Performance measurements and non-linearity modeling of GeTe phase change RF switches with direct and indirect heating schemes

In this paper, we report on the design, fabrication, and measured results of phase change RF switches using germanium telluride (GeTe) with two different heating schemes: direct heating and indirect heating. Both switches are fabricated in-house showing insertion loss less than 0.6 dB and isolation above 13 dB at frequencies from DC up to 20 GHz, indicating good RF performance. In order to better analyze the thermal and power handling performance of phase change switches, a thermoelectric model is developed. This model utilizes conclusions from existing efforts, including the Poole-Frenkel (PF) model, but is modified to achieve better agreement with the measurement results. Such accurate thermoelectric modeling method can be used to provide design guidelines for implementing phase change switches with improved performance.