Scatter dots
US6861183B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 2002 |
| Grant date | Mar 1, 2005 |
| Priority date | — |
| Expiry date | Aug 22, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/36
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A mask used for imaging nearly dense features in a substrate. Scatter dots are disposed on the mask in proximity to the nearly dense features, where the scatter dots adjust photon levels of the nearly dense features to a desired level. The adjustment is controlled by selective adjustment of a duty cycle and degree of stagger of the scatter dots. In this manner, the scatter dots adjust the optical properties of the nearly dense features to be very similar to the optical properties of dense features, which enables more accurate imaging of the nearly dense features on the substrate. However, because the scatter dots are discontinuous, they do not overcorrect in the same manner that a scatter bar formed at a minimum resolution might overcorrect. Further, there is a reduced likelihood that the scatter dots would actually print on the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.