Study on Low-voltage Mechanical Switches With Stiction-recovery Actuation

Abstract

Mechanical switches have the distinct advantages of high isolation, low on-resistance, low power consumption and abrupt switching characteristics; however, their high actuation voltage impedes wider usage. In this work, the problem of the high actuation voltage is solved in two ways. First, a novel electrode design is proposed and fabricated with cantilever-type switches. Introduction of the electrode enabled reduction of the actuation voltage to just 60 % of the level attained with conventional design. Moreover, faster switching and higher level of endurance could be achieved owing to the new electrode design. Second, an ultimate low-voltage torsional switch is proposed adopting stiction-recovery actuation. With advanced hinge design, actuation voltage was reduced to 1.5 V which is far lower than that of other mechanical switches. Moreover, the switch has shown the best performance in view of low-power consumption and reliability among other mechanical switches targeting mechanical logic application. As an example of possible applications, the switch was combined with TFT to comprise MEMS-TFT hybrid inverter and its electrical characteristics were demonstrated.