An 1800 V triple implanted vertical 6H-SiC MOSFET

6H silicon carbide vertical power MOSFETs with a blocking voltage of 1800 V have been fabricated. Applying a novel processing scheme, n/sup +/ source regions, p-base regions and p-wells have been fabricated by three different ion implantation steps. Our SiC triple ion implanted MOSFETs have a lateral channel and a planar polysilicon gate electrode. The 1800 V blocking voltage of the devices is due to the avalanche breakdown of the reverse diode. The reverse current density is well below 200 /spl mu/A/cm/sup 2/ for drain source voltages up to 90% of the breakdown voltage. The MOSFETs are normally off showing a threshold voltage of 2.7 V. The active area of 0.48 mm/sup 2/ delivers a forward drain current of 0.3 A at Y/sub GS/=10 V and V/sub DS/=8 V. The specific on resistance was determined to 82 m/spl Omega/dcm/sup 2/ at 50 mV drain source voltage and at V/sub GS/=10 V which corresponds to an uppermost acceptable oxide field strength of about 2.7 MV/cm. This specific on resistance is an order of magnitude lower than silicon DMOSFET's of the same blocking capability could offer.