Excimer Laser Micromachining of Three-Dimensional (3D) Microstructures Based on Hole Area Modulation and Optical Diffraction Principle

• Main Authors: Yu-HsuanHung, 洪羽璇
• Other Authors: Yung-Chun Lee
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/93972718672281715090

碩士 === 國立成功大學 === 機械工程學系 === 102 === The purpose of this thesis is to use an excimer laser micromachining system to fabricate 3D microstructures with quite arbitrary profiles. The key point of this method depends on the optical diffraction phenomenon when applying a Hole Area Modulation (HAM) method with an optical image projection system. The advantages of this method are its straightforwardness, easiness in application, low-cost, and most importantly, its capability to produce three-dimensional (3D) microstructures with versatile surface profile. In this thesis, the optical diffraction effect existing in an excimer laser micromachining system will be first studied both theoretically and experimentally. The first goal is to determine quantitatively how the laser machining rate is affected by the optical diffraction of mask patterns with different hole-radius and pitches. Based on this result, several 3D microstructures with different surface profiles are chosen and implemented through photo-mask design and excimer laser machining. The experiment results are compared with simulation data to verify the feasibility, precision, and limitations of this 3D microstructure fabrication method. Using this method, 3D microstructures with complicated profiles can be easily fabricated and the surface roughness is significantly improved. As can be expected, surface profiles containing sharp edges and pointed angles are less applicable by this laser machining method. Otherwise, the machining accuracy can be controlled within 1 μm.