High-temperature electrical transport in AlxGa1-xN/GaN modulation doped field-effect transistors

High-temperature electrical transports in AlGaN/GaN modulation doped field-effect transistors (MODFETs) grown by metal organic chemical vapor deposition method have been studied experimentally. The MODFETs have a channel length of 1.5 mu m and a gate width of 40 mu m. The influence of pinchoff voltage, gate voltage, and source-drain voltage on the electrical transports has been addressed. The role of polarization and piezoelectric effect and the fundamental physics underlying leakage have also been elucidated. The maximum drain-source current is 525 mA/mm at a gate bias of 2 V, source-drain bias of 4 V, and temperature of 300 K. The highest room temperature extrinsic transconductance is 155 mS/mm. The breakdown voltage is about 100 V at 28 and 78 degrees C. (c) 2006 American Institute of Physics.