Analysis of tunneling field-effect transistor with germanium source junction using small-signal equivalent circuit

In this study, germanium is used as the source junction material in a tunneling field-effect transistor (TFET) and the Ge-source TFET is analyzed in the perspectives of high-frequency performances. For analyses on the high-frequency parameters, a small-signal equivalent circuit with high credibility and device simulation are operated in cooperation. The errors in capacitances and transconductances, from both approaches, are within 10% up to the terahertz regime. It is found that the Ge-source TFET has smaller gate-to-drain capacitance and tunneling resistance than Si-source device. These features merit make Ge-source TFET more suitable to wide variety of high-speed and low-power applications.