The Development of SOR Lithography Technology

This paper reviews NTT Laboratories' research and development of x-ray lithography during the last ten years since the application of synchrotron orbital radiation(SOR). First, the historical background of x-ray lithograhpy research, NTT's research programs on synchrotron x-ray lithography(SOR lithography), and the current status of NTT's SOR lithography system are overviewed. Then, the key elements of SOR lithography system are reviewed, including the electron storage ring, the x-ray stepper, and the x-ray mask. Finally the appilcation of SOR lithography technology to device fabrication is reported.