Non-Linearity Analysis of RF Ohmic Switches Based on Phase Change Materials

We report on a thermoelectric model that can be used to analyze the nonlinearity and power handling capability of RF switches based on phase change (PC) materials. To analyze the nonlinear behavior of the PC switches, the Poole-Frenkel effect, the variation of thermal and electrical conductance with temperature, and the effect of Joule heating with increased RF signal power are all taken into account. The simulated input third-order intercept point and the 1-dB compression point (P
_1dB
) are compared with measured results of directly heated PC switches, showing a good agreement. Using this model, we provide insights into the effect of electrical resistance, and thermal properties, as well as the operation frequency on the switch nonlinearity and power handling capability.