Mask quality measurements by fourier space analysis
US6187483A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1999 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | May 28, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/36
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method (200) of determining an optimal mask fabrication process includes fabricating (202) a first mask pattern (220) on a mask using a first mask fabrication process and a second mask pattern (222) on a mask using a second mask fabrication process, wherein each mask pattern approximates an ideal pattern. The method (200) further includes performing a mathematical transform on the first and second mask patterns (230), wherein the mathematical transform provides a representation of the first and second mask patterns as sums of functions. A metric is then obtained for the transformed mask patterns (220, 222), wherein the metric is based upon a capability of a pattern transfer system which will utilize the masks employing the first and second mask patterns one of the first and second mask fabrication processes is selected (236) based upon an application of the metric to the first and second sum of orthogonal functions, thereby selecting the one of the first or second mask fabrication processes that provides for a better mask pattern which most closely approximates the ideal mask pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.