AlGaN/GaN Round-HEMTs on [111] silicon substrates

AlGaN/GaN Round-HEMTs on silicon substrates have been realised and their static characteristics investigated. The AlGaN/GaN (x=0.23) material structures were grown on [111] p-Si by LP-MOVPE. Devices with 0.3 /spl mu/m gate length exhibit a saturation current of 0.82 A/mm, a good pinch-off and a peak extrinsic transconductance of 110 mS/mm. Highest saturation current reported so far and static output characteristics up to 20 V demonstrate that the devices are capable of handling 16 W/mm of static heat dissipation without any degradation of their performance.