RF MEMS Switch with low stress sensitivity and low actuation voltage

Due to the development of micro-mechanical systems (MEMS), RF MEMS switches are being widely investigated. Although RF MEMS switches have been intensively studied, limited work was done on switches that are suitable for integration in large switching networks such as switch matrices and multi-bit phase shifters. These switching networks require very small switches each with independent controls. Their major existing problems are the high actuation voltage and the low switch yield. High actuation voltage is undesired as a more complicated circuitry is required to provide suitable control signal. Low yield is another drawback as it could result in malfunctioning of some of the switches and thus the entire integrated system. One of the major contributions in resulting of low yield in RF MEMS switches are their dependency to the residual stress of the fabrication process both across one wafer and across batches. This problem is much more pronounced on switches with long length as they deform to their curled shape and prevent switching. In this paper, a novel type of switch is proposed that could reduce the stress sensitivity of the switch as well as providing a low actuation voltage. The overall switch structure is design with size miniaturization.