Characterization of Contact Resistance Stability in MEM Relays With Tungsten Electrodes

The impact of device operating parameters on the ON-state resistance (
R
_ON
) of microelectromechanical relays with tungsten (W) electrodes is reported. Due to the susceptibility of W to oxidation,
R
_ON
increases undesirably over the device operating cycles. This issue is aggravated by Joule heating when the relay is in the on state. The experimental results confirm that shorter ON time, as well as shorter off time, provides for more stable
R
_ON
with respect to the number of ON/OFF switching cycles.