Circuit Modeling of Tunneling Real-Space Transfer Transistors: Toward Terahertz Frequency Operation

TL;DR

This paper models tunneling real-space transfer transistors (TRSTT) to evaluate their high-frequency performance, showing potential for terahertz operation through circuit simulations aligned with experimental data.

Contribution

It introduces a small signal equivalent circuit model for TRSTT including tunneling effects, enabling accurate prediction of their frequency limits and guiding design optimization for terahertz applications.

Findings

fT in NDR region approaches terahertz range

Model agrees well with experimental data

Resistance of delta-doped layer limits performance

Abstract

High frequency operation of tunneling real-space transfer transistor (TRSTT) in the negative differential resistance (NDR) regime is assessed by calculating the device common source unity current gain frequency (fT) range with a small signal equivalent circuit model including tunneling. Our circuit model is based on an In0.2Ga0.8As and delta-doped GaAs dual channel structure with various gate lengths. The calculated TRSTT fT agrees very well with experimental data, limiting factor being the resistance of the delta-doped GaAs layer. By optimizing the gate dimensions and channel materials, we find fT in the NDR region approaches terahertz range, which anticipates potential use of TRSTT as terahertz sources.