Evaluating Thermal Contact Resistance for Ohmic type RF MEMS switch

Abstract

To understand and control the thermal contact resistance is critical for improving the performance of RF MEMS switch viz., low insertion loss, high isolation as well as low power consumption. This paper presents the design, modeling, and analysis of the RF-MEMS switch for evaluating thermal contact resistance. Thermal contact resistance depends on the thin film materials used, contact force, the roughness factor, material occupying the void spaces, and temperature. The contact force is considered in our analysis for determining the contact resistance. The further one-dimensional heat flow model is used to understand the dynamic behavior of the switch. Finite element analysis software ANSYS is used to obtain modal frequencies, stresses induced in the membrane. The calculations indicate that the total thermal contact resistance of the device is 5.89 k/w. The RF performance parameters are extracted from HFSS software which shows that insertion loss of 0.17dB up to 25 GHz, return loss better than 37dB at 2 GHz and 16dB up to 25 GHz is obtained.