RF switches using phase change materials

Phase change materials are attractive candidates for use in ohmic switches as they can be thermally transitioned between amorphous and crystalline states, showing several orders of magnitude change in resistivity. Phase change switches are fast, small form factor, and can be readily integrated with MEMS and CMOS electronics. As such, they have a great potential for implementing next-generation high-speed reconfigurable RF modules. In this paper, we report on the RF properties of germanium tellurium, a PC material, and its use in RF switching applications. Intrinsic resistance and capacitance at the ON (crystalline) and OFF (amorphous) states of a directly heated switch are compared and characterized. Other properties such as phase transition conditions, insertion loss, return loss, and power handling capability of the switch are also measured and analyzed.