Electron mobility in thin In0.53Ga0.47As channel

Channel thickness Tch dependence of electron mobility μκρρ in thin In<inf>0.53</inf>Ga<inf>0.47</inf>As channels was investigated at temperatures T from 35 to 300 K using conventional parametric and pulsed I<inf>D</inf>-measurements, including a novel technique with time resolution down to 10 ns. It is show that accurate mobility measurements can be obtained using low T and/or fast pulsed measurements, thus avoiding significant underestimations of μκρρ due to charge trapping with slow/parametric measurements. Furthermore, annealing is demonstrated to strongly suppress charge trapping, which results in μ<inf>κρρ</inf> = 1015 cm²/Vs at T<inf>ch</inf> = 7.1 nm, carrier density Ns = 3 × 10¹² cm⁻², and T = 300 K. We demonstrate that room-temperature μκρρ degrades by less than 10% as T<inf>ch</inf> is scaled from 300 nm down to 7 nm, thus indicating that there is no “mobility bottleneck” down to T<inf>ch</inf> = 7 nm.