Analysis of a Novel Metal Implant Junctionless Tunnel FET for Better DC and Analog/RF Electrostatic Parameters

Steep rise in the subthreshold slope, high current driving capability, and negligible ambipolarity are the major prerequisite conditions of tunnel FETs (TFETs) to make it applicable for Analog/RF circuit applications. Along with that, fabrication of physically doped TFETs is a major concern in device technology. In this context, this paper deals with junctionless TFET with a metal implanted in the oxide at the source/channel and drain/channel junctions to enhance its ON-current and reduce the ambipolar nature. The metal introduced at the source/channel junction generates abruptness and brings improvement in subthreshold slope, which increases the current driving capability of the device. Similarly, the metal implanted at the drain/channel junction widens the energy gap at the same junction to reduce the ambipolar behavior of the device. This also contributes to the enhancement of dc and analog/RF performance of the device. The selection of appropriate work function and length of the metal implanted at both the interfaces is important to maintain the improved ON-current and ambipolarity. This optimization gives idea of keeping the appropriate length, which provides direction toward practical feasibility at the experimental level.