Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Contact voltage-induced softening of RF microelectromechanical system gold-on-gold contacts at cryogenic temperatures

Journal Article · · Journal of Applied Physics
DOI:https://doi.org/10.1063/1.3459893· OSTI ID:21476432
;  [1];  [2]
  1. Department of Physics, North Carolina State University, Raleigh, North Carolina 26795 (United States)
  2. Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 26795 (United States)

A series of experiments were performed in vacuum environments to investigate the impact of rf micromechanical system switch contact voltage versus resistance for gold-on-gold contacts at cryogenic temperatures. The purpose of this work was twofold as follows: (1) to examine whether asperity heating models already validated for high temperature contacts were also applicable at cryogenic temperatures and (2) to explore the implications and validity of prior suggestions that contact temperatures between 338 and 373 K are high enough to dissociate adsorbed film and/or push them aside but low enough to prevent asperities from becoming soft and adherent. Measurements on two distinct switch types, fabricated at independent laboratories, were performed in the temperature range 79-293 K and for contact voltages ranging from 0.01 to 0.13 V. Contact resistance values at all temperatures were observed to be lower for higher contact voltages, consistent with the aforementioned asperity heating models, whereby increased contact currents are associated with increased heating and softening effects. In situ removal of adsorbed species by oxygen plasma cleaning resulted in switch adhesive failure. Switches that had not been cleaned meanwhile exhibited distinct reductions in resistance at contact temperatures close to 338 K, consistent with suggestions that films begin to desorb, disassociate, and/or be pushed aside at that temperature.

OSTI ID:
21476432
Journal Information:
Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 4 Vol. 108; ISSN JAPIAU; ISSN 0021-8979
Country of Publication:
United States
Language:
English