Cycling reliability of RF-MEMS switches with Gold-Platinum multilayers as contact material

Contact resistance is the main parameter used for assessing the high cycling reliability of RF microelectromechanical (RF-MEMS) switches. In this paper the use of a modified contact material is tested and compared to pure gold in cycling experiments performed on a RF-MEMS switch in shunt capacitive configuration. The modified contact material is a gold-based multilayer with a thin layer of platinum sandwiched between two layers of gold. The experiment consists in comparing devices with the same layout but with different contact material. While the two types of switch start with similar RF performances, the device with the modified material shows a marked improvement in cycling reliability and a lower series resistance up to 10 cycles when compared to gold contact devices.