A novel bulk micromachined RF MEMS switch with high isolation and reliability

In this paper, a novel K-band RF MEMS shunt switch fabricated on a high resistivity silicon substrate using Bulk Micro-machined technology is presented. The switch implements a novel concept of tri-layer sandwich (Insulator-Metal-Insulator) membrane which results high isolation (>45 dB) as well as lower actuation voltage of 16 Volt. The switch uses electrostatic actuation mechanism and has measured insertion loss and isolation of 1.51 dB and 47.6 dB at 23.5 GHz respectively. The switching speed of the switch is 78 μsec and repeats the same RF performance after several cycles of operation without deterioration. The switch can have applications in low voltage communication system, phased array radars system etc.