Barrier-Engineered Arsenide–Antimonide Heterojunction Tunnel FETs With Enhanced Drive Current

In this letter, we experimentally demonstrate enhancement in drive currentIONand reduction in drain-induced barrier thinning (DIBT) in arsenide-antimonide staggered-gap heterojunction (hetj) tunnel field-effect transistors (TFETs) by engineering the effective tunneling barrier height Ebefffrom 0.58 to 0.25 eV. Moderate-stagger GaAs0.4Sb0.6/In0.65Ga0.35As (Ebeff= 0.31 eV) and high-stagger GaAs0.35Sb0.65/In0.7Ga0.3As (Ebeff= 0.25 eV) hetj TFETs are fabricated, and their electrical results are compared with the In0.7Ga0.3As homojunction (homj) TFET (Ebeff= 0.58 eV). Due to the 57% reduction in Ebeff, the GaAs0.35Sb0.65/In0.7Ga0.3As hetj TFET achieves 253% enhancement inIONover the In0.7Ga0.3As homj TFET atVDS= 0.5 V andVGS-VOFF= 1.5 V. With electrical oxide thickness (Toxe) scaling from 2.3 to 2 nm, the enhancement further increases to 350 %, resulting in a record highIONof 135 μA/μm and 65% reduction in DIBT atVDS= 0.5 V.