Reliability of RF MEMS switches at cryogenic (liquid He) temperatures

Abstract

This paper reports on the reliability of RF MEMS switches operating in a cryogenic (<6 K) environment while monitoring the repeatability of their contact resistance (Rc) over time. Series DC-contact switches were actuated with a bipolar waveform then checked for stiction every 100 thousand contacts, and after every million cycles Rc was measured 100 times. Device lifetimes were limited to under 10 million contacts. The dominant failure mechanism is believed to be charging of the substrate underneath the electrostatic MEMS switch leading to permanent hold down of the device.