Nd:YAG Laser 직접 각인을 이용한 Carbon 스트레인 센서

Nd:YAG laser was used to carbonize polyimide films to produce carbon films. This is a simple manufacturing process to fabricate low cost sensors. By applying this method, we studied characteristics of flexible and low-cost piezoresistive. Previously, many studies focused on carbonization of polyimide using CO2 laser with wavelength of 10.6 μm. In this paper, carbonization (carbonization process) was performed on polyimide films using an Nd:YAG laser with a wavelength of 1.064 μm. In order to increase the resolution, we optimized the laser conditions of the power density (W/cm2) and the beam scan rate. In previous studies using CO2 laser, the minimum line width was 140~220 μm but in this study, carbon line width was reduced to 35~40 μm. The initial sheet resistance of the carbon sensor was 100~300 Ω/ □. The resistance decreased by 30% under stretched with a curvature radius of 21 R. The calculated gauge factor was 56.6. This work offers a simple, highly flexible, and low-cost process to fabricate piezoresistive sensors.