Advanced composite high-κ gate stack for mixed anion arsenide-antimonide quantum well transistors

This paper demonstrates the integration of a composite high-κ gate stack (3.3 nm Al₂O₃-1.0 nm GaSb) with a mixed anion InAs_0.8Sb_0.2 quantum-well field effect transistor (QWFET). The composite gate stack achieves; (i) EOT of 4.2 nm with <;10^-7A/cm² gate leakage (ii) low D_it interface (~1×10¹² /cm²/eV) (iii) high drift μ of 3,900-5,060 cm²/V-s at N_S of 5×10¹¹-3×10¹²/cm². The InAs_0.8Sb_0.2 MOS-QWFETs with composite gate stack exhibit extrinsic (intrinsic) g_m of 334 (502) μS/μm and drive current of 380 μA/μm at V_DS = 0.5V for Lg=1μm.