Use Of X-Ray Exposure In The Manufacture Of Sub 150nm Gate Lines

X-ray exposures performed at IBM's Advanced Lithography Facility (ALF) in Hopewell Junction, New York has led to the ability to routinely print sub 250nm discrete devices in photoresist. When fully processed, the resulting electrical channel length for these devices is below 150nm leading to average switching delays of 35 picoseconds. Sub 150nm devices with resulting electrical channel lengths of 100nm have also been made producing switching delays of 20 picoseconds, which are among the fastest reported in CMOS technology. In addition to the discrete devices, fully functional 0.25um 64Kb SRAMs were fabricated with an approximate 40 percent chip yield on the best wafer. Recent improvements in the overall lithographic process have enabled the gate line to be printed at sub 125nm. The resulting electrical channel is below 100nm. Device performance is expected to be faster at these smaller dimensions. The results obtained are based on several lots of 200mm wafers processed with the use of mix and match (x-ray to optical) steppers. The results can be viewed as current x-ray lithography in ALF.