We are currently developing basic building blocks for creating digital logic units that are based on mechanical components. Transistors, which are semiconductor devices, rely on doping to change intrinsic semiconductor to extrinsic semiconductors. However, at low or high temperatures, that control is impossible as semiconductors revert to intrinsic behaviour. Also, semiconductors exhibit various complications under ionizing (radiation) environment.
We have fabricated logic units using micro-mechanical relays using MEMS technology. The logic units consist of a micro-mechanical relay with three electrical gates. The mechanical relay is fabricated with a cantilever over an airgap, and is operated by applying voltage to the gate. The applied voltage creates an electric force between the gate and a cantilever structure. The electrostatic force arches the cantilever into electrical contact. Since the operation does not depend on controlling the type of charge carriers, the proposed method does not suffer from the limitations shared by semiconductors. With different input combinations applied to the gates of the device, development of MEMS mechanical logic, leading to general digital circuits, is possible. Characterization of the devices is performed, which includes operation times, operation voltages, and maximum
currents. Design, fabrication and testing of these micro-mechanical logic elements will be presented in the paper.