Monolithic MEMS SoC Design and Fabrication Using 0.35 μm BCD Technology

In this paper, we provide monolithic MEMS SoC design examples by adopting high-end standard foundry processes, which would be mostly important for speeding up developments on many MEMS system applications. We have demonstrated array-type structure designs, with sensing circuit includes modulation, amplification, and filtering functions, are fabricated monolithically in a 0.35 μm Bipolar/CMOS/DMOS (BCD) 4 metal (with top-metal is 3 μm in these cases) technology. By 6:1 BOE etching, in-plane and out-of-plane moving parts without stress-induced warpage are revealed. Single structure cell could be driven up to 1 MHz, and related simulation and measurement characteristics are also shown. This novel technology has potential to drive up to 60V for most MEMS devices, and fulfills monolithic MEMS SoCs