Heterostructure Ge-Body pTFETs for Analog/RF Applications

Abstract

This article presents a systematic study on the analog and radio-frequency (RF) performance of type-II staggered heterostructure p-channel tunnel field-effect transistors (pTFETs) with Ge (Germanium) channel and different compound semiconductor source. In order to study the figure-of-merits (FOMs) of analog and RF performances, various Ge-channel pTFETs are designed with Ge, GaAsP, SiGe, and InAlAs sources. The numerical simulation data show an improvement in the FOMs of analog performance such as drain current (Ids), transconductance (gm), transconductance-generation-factor (gm/Ids), and intrinsic gain (gmRo) of the devices with compound semiconductor source compared to Ge-source pTFET devices. Similarly, an improvement in the RF FOMs such as gate-to-source (Cgs) and gate-to-drain (Cgd) capacitances, maximum frequency of oscillation (fMAX), and cutoff frequency (fT) is observed for the devices with GaAsP, SiGe, and InAlAs source compared to Ge-source pTFETs. The simulation results also show that the common-source amplifiers, designed with Ge-heterostructure pTFETs, exhibit a significant enhancement in gain and Gain-Bandwidth product of the circuit.

Keywords

• Tunnel field-effect transistors
• p-type germanium body
• RF/analog performance
• NQS effect
• device simulation