Monolithic PCM Based Miniaturized T-Type RF Switch for Millimeter Wave Redundancy Switch Matrix Applications

This paper presents a novel approach to monolithically implement RF phase change material (PCM) germanium telluride (GeTe) T-type switch for millimeter-wave switch matrix applications. The miniature T-type switch demonstrates three states of operation including one cross-over state and two turn-states. A six-layer micro-fabrication process is developed to fabricate the T-type switch. PCM RF series switches are used to route the signal through various RF sections including 90-degree bends and a cross-over junction. The measured results for the proposed T-type switches demonstrate excellent RF performance of less than 0.6 dB insertion loss, better than 20 dB return loss and higher than 20 dB isolation in all states from DC to 67 GHz. To the best of our knowledge, this is the first implementation of PCM based T-type switch ever reported.