4H-SiC MESFET with 2.8 W/mm power density at 1.8 GHz

MESFET's were fabricated using 4H-SiC substrates and epitaxy. The D.C., S-parameter, and output power characteristics of the 0.7 /spl mu/m gate length, 332 /spl mu/m gate width MESFET's were measured. At /spl nu//sub ds/=25 V the current density was about 300 mA/mm and the maximum transconductance was in the range of 38-42 mS/mm. The device had 9.3 dB gain at 5 GHz and f/sub max/=12.9 GHz. At V/sub ds/=54 V the power density was 2.8 W/mm with a power added efficiency=12.7%.<<ETX>>

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