HIGH-BREAKDOWN CHARACTERISTICS OF THE INP-BASED HETEROSTRUCTURE FIELD-EFFECT TRANSISTOR WITH IN0.34AL0.66AS0.85SB0.15 SCHOTTKY LAYER

We report improved breakdown characteristics of InP-based heterostruct ure field-effect transistors (HFET's) utilizing In(0.34)Al(0.66)AS(0.8 5)Sb(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(0.34)Al(0.66)AS(0.85)Sb(0.15) Schottky la yer, 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 breakdow n voltage of 18 V at 300 K for In0.75Ga0.25As channel, are achieved, M oreover, the temperature dependence of two-terminal reverse leakage cu rrent is also investigated. The two-terminal gate-to-drain breakdown v oltage 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 mu m.