Lithography Alignment Technologies: A Comprehensive Review of Advances and Challenges

ABSTRACT Lithography alignment, a core process in micro–nano fabrication, has evolved from the micron scale to the nanometer and even sub‐nanometer domain. However, this advancement has introduced unprecedented challenges related to precision, speed, and reliability. During multilayer pattern exposure, lithography alignment is crucial for achieving high‐resolution and accurate pattern transfer, which directly influences device performance and yield, ultimately determining the overall effectiveness and efficiency of the lithography process. This review provides a comprehensive overview of the development and key technological advancements in lithography alignment. First, recent breakthroughs in alignment mark optimization, signal enhancement, and compensation for asymmetric deformation of the mark are discussed. Next, the evolution of pre‐alignment, coarse alignment, and fine alignment technologies is outlined, including a systematic comparison of the alignment strategies adopted by major lithography machine manufacturers, such as ASML, Nikon, and Canon. Subsequently, the principles, implementations, advantages, and challenges of core technologies, including interferometric alignment, image‐processing‐based alignment, and grating‐modulated alignment, are reviewed. Additionally, the alignment requirements for advanced lithography technologies are discussed. Lastly, the open challenges associated with lithography alignment are highlighted, along with potential future trends and research directions. This review contributes to the literature by consolidating recent advancements and critically comparing current methodologies for lithography alignment.