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ULSI has heavily depended on develops in optical lithography. However, optical lithography is now facing a major obstacle due to exposure wavelength limitations. To overcome this obstacle, not only the use of shorter wavelengths, but also such new technologies as super-resolution techniques, electron beams, and X-ray lithography are being intensively investigated. This paper reviews recent developments in these technologies and discusses the major issues. The difference in lithographic activities between Japan and the U.S. is also discussed. Finally, recent developments in lithography for experimental 1-Gb DRAMs are presented.