Fabrication and characterisation of enhanced barrier AlGaN/GaN HFET

Abstract
An AlGaN/GaN HFET incorporating a piezoelectrically enhanced two-layer barrier structure has been fabricated and characterised. The gate leakage current was observed to be suppressed by one order of magnitude, compared to that in a conventional AlGaN/GaN HFET. Breakdown voltages in the piezoelectrically enhanced and conventional HFET structures are ~100 V and have positive temperature coefficients.