30 nm E-mode InAs PHEMTs for THz and future logic applications

Abstract

We have demonstrated 30 nm E-mode InAs PHEMTs with outstanding Tera-Hz (THz) and logic performance. The devices feature a Pt gate sinking process to effectively thin down the In_0.52Al_0.48As barrier layer. Fabricated devices show excellent L_g scalability down to 30 nm with record f_T in E-mode devices, and record combination of f_T and f_max in any transistor technology. In particular, 30 nm devices exhibit V_T = 80 mV, g_m,max = 1.83 mS/mum, S = 73 mV/dec, DIBL = 85 mV/V, f_T = 601 and f_max = 609 GHz at V_DS = 0.5 V. We have also estimated a source injection velocity of v_inj = 2.5 times 10⁷ cm/s at V_DS = 0.5 V, about a factor of two higher than state-of-the-art Si MOSFETs These encouraging results stem from the outstanding transport properties of InAs as a channel material coupled with well-tempered design features that improve short-channel effects through insulator thickness scaling with buried Pt-gate.