Parallel micro manipulator for optical spot array alignment of maskless lithography

Abstract

Photolithography is the one of the core processes in micro-nano fabrication that includes micro electro mechanical system devices, flat panel displays, and various semiconductor chips. Since manufacturing of masks takes major portion of overall cost structure for the typical lithography procedure, elimination of the masks from the process will make a great impact on cost reduction. In addition, the maksless lithography generally provides a great flexibility for product design and verification. Firstly, In the present work, it was introduced that a point array method applied to Digital Micro mirror Device (DMD)-based optical head system in maskless digital exposure process. Secondly, it was shown the design of a redundant 4-[PP]PS parallel mechanism and analysed kinematic characteristic of the parallel manipulator. An array error model of the system is defined and application of genetic algorithm to the alignment spot array position error correction is presented. Finally, the system is tested and analyzed with a 10 by 10 optical array setup.