High performance GaSb p-channel MODFETs

GaSb p-channel MODFETs based on an AlSbAs-AlSb barrier and GaSb channel have been fabricated and studied. High transconductances and low gate leakage currents have been obtained. Peak transconductances as high as 50 mS/mm at room temperature and in the range of 220-283 mS/mm at 77 K have been achieved. The 77 K peak transconductance for a compound p-channel HFET clearly demonstrates the superior transport properties of holes in GaSb. In addition, gate leakage currents three orders of magnitude lower than the maximum drain saturation current have been achieved at 77 K. Variations in the transconductance characteristics of the devices are also studied and attributed to parallel conduction in the barrier layers.<
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