Scalable Non-Volatile Chalcogenide Phase Change GeTe-Based Monolithically Integrated mmWave Crossbar Switch Matrix

This paper reports a novel millimeter-wave (mmWave) non-volatile chalcogenide phase change material (PCM) germanium telluride (GeTe) based scalable crossbar switch matrix. The proposed 2 ×2 crossbar switch matrix configuration is designed using PCM single-pole double-throw (SP2T) switches monolithically integrated with a scalable crossbar unit-cell. The presented switch matrix utilizes a maximum of only two series PCM switches in any possible signal route, minimizing the insertion loss. The non-volatile PCM switches consume no static dc power. The proposed switch matrix is fabricated in-house using an eight-layer custom micro-fabrication process. The 2 ×2 switch matrix is ultra-compact with the device area under 0.1 mm
²
. Over dc to 40 GHz, the fully integrated 2 ×2 switch matrix exhibits a measured insertion loss less than 1.35 dB, a return loss better than 20 dB, and an isolation higher than 24 dB. The integrated PCM switches utilized in this matrix offer up to +35.5 dBm CW RF power handling and better than +41 dBm of linearity. The RF PCM switches are experimentally tested for more than 1 million reliable switch actuation cycles.