This paper describes the design and characterization of a novel thermal actuator used in a locking switch. Because of the locking mechanism, no energy is needed to stay in the open or closed state. The switch can be used in an automated MEMS-based distribution frame for telecommunication networks. The proposed thermal actuator achieves asymmetric heating by a polysilicon resistor underneath the structural layer, making a high drive resistance while still obtaining a low resistivity signal path in nickel. Making use of a nitride connection, both thermal and electrical isolation is achieved. With a drive resistance of more than 1kohm, displacements up to 70μm are possible at 14V. By placing two of the proposed actuators perpendicular to each other, a locking switch can be obtained. The contacts were plated with gold, resulting in an on-resistance of 0.35ohm. This contact resistance remains below 2ohm, even after 10^5 cycles and a measuring current of 50mA. The breakdown voltage of the switch was measured to be in the range of 450V-600V.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2014: MEMS, Fluidics, Bio Systems, Medical, Computational & Photonics
Published: June 15, 2014
Pages: 25 - 28
Industry sector: Sensors, MEMS, Electronics
Topics: MEMS & NEMS Devices, Modeling & Applications