High-breakdown characteristics of the InP-based heterostructure field-effect transistor with In/sub 0.34/Al/sub 0.66/As/sub 0.85/Sb/sub 0.15/ Schottky layer

We report improved breakdown characteristics of InP-based heterostructure field-effect transistors (HFET´s) utilizing In/sub 0.34/Al/sub 0.66/As/sub 0.85/Sb/sub 0.15/ Schottky layer grown by low-pressure metalorganic chemical vapor deposition. Due to high energy bandgap and high Schottky barrier height (>0.73 eV) of the In/sub 0.34/Al/sub 0.66/As/sub 0.85/Sb/sub 0.15/ Schottky layer, high two-terminal gate-to-drain breakdown voltage of 40 V, three-terminal off-state breakdown voltage of 40 V three-terminal threshold-state breakdown voltage of 31 V, and three-terminal on-state breakdown voltage of 18 V at 300 K for In/sub 0.75/Ga/sub 0.25/As channel, are achieved. Moreover, the temperature dependence of two-terminal reverse leakage current is also investigated. The two-terminal gate-to-drain breakdown voltage is up to 36 V at 420 K. A maximum extrinsic transconductance of 216 mS/mm is obtained with a gate length of 1.5 μm.