Mask fabrication is a process in which masks, also known as photomasks, are created for use in photolithography. These masks are crucial in the production of integrated circuits, as they contain the necessary patterns for transferring circuit designs onto wafers during the lithography process. The fabrication of masks typically involves several steps, including the design of the mask pattern using computer-aided design software, the deposition of various materials onto a substrate, and the etching of the pattern onto the mask surface. Advanced techniques such as electron beam lithography and deep-ultraviolet lithography are often used to create high-resolution masks with precise features. Mask fabrication is a critical aspect of semiconductor manufacturing, as the accuracy and quality of the masks directly impact the performance and functionality of the final integrated circuits. Research in this area focuses on developing new materials, processes, and technologies to improve mask fabrication techniques and ensure the continued advancement of semiconductor technology.