Abstract
In this paper, a drain-engineered double-gate Tunnel-FET (DE-DG-TFET) to enhance the electrical characteristics and analog parameters of a conventional DG-TFET is proposed and examined through calibrated TCAD simulations. Unlike DG-TFET, a constant n-type doping, N-cd, (5 x 10(17) cm(-3) - 2 x 10(18) cm(-3)), in the channel/drain regions of DE-DG-TFET is used, resulting in a p(+)-n-n structure instead of conventional p(+)-i-n structure. Further, p(+)-n-n is modified to p(+)-n-n(+) using electrostatic doping (ED) method on the drain side with Hafnium (phi(m) = 3.9 eV) as a lateral (top and bottom) and side metal electrode. A high n(+)-drain doping ensures the drain contact remains ohmic. Higher electric field at p(+)-n source-channel junction enhances the ON-state BTBT current. While the absence of metallurgical junction provides large tunneling width across the channel/drain junction, resulting in suppression of ambipolar current (I-AMB). At N-cd doping of 1 x 10(18) cm(-3), DE-DG-TFET demonstrates similar to 7 times increase in I-ON while I-AMB is suppressed by similar to 5 orders of magnitude. In addition to this, the proposed device improves analog/RF figures of merit, 45% in voltage gain and similar to 5 times in peak f(T).