Advanced DUV photolithography in a pilot line environment

As the critical path to increasing circuit density, deep-ultraviolet (DUV) lithography has played a key role in the development of new semiconductor products. At present, DUV refers to imagery at the 248-nm wavelength, with the introduction of 193-nm photolithographic systems anticipated in the next few years. This paper presents an overview of DUV lithography applications in the IBM Advanced Semiconductor Technology Center (ASTC). Since 1990, we have used DUV lithography for critical levels of advanced generations of DRAM (64Mb, 256Mb, and 1Gb) and associated families of logic products. We describe the means by which DUV capability and productivity have increased in a decreasing process window environment. Tooling, processes, and process control systems have undergone continuous improvement to accommodate increasing wafer starts and the rapid introduction of new products.