MEMS based single device "XOR" and "aND" logic gates for LSI mechanical processors operating in high radiation environments

Abstract

Here we demonstrate the feasibility of MEMS functional devices where a single device functions as a logic gate. This novel approach reduces the number of MEMS devices needed to implement a mechanical processor by ∼10X. MEMS processors are suitable for operation in harsh environment in engines and in the presence of ionizing radiations. Generally, MEMS devices have overall lower speed and less reliability than CMOS. By reducing the number of devices needed for a given operation, our approach improves yield, reproducibility, speed and simplifies implementation of MEMS-based circuits such as adders and multiplexers. Specifically, we discuss XOR & AND gates fabricated on Si3N4 & Polysilicon as bridge materials using W electrodes. The XOR gates with ∼1.5V turn-on voltage at 50MHz with >109 cycles of reliable operations and low operational power consumption (leakage current and power <10-9, <1μW) were tested. We also present data showing the operation of XOR without deterioration at high temperature and in 90kW ionizing radiation for 120 minutes. Related circuits such as 2-bit full adder and multiplexer are also discussed.