Electron Velocity Of 6 X 10(7) Cm/S At 300 K In Stress Engineered Inaln/Gan Nano-Channel High-Electron-Mobility Transistors

A stress engineered three dimensional (3D) Triple T-gate (TT-gate) on lattice matched In0.17Al0.83N/GaN nano-channel (NC) Fin-High-Electron-Mobility Transistor (Fin-HEMT) with significantly enhanced device performance was achieved that is promising for high-speed device applications. The Fin-HEMT with 200-nm effective fin-width (W-eff) exhibited a very high I-Dmax of 3940 mA/mm and a highest g(m) of 1417 mS/mm. This dramatic increase of I-D and g(m) in the 3D TT-gate In0.17Al0.83N/GaN NC Fin-HEMT translated to an extracted highest electron velocity (v(e)) of 6.0 x 10(7) cm/s, which is similar to 1.89 x higher than that of the conventional In0.17Al0.83N/GaN HEMT (3.17 x 10(7) cm/s). The v(e) in the conventional III-nitride transistors are typically limited by highly efficient optical-phonon emission. However, the unusually high v(e) at 300 K in the 3D TT-gate In0.17Al0.83N/GaN NC Fin-HEMT is attributed to the increase of in-plane tensile stress component by SiN passivation in the formed NC which is also verified by micro-photoluminescence (0.47 +/- 0.02 GPa) and micro-Raman spectroscopy (0.39 +/- 0.12 GPa) measurements. The ability to reach the v(e) = 6 x 10(7) cm/s at 300 K by a stress engineered 3D TT-gate lattice-matched In0.17Al0.83N/GaN NC Fin-HEMTs shows they are promising for next-generation ultra-scaled highspeed device applications. (C) 2015 AIP Publishing LLC.