Piezoelectric RF MEMS Switches on Si-on-Sapphire Substrates

Abstract

This paper reports the development of piezoelectrically actuated radio frequency (RF) micro-electromechanical systems (MEMS) switches on Si-on-sapphire substrates using a novel greyscale lithography fabrication technique. Lead zirconium titanate (PZT) thin-film actuators are used to close a series ohmic contact single-pole single-throw (SPST) switch implemented in co-planar waveguide (CPW). The switch design on a Si substrate has maximum insertion loss of 2.6 dB from DC - 67 GHz. While over the same frequency span, the switch on a sapphire substrate exhibits insertion loss better than 1.4 dB and isolation better than 15 dB.