Excimer Laser Three-Dimensional Micromachining Based on Image Projection and the Optical Diffraction Effect

An excimer laser three-dimensional (3D) micromachining system is proposed based on a mask image projection method and the optical diffraction effect. The effects of optical diffraction on the laser machining rate are evaluated using a hole-arrayed mask pattern with various feature sizes and hole-area opening ratios. The practical feasibility of the proposed method is demonstrated by machining conical, trihedral, and pyramidal 3D microstructures on polycarbonate substrates. The proposed method greatly simplifies the photo-mask design and preparation task in traditional excimer laser 3D micromachining systems and provides a powerful technique for achieving large-area 3D microstructures with complex patterns and atypical profiles