Phase Change Material (PCM) Technology for Microwave and mm-Wave Applications

Microwave and mm-wave switches are key components in communication systems. They are used for signal routing and for realizing a wide range of reconfigurable microwave and mm-wave devices. Phase Change Materials (PCM) have been widely used in optical storage media and non-volatile memory devices applications. Over the past recent years, there have been interest in exploiting the PCM materials such as germanium telluride (GeTe) and metal insulator transition materials such as vanadium oxides (VO2) for RF applications. The principle of operation of PCM RF switches is based on the ability of the material to transform from a high-resistivity state (amorphous phase) to low-resistivity state (crystalline phase) and vice versa with the application of short duration pulses. Several orders of resistivity change can be achieved by PCM technology allowing the realization of highly miniature microwave and mm-wave switches. In addition to miniaturization, GeTe based switches offer latching functionality and ease of monolithic integration with other RF circuits. This talk will address recent developments in PCM-switches capable of operating up to 67GHz, and their applications to the realizations of switch matrices, phase shifters, tunable filters, variable attenuators and tunable matching networks.