Investigation of the Electrical Parameters in a Partially Extended Ge-Source Double-Gate Tunnel Field-Effect Transistor (DG-TFET)

A partially extended germanium-source double-gate tunnel field-effect transistor (PEGeDG-TFET) utilizes line and point tunneling phenomena to achieve low ambipolar current and high ON-state current. These advantages are accompanied by an exceptionally low OFF-state current (IOFF) and subthreshold swing with resilience against short-channel effects. However, PEGeDG-TFETs face challenges in terms of large variations in IOFF and changes in electrical characteristics with temperature due to the change in the bandgap of semiconductor material. In this article, we explore the temperature-associated variations of a PEGeDG-TFET under the influence of interface trap charges (ITCs) for reliability assessment. Results revealed that the Shockley-Read-Hall phenomenon is dominant at lower gate bias voltage, leading to IOFF degeneration at high temperature. The band-to-band tunneling (BTBT) phenomenon experiences minor variations at higher temperature and gate voltage. Additionally, at high temperature (500 K), it is discovered that the threshold voltage, cut-off frequency, gain-bandwidth product, transconductance-frequency product, intrinsic gain, and transit time decrease, thus limiting the device reliability in the avionics sector where temperatures fall below 410 K with consistent performance of analog/radio-frequency (RF) parameters. This investigation was conducted via simulations on a Silvaco ATLAS simulator considering ITCs and temperature variations.