Mask for use in measuring flare, method of manufacturing the mask, method of identifying flare-affected region on wafer, and method of designing new mask to correct for flare
US6835507B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 2002 |
| Grant date | Dec 28, 2004 |
| Priority date | — |
| Expiry date | Dec 26, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70941
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A mask for use in measuring flare produced by a projection lens of a photolithography system, a method of manufacturing the mask, a method of identifying a flare-affected region on a wafer, and a method for correcting for the flare to produce photoresist patterns of desired line widths are provided. A first photolithographic process is performed to form photoresist patterns on a test wafer using a mask including a light shielding region having a plurality of light transmission patterns and a light transmission region, and the photoresist patterns formed by light passing through the light transmission patterns of the light shielding region are compared to the photoresist patterns formed by light passing through the light transmission region. The amount of flare produced by the projection lens is quantified using the results of the comparison, and thus it is possible to identify a flare-affected region on the wafer. In addition, it is possible to form uniform photoresist patterns on the wafer by determining the open ratio of the flare-affected region and calculating an effective amount of the flare in the flare-affected region from the amount of flare of the lens and the open ratio. …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.