Development of element technologies for EUVL

Thirty years have passed since the first report on extreme ultraviolet lithography (EUVL) was presented at the annual meeting of the Japanese Society of Applied Physics in 1986. This technology is now in the manufacturing development stage. The high-volume manufacturing of dynamic-random-access-memory (DRAM) chips with a line width of 15 nm is expected in 2016. However, there are critical development issues that remain: generating a stand-alone EUV source with a higher power and producing a mask inspection tool for obtaining zero-defect masks. The Center for EUVL at the University of Hyogo was established in 2010. At present, it utilizes various types of equipment, such as an EUV mask defect inspection tool, an interference-lithography system, a device for measuring the thickness of carbon contamination film deposited by resist outgassing, and reflectivity measurement systems.