| Radio frequency (RF) microelectromechanical systems (MEMS) switches are paramount in importance for improving current and enabling future USAF RF systems. Electrostatic micro-switches are ideal for RF applications because of their superior performance and low power consumption. The primary failure mechanisms for micro-switches with gold contacts are becoming stuck closed and increased contact resistance with increasing switch cycles. This dissertation reports on the design, fabrication, and testing of micro-switches with sputtered bimetallic (i.e., gold (Au)-on-Au-(6.3at%)platinum (Pt)), binary alloy (i.e., Au-(3.7at%)palladium (Pd) and Au-(6.3at%)Pt), and ternary alloy (i.e., Au-(5at%)Pt-(0.5at%)copper (Cu)) contact metals. Performance was evaluated, in-part, using measured contact resistance and lifetime results. The micro-switches with bi-metallic and binary alloy contacts exhibited contact resistance between 1--2 ohms and, when compared to micro-switches with sputtered gold contacts, showed an increase in lifetime. The micro-switches with tertiary alloy contacts showed contact resistance between 0.2--1.8---and also showed increased lifetime. Overall, the results presented in this dissertation indicate that micro-switches with gold alloy electric contacts exhibit increased lifetimes in exchange for a small increase in contact resistance. |
