This chapter provides an overview of the potential applications of excimer laser micromachining. This chapter discusses different laser scanning methods and types of mask projection techniques used in the micromachining process, along with the advantages of mask projection techniques. The KrF excimer laser is highlighted as a potential tool for the micromachining of polymers and metals. The fabrication of microfluidic devices for MEMS applications is discussed, along with large-area fabrication and mask optimization techniques. An algorithm for mask optimization is presented, and the effect of mask shape and size on machining quality using a laser is analyzed. The chapter also includes case studies on various machining scenarios, including the machining of straight and inclined lines with square and circular masks and the machining of circular features with square and circular spots.