A fast liquid-metal droplet switch using EWOD

A novel liquid-metal (LM) droplet switch is presented, which addresses the switching speed limitation of previously reported LM switches. An actuation technique based on electrowetting-ondielectric (EWOD) gives contact line speeds of 50 cm/s. High accuracy positioning by placing the droplet inside a micro-frame allows us to fabricate devices with switching gaps as small as ˜10 μm. We report switches with switch-on latency of 60 μs and switch-off latency of 150 μs. The rise and fall time for the switched signal was measured to be below 5 μs. In preliminary tests, 1 W of power was hotswitched for 10’s of cycles without any visual degradation. Combining with the RF performance results and the inherent contact reliability of LM, we are developing microswitches for RF applications.