Method of photolithographic exposure dose control as a function of resist sensitivity
US6674516B2 · kind B2 · utility
2Cited by
12References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2002 |
| Grant date | Jan 6, 2004 |
| Priority date | — |
| Expiry date | Feb 20, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70608
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A predictive method is used to compensate for intermediate batch sensitivities which inevitably occur during resist batch changeover. The compensation is applied to historical dose levels to arrive at a new dose level estimating an optimum dose. When the system discovers that a new batch of resist is loaded to a tool, historical data is used to calculate a reference dose for each tool. A batch factor is continuously calculated and using historical data along with the batch factor, a dose adjustment is made to maintain proper image size.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.