July 12, 2011 — CEA-Leti acheived higher reliability in its RF MEMS switch technology via a new design for its electrostatic actuators. The dielectric-less design uses an air gap to prevent contact between the electrodes when the bridge is down, thanks to small dielectric dots placed under the mobile electrode.
Long-term tests show no pull-down voltage drift and significantly increased reliability. By replacing gold with ruthenium for the contacts, CEA-Leti reduced stiction sensitivity and improved device performance. A hermetic thin-film packaging process was developed to prevent organic contamination and lower contact resistance.
The new switch-manufacturing process has been demonstrated on 200mm silicon wafers at the MINATEC dedicated MEMS fabrication platform. Yields close to industrial standards have been achieved, providing thousands of working devices per wafer.
Leti’s industrial partners are currently evaluating samples of these switches for use in efficient reflect-array antennas and redundancy switching matrices for microwave applications.
Leti is an institute of CEA, a French research-and-technology organization with activities in energy, IT, healthcare, defence and security. Leti is focused on nanotechnologies and their applications, mainly NEMS and MEMS. For more information, visit www.leti.fr.