End point detection in time division multiplexed etch processes
US6982175B2 · kind B2 · utility
5Cited by
10References
20Claims
0Family size
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Key dates
| Filing date | Feb 2, 2004 |
| Grant date | Jan 3, 2006 |
| Priority date | — |
| Expiry date | Feb 9, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An improved method for determining endpoint of a time division multiplexed process by monitoring an identified region of a spectral emission of the process at a characteristic process frequency. The region is identified based upon the expected emission spectra of materials used during the time division multiplexed process. The characteristic process frequency is determined based upon the duration of the steps in the time division multiplexed process. Changes in the magnitude of the monitored spectra indicate the endpoint of processes in the time division multiplexed process and transitions between layers of materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.