Imaging tool calibration artifact and method
US7473502B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 3, 2007 |
| Grant date | Jan 6, 2009 |
| Priority date | — |
| Expiry date | Aug 3, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/706
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of determining and correcting for distortions introduced by an imaging tool. The method includes providing an imaging tool having a field of view (FOV), and creating a target pattern containing a regular array of symmetric sub-patterns having locations spanning the FOV. Using the imaging tool, the method then includes measuring relative position of the sub-pattern images at one or more target orientations, determining tool-induced sub-pattern position deviations from designed locations of the sub-patterns, and applying corrections to compensate for an orientation independent component of the sub-pattern position deviations. The target pattern may be mounted on a stage of the measurement tool, created on a mask used in the lithographic process, or created on a wafer being measured by the measuring tool.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.