Region-Based Pattern Generation Scheme for DMD Based Maskless Lithography

摘要

We focus our attention on complex lithographic pattern generation on a huge substrate with no manipulation of the light source shape for Digital Micromirror Device (DMD) based maskless lithography. To overcome the limitations of existing pattern generation methods developed upon the assessment of lithographic paths of the reflected beam spots rather than the recognition of patterns, we place our primary concern on the pattern. We consider pattern generation for mask-less lithography using the DMD as a graphic recognition field problem. The pattern generation process is conceptualized as dual pattern recognition in two contrary views, which are the substrate's view and the DMD's view. For pattern recognition in the DMD's view, a unique criterion, the area ratio, is devised for approval of the on/off reflection of the DMD mirror. The Region-based Pattern Generation (RPG) scheme based upon the area ratio is proposed. For verification, a prototype RPG system is implemented, and lithography using the system is performed to fabricate an actual Flat Panel Display (FPD) glass. The results verify that the RPG scheme is robust enough to generate lithographic patterns in any possible lithographic configuration and the RPG system is precise enough to attain the lithographic quality required by the FPD manufacturer.