In0.53Ga0.47As/AlAs Double-Barrier Resonant Tunnelling Diodes With High-Power Performance in the Low-Terahertz Band

We report about an In0.53Ga0.47As/AlAs doublebarrier resonant tunnelling diode (RTD) epitaxial structure that features high-power capabilities at low-terahertz frequencies (∼ 100−300 GHz). The heterostructure was designed using a TCAD-based quantum transport simulator and experimentally investigated through the fabrication and characterisation of RTD devices. The high-frequency RF power performance of the epitaxial structure was analysed based on the extracted small-signal equivalent circuit parameters. Our analysis shows that a 9 µm², 16 µm², and 25 µm² large RTD device can be expected to deliver around 2 mW, 4 mW, and 6 mW of RF power at 300 GHz.

I. Introduction

RESONANT tunnelling diode (RTD) technology offers a low-power, low-cost, and compact solution suitable to design ultra-broadband wireless transceivers (TRx) for next generation high-speed terahertz (THz) (0.1−10 THz) communications [1]. Although indium phosphide (InP) RTD-based oscillator sources have attained output powers of up to ∼ 1 mW at room temperature (RT) in the 300 GHz-band [2], the unoptimised epitaxial structure of the RTD device is among the main reasons that prevents from meeting the radio frequency (RF) power requirements needed for practical applications.