Manufacturing issues are often uncovered only after a new lithography solution enters full production. Franklin, as our resident mask expert, perhaps you could give us some examples of mask-specific "gotchas" for 193 nm lithography (dry and wet). Also, do you have any predictions about what sort of things might pop up for EUV or nanoimprint?
Sorry I've been out for a few days. I hope this forum is still active.
Two specific "gotchas" in ArF lithography were haze/durability and matching to existing processes. We had seen haze in KrF litho, but the extent to which it was observed at 193nm was generally unanticipated. Likewise, matching between mask providers has become much more challenging at ArF than it was at KrF, increasing the cost of qualifying more than one mask supplier at a wafer fab.
For EUV, an easily predictable gotcha is mask durability: not necessarily haze (although that might occur), perhaps film stability.
For NIL, I think contamination will be a defining issue in high volume manufacturing.
You bring up several interesting points, Franklin. Somebody was asking me recently about haze issues in ArF lithography. I know that the higher-energy wavelength of 193 nm created some pretty nasty (and costly) problems. Has haze been sufficiently compensated for, or is it still a significant issue?
Will the mask durability/film stability issue that's likely to come with EUV be caused also by the even shorter wavelength?
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