Focus control method for photolithography
US8772054B2 · kind B2 · utility
1Cited by
4References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 8, 2011 |
| Grant date | Jul 8, 2014 |
| Priority date | — |
| Expiry date | Oct 19, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7053
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method comprises providing a semiconductor substrate having at least one layer of a material over the substrate. A sound is applied to the substrate, such that a sound wave is reflected by a top surface of the layer of material The sound wave is detected using a sensor. A topography of the top surface is determined based on the detected sound wave. The determined topography is used to control an immersion lithography process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.