Method and apparatus for monitoring exposure process
US7685560B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2004 |
| Grant date | Mar 23, 2010 |
| Priority date | — |
| Expiry date | Jul 1, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70683
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exposure process monitoring method capable of performing quantitative monitoring of an exposure amount and a focusing position which are major process parameters during exposure using a Levinson phase shift mask in semiconductor lithography processes is disclosed. During exposure using the Levinson phase shift mask, the focus position is influenceable by optical intensity distribution characteristics so that it can vary from its minus (−) to plus (+) directions by in a way depending upon the pitch width and line width of a line-and-space pattern. In such case, there exist a pattern in which the cross-sectional shape of a resist changes from a forward taper to reverse taper and a pattern in which the sectional shape changes from the reverse to forward taper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.