Method for controlling a line dimension arising in photolithographic processes
US5516608A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1994 |
| Grant date | May 14, 1996 |
| Priority date | — |
| Expiry date | Feb 28, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70675
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a photolithographic process utilizing a wafer coated with a chemically amplified photoresist, a method for controlling a line dimension. The method comprises the steps of measuring at at least two times, and from at least two angles, evolving signals comprising intensities of light diffracted from a portion of an exposed patterned area on the waver, the evolving signals corresponding to vector combinations of time dependent light diffracted from the pattern appearing in the photoresist; and substantially time invariant light diffracted due to any underlying pattern beneath the photoresist; and, combining the measurements mathematically for extracting a contribution due to the pattern evolving in the photoresist.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.