A simple V-shaped microdevice for high-performance, wide-range vacuum and multifunctional sensing applications

This study presents a V-shaped microelectromechanical systems (MEMS) device designed to harness mode localization and nonlinear dynamic effects for high-performance pressure and/or multifunctional sensing. Three V-shaped devices with different geometric configurations were fabricated and tested to evaluate their pressure-sensing performance and anti-crossing behavior under pressure. The latter is particularly beneficial for sensing applications, as it ensures the device remains unaffected by pressure variations, eliminating the need for an additional packaging system. By exploiting mode coupling between the frequencies of symmetric and anti-symmetric modes, the sensors exhibited significant frequency and amplitude shifts across a pressure range of 0.1–760 Torr. One device demonstrated a sensitivity of up to 508.4 ppm/Torr near ambient pressure, while another achieved an ultra-high sensitivity of 7460 ppm/Torr in the medium-vacuum range and 1205.4 ppm/Torr in the low-vacuum range, showcasing excellent sensitivity and linearity. The third device showed a robustness against pressure variations, with one mode selectively insensitive to pressure but responsive to other stimuli, enabling multimodal sensing capabilities. Moreover, the device has been tested under temperature environmental variation, showing a low sensitivity of 20.4 ppm/ 0 C. Comparative analysis with existing MEMS pressure sensors underscores the proposed design's advantages in structural simplicity, compact size, and high sensitivity, particularly in low-vacuum environments, positioning it as a promising solution for advanced sensing applications in biomedical, environmental, and industrial domains. • Introduces a simple V-shaped micro-device demonstrating mode localization and nonlinear dynamics for multifunctional sensing. • Fabricated and tested three geometric configurations to study pressure-sensing performance and anti-crossing behavior. • Demonstrates anti-crossing robustness, eliminating the need for additional packaging against pressure variations. • Achieves ultra-high sensitivity of 7460 ppm/Torr in medium-vacuum, 1205.4 ppm/Torr in low-vacuum, and 508.4 ppm/Torr near ambient pressure and anti-crossing behavior with temperature. • Enables multimodal sensing, with selective modes insensitive to pressure but responsive to other stimuli. • Exhibits structural simplicity, compact design, and superior performance compared to existing pressure micro-sensors. • Offers strong potential for applications in biomedical, environmental, and industrial sensing.