance is reported. Devices with a cell density as high as 8 million cells/in/sup 2/ and capable of switching 160 A of current have been successfully fabricated using an improved fabrication technology which used low processing temperatures, double-layer interlevel dielectric, shallow source implants, and an improved source contact metallurgy. The lowest measured specific on resistances are 0.8 and 0.7 m Omega *cm/sup 2/, respectively, under continuous and pulsed bias conditions for FETs capable of blocking 50 V in the reverse direction. This result represents the best ever reported forward conductivity for a 50-V power MOSFET.<
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