A maskless lithography system is developed which can generate any arbitrary patterns. The system consists of an illumination system, a digital micro mirrors devices (DMD), and a projection system including an achromatic lens pair and a double-sided micro lens and spatial filter array (D-MSFA). The DMD plays as a virtual mask, which can generate any arbitrary patterns by individually turning on or off each micro mirror. The achromatic lens pair projects image of each DMD’s mirror onto the first lens of D-MSFA. The D-MSFA consists of 2 micro lens arrays and a pinholes array which is located at the focal plane of the first micro lens array. The first micro lens array(MLA1) focus the light from DMD to its corresponding pinhole, the second micro lens array( MLA2) then projects image of pinholes array onto substrate to form a points array of light. The substrate is carried by a XY stage, software is developed to synchronize the XY stage moving with DMD. The profile of microlens is design and optimized by a software namely Zemax optics studio to a chieve smallest focused spot size. A technique has been developed to fabricate a large area D-MSFA, which ensures the high accuracy profile and alignment between micro lens arrays and pinhole array. After fabrication, D-MSFA achieves 10μm UV spot sizes at FHMW level. Finally, this study successfully generate arbitrary patterns with the minimum line width is 5 μm.

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