MEMS RF-SWITCH WITH CONTROLLED CONTACT LANDING

摘要

A MEMS switch contains an RF electrode 102, pull-down electrodes 104 and anchor electrodes 108 located on a substrate 101. A plurality of islands 226 are provided in the pull-down electrode and electrically isolated therefrom. On top of the RF electrode is the RF contact 206 to which the MEMS-bridge 212, 214 forms an ohmic contact in the pulled-down state. The pull-down electrodes 104 are covered with a dielectric layer 202 to avoid a short-circuit between the bridge and the pull-down electrode. Contact stoppers 224 are disposed on the dielectric layer 202 at locations corresponding to the islands 226, and the resulting gap between the bridge and the dielectric layer in the pulled-down state reduces dielectric charging. In alternative embodiments, the contact stoppers are provide within the dielectric layer 202 or disposed on the islands themselves and under the dielectric layer. The switch provides good controllability of the contact resistance of MEMS switches over a wide voltage operating range.