Microswitches with sputtered Au, AuPd, Au-on-AuPt, and AuPtCu alloy electric contacts

This paper is the first to report on a new analytic model for predicting microcontact resistance and the design, fabrication, and testing of microelectromechanical systems (MEMS) metal contact switches with sputtered bimetallic (i.e., gold (Au)-on-Au-platinum (Pt), (Au-on-Au-(6.3at%)Pt)); binary alloy (i.e., Au-palladium (Pd), (Au-(3.7at%)Pd)), and ternary alloy (i.e., Au-Pt-copper (Cu), (Au-(5.0at%)Pt-(0.5at%)Cu)) electric contacts. The microswitches with bimetallic and binary alloy contacts resulted in contact resistance values between 1-2 Omega. Preliminary reliability testing indicates a 3 x increase in switching lifetime when compared to microswitches with sputtered An electric contacts. The ternary alloy exhibited approximately a 6 x increase in switch lifetime with contact resistance values ranging from approximately 0.2-1.8 Omega.