Chalcogenide GeTe-Based Non-Volatile Switched K-Band Tunable Reflective Load for Reconfigurable RF Circuits

This paper reports the design and fabrication of a monolithically integrated tunable reflective load. The device is optimized to operate in
$K$
-Band and developed utilizing phase change material (PCM) germanium telluride (GeTe) to gain switching functionality. The proposed device utilizes a disc shaped resonator loaded with switched eight metal-insulator-metal (MIM) monolithic lumped component. The lumped components are monolithically integrated with eight non-volatile PCM radio frequency (RF) series switches in a compact 0.5 mm × 0.5 mm package including the pads of the CPW input port and the control pads. The resonance frequency of various states is pushed beyond 40 GHz to get a resonance-free K-Band (18 GHz to 26.5 GHz) tuning zone. The device is fabricated using an eight-layer in-house optimized microfabrication process. The integrated RF PCM switches exhibit excellent RF performance with measured insertion loss lower than 0.2 dB and isolation better than 30 dB over operational bandwidth. The proposed switched reflective load promises to be useful in developing various reconfigurable RF circuits.