Method of measuring aberration of projection optics
US6011611A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1998 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Nov 5, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70633
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The method of measuring the aberration of the projection optics, according to the present invention includes the following steps. In the first step, the first mask pattern including the first pattern in which a line and space pattern is arranged on a photomask to be linearly symmetrical, and the second pattern in which line patterns having a large line width are arranged on outer sides of the first pattern, to be linearly symmetrical, is transferred on a substrate. In the second step, the second mask pattern in which a patter designed to leave a part of the first pattern and a pattern designed to leave the entire second pattern are arranged to be linearly symmetrical, is transferred on the same substrate, so as to superimpose it on the transferred first pattern. In the third step, the position of the transferred pattern of the second pattern, and the predetermined position of the pattern section of the transferred pattern of the first pattern, which is left in the second step are detected. Thus, from the difference between these positions detected in the third step, the aberration of the projecting optics which is situated between the mask pattern of the photomask and the substrate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.