Method of monitoring an exposure process
US6929892B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 2004 |
| Grant date | Aug 16, 2005 |
| Priority date | — |
| Expiry date | Jul 20, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/143
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In monitoring of an exposure process, a highly isolative pattern greatly changed in a shape of cross section by fluctuations in the exposure dose and the focal position is an observation target. Especially, to detect a change in a resist shape of cross section from a tapered profile to an inverse tapered profile, one of the following observation methods is employed to obtain observation data: (1) a tilt image of a resist pattern is imaged by using tilt imaging electron microscopy, (2) an electron beam image of a resist pattern is imaged under imaging conditions for generating asymmetry on an electron beam signal waveform, and (3) scattering characteristic data of a resist pattern is obtained by an optical measurement system. The observation data is applied to model data created beforehand in accordance with the exposure conditions to estimate fluctuations in the exposure dose and the focal position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.