3D-Ordered Multilevel Microstructures-Based Flexible Pressure Sensor with Ultra-High Sensitivity Utilizing Laser Scribing

This paper describes a piezoresistive flexible pressure sensor based on multilevel microstructure, fabricated through infrared picosecond laser technology. Our systematic study of the impact of laser processing parameters on microstructure morphology led to the creation of single-level, double-level, and triple-level 3D-ordered microstructure-based sensors. Experimental results demonstrate that the triple-level microstructure sensor exhibits an ultra-high sensitivity of 138.6 kP$\mathrm{a}^{-1}$ and a wide linear range of 400 kPa, surpassing the sensitivity of the single-level sensor of 10.5 kP$\mathrm{a}^{-1}$ by 1300%. Moreover, it also surpasses single-level and double-level microstructure-based sensors in terms of measurement range and linearity. Finite element analysis confirms that the sensor based on the triple-level microstructure is more sensitive than sensors based on single-level and double-level microstructures. The proposed method for tailoring microstructure morphology has significant potential for developing pressure sensors with high sensitivity and wide linear range.