Toward 120 dB CMOS-MEMS Arrayed Accelerometers Measuring Through k<i>g</i> Shock Events

This paper reports on the development of a monolithic capacitive accelerometer array system that has a designed full-scale range of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pm 5~{\mathrm {\text {k}{g} }}$ </tex-math></inline-formula>, a bandwidth larger than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10~{\mathrm {\text {k}\text {Hz} }}$ </tex-math></inline-formula>, with a minimum resolution of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mathrm {5~\text {m}{g} }$ </tex-math></inline-formula> and a minimum bias instability of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mathrm {700~\mu {g} }$ </tex-math></inline-formula>. The resolution and full-scale range of the accelerometers correspond to a dynamic range of 120 dB that is on par with state-of-the-art low-<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mathrm {{g} }$ </tex-math></inline-formula> accelerometers. High bandwidth and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mathrm {\text {k}{g} }$ </tex-math></inline-formula> detectability are achieved by the nano-gram proof mass and relatively stiff folded-flexure transducer design. High dynamic range with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mathrm {\text {k}{g} }$ </tex-math></inline-formula> input range is enabled by the hourglass-beam, interdigitated tapered comb-finger electrodes, and arrayed accelerometers. The accelerometer array design provides a potential path towards an emerging navigation through high-shock application.[2024-0091]