Free form fracturing method for electronic or optical lithography using resist threshold control
US9891519B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2014 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Oct 27, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31776
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A computer implemented method of fracturing free form target design into elementary shots for defined roughness of the contour comprises determining a first set of shots which pave the target design and determining a second set of shots to fill the gaps. The dose levels of overlapping shots in the first or second sets of shots are determined so the compounded dose is adequate to the resist threshold, considering the proximity effect of the actual imprint of shots on the insulated target. A dose geometry modulation is applied and rounded shot prints are produced by shots not circular that may overlap. The degree of overlap is determined as a function of desired optimization of fit criteria between a printed contour and the contour of the desired pattern. Placements and dimensions of the shots are determined by a plurality of fit criteria between printed contour and contour of the desired pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.