Experimental Investigation of Performance, Reliability, and Cycle Endurance of Nonvolatile DC–67 GHz Phase-Change RF Switches

Abstract

This article reports high-performance and reliable phase change material (PCM) germanium telluride (GeTe)-based nonvolatile radio frequency (RF) switches. The highly miniaturized ultrawideband dc to 67 GHz millimeter-wave (mmWave) switches is developed in-house using a custom eight-layer microfabrication process. The switches are fully passivated and do not require any special packaging for integrating heterogeneously with other technologies. They are also amenable to monolithic integration with a wide range of RF devices on a single chip, such as phase shifters, impedance tuners, and attenuators, to name a few. The PCM GeTe-based RF switches are experimentally tested for their RF performance variation across the wafer, performance change at high temperature, high-power handling capability, third-order intercept (TOI) through the two-tone testing setup, and switching speed. The nonvolatile resistance state reliability of the PCM switches is experimentally investigated. The presented RF switches are cycled more than one million times, demonstrating reliable actuation operation with a figure of merit exceeding 14.5 THz. A detailed description of the experimental setup for measuring the switching speed, power handling capability, linearity, reliability, and cycle endurance assessment of the PCM switches is presented. The PCM switches developed are compared with the current state-of-the-art demonstrating a clear improvement in various aspects of the switch’s performance.