Lithographic processing optimization based on hypersampled correlations
US8120748B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 2007 |
| Grant date | Feb 21, 2012 |
| Priority date | — |
| Expiry date | Jul 15, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70425
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of optimizing lithographic processing to achieve substrate uniformity, is presented herein. In one embodiment, The method includes deriving hyper-sampled correlation information indicative of photoresist behavior for a plurality of wafer substrates processed at pre-specified target processing conditions. The derivation includes micro-exposing subfields of the substrates with a pattern, processing the substrates at the various target conditions, determining photoresist-related characteristics of the subfields (e.g., Bossung curvatures), and extracting correlation information regarding the subfield characteristics and the different target processing conditions to relate the target conditions as a function of subfield characteristics. The method then detects non-uniformities in a micro-exposed subsequent substrate processed under production-level processing conditions and exploits the correlation information to adjust the production-level conditions and achieve uniformity across the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.