Sumit Majumder

An electrostatically actuated broadband ohmic microswitch has been developed for RF and microwave applications. The switch is a three-terminal device based on a cantilever beam and is fabricated using an all-metal, surface-micromachining process. It operates in a hermetic environment obtained through a glass frit wafer-bonding process. RF lifetimes greater than 1010 cycles have been achieved for the wafer capped switch. Typical insertion loss and isolation for a 2-contact switch at 10 GHz are 0.4 and 20 dB, respectively, while the 8-contact switch yields an insertion loss and isolation of 0.2 dB and 27 dB at 2 GHz, respectively. © 2004 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14: 338–344, 2004.

Electrostatically actuated micromechanical switches have been reported in earlier work by the authors. In the present work, a simple contact resistance model of the microswitch is discussed. Preliminary contact resistance measurements are presented, and compared with the modeled contact resistance characteristics

Electrostatically actuated microswitches and relays have been developed at Northeastern University and Analog Devices, Inc. Here, we report a steady-state thermal-electrical finite element model of microswitches with gold-gold contacts. The modeling results show that in a microswitch with a typical geometry, the thermal constriction occurs in the thin film trace leading up to the contact, and not at the contact interface. The model correctly predicts the switch voltage at which the drain trace melts, but underestimates the switch resistance, and therefore overestimates the failure current. SEM images indicate that the contact area increases significantly with current.

Microelectromechanical system (MEMS) microswitches are receiving increasing attention, particularly in the RF community. Low power consumption, low insertion loss, high isolation, excellent linearity, and the ability to be integrated with other electronics all make microswitches an attractive alternative to other mechanical and solid-state switches. This article features a newly developed, surface micromachined, electrostatically actuated direct metal-to-metal microswitch which can be used in applications from dc through microwave.

... 6, NO. 1, MARCH 1997 3 Micromechanical Switches Fabricated Using Nickel Surface Micromachining Paul M. Zavracky, Sumit Majumder, and Nicol E. McGruer ... However, what is most attractive is that the microrelay can be integrated with other devices on a single die. ...

ABSTRACT Micromechanical switches and relays realized by a simple surface micromachining process are presented. The devices use a nickel cantilever beam and gold-to-gold electrical contact, and are electrostatically actuated. They have lifetimes exceeding 109 cycles, and a current handling capability of 150 mA. © 1997 American Vacuum Society.