Temperature Effects in Packaged RF MEMS Switches with Optimized Gold Electroplating Process

• Published in: Micromachines (Basel) Vol. 15; no. 9; p. 1085
• Main Authors: Wang, Lifeng, Jiang, Lili, Ma, Ning, Huang, Xiaodong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 28.08.2024; MDPI
• Subjects: Bias; Composite materials; Design; Electrodes; Electroplating; Gold; gold electroplating process; Insertion loss; lifetime; Mechanical properties; Microelectromechanical systems; Optimization; Plating; Process parameters; pull-in voltage; Radio frequency; RF MEMS switch; Satellite communications; Surface roughness; Surface stability; Switches; Temperature effects; Thermal stability; Thermodynamic properties; RF MEMS switch; lifetime; temperature effects; pull-in voltage; gold electroplating process
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi15091085

Due to its excellent electrical performance, mechanical reliability, and thermal stability, electroplated gold is still the most commonly used material for movable beams in RF MEMS switches. This paper investigates the influence of process conditions on the quality and growth rate of gold electroplating, and the optimized process parameters for the gold electroplating process are obtained. The characterization of the optimized electroplated gold layer shows that it has small surface roughness and excellent thermal stability. With this optimized gold electroplating process, the RF MEMS switches are fabricated and hermetic packaged. In order to obtain the temperature environment adaptability of the packaged switch, the influence of working temperature is studied. The temperature effects on mechanical performance (includes pull-in voltage and lifetime) and RF performance (includes insertion loss and isolation) are revealed.