Electrical performance improvement of charge plasma-based junctionless TFET using novel coalescence of SiGe/GaAs and heterogeneous gate dielectric

In this research article, a junctionless tunnel field-effect transistor (JLTFET) based on the charge plasma concept has been proposed and analyzed using novel coalescence of semiconductor materials (Si1-xGex/GaAs) and heterogeneous gate dielectric (SiO2/HfO2). This device utilizes Si1-xGex compound at the source side and GaAs compound at the drain and channel side. The electrical performance of the proposed dual-dielectric material gate heterogeneous JLTFET (DMG-HJLTFET) is compared with the conventional homogeneous-material Si-JLTFET. It is observed that DMG-HJLTFET provides better results in comparison to Si-based JLTFET, with ~ 678 and ~ 3 × 104 times larger ON-state current (ION) and ON-state current/OFF-state current ratio (ION/IOFF) along with ~ 2 × 10–2, 16.66%, and 65% smaller IOFF, threshold voltage (Vth), and subthreshold slope (SS), respectively. The favorable results are obtained due to the formation of a conduction band (C.B) local minima at the source/channel (SE/CL) interface at an ideal Ge mole composition (x = 0.9) in Si1-xGex, which is the reason for the thinner tunneling barrier breadth. Moreover, when compared to Si-JLTFET, the DMG-HJLTFET has 496 times larger transconductance (gm), resulting in ~ 1.4 × 102, 788, and 8 × 102 times higher device efficacy, cut-off frequency (fT), and gain bandwidth product (GBP), respectively, as well as a ~ 40%, lower parasitic capacitance value, making it ideal for fast switching applications.