Resistance Ratio Enhancement in Chalcogenide Phase-Change RF Switches at Cryogenic Temperatures

This paper reports the DC and RF performance of chalcogenide phase-change RF switches as a function of temperature. Resistance change behavior of the phase-change series switch is investigated over 77 K to 335 K. The device shows metallic behavior in crystalline state which exhibits consistent low resistivity over a wide temperature range, while in amorphous state resistance increases more than eleven-orders of magnitude as a function of decreasing temperature from 300 K to 77 K. At cryogenic temperatures, the device resistance is achieved with exceptionally high amorphous to crystalline state resistance ratio. Device IV characteristics and RF performance are investigated for multiple device cycles. The RF performance of device with and without micro-heater are examined to confirm the performance variation of the phase-change switches at cryogenic temperatures.