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

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<sub>0.52</sub>Al<sub>0.48</sub>As barrier layer. Fabricated devices show excellent L<sub>g</sub> scalability down to 30 nm with record f<sub>T</sub> in E-mode devices, and record combination of f<sub>T</sub> and f<sub>max</sub> in any transistor technology. In particular, 30 nm devices exhibit V<sub>T</sub> = 80 mV, g<sub>m,max</sub> = 1.83 mS/mum, S = 73 mV/dec, DIBL = 85 mV/V, f<sub>T</sub> = 601 and f<sub>max</sub> = 609 GHz at V<sub>DS</sub> = 0.5 V. We have also estimated a source injection velocity of v<sub>inj</sub> = 2.5 times 10<sup>7</sup> cm/s at V<sub>DS</sub> = 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.