Determining endpoint in a substrate process
US7808651B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 2010 |
| Grant date | Oct 5, 2010 |
| Priority date | — |
| Expiry date | Jan 15, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32963
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An endpoint detection system for detecting an endpoint of a process comprises a polychromatic light source which emits polychromatic light. The light is reflected from a substrate. A light wavelength selector receives the reflected polychromatic light and determines a wavelength of light at which a local intensity of the reflected light is maximized during the process. In one version, the wavelength selector comprises a diffraction grating to generate a plurality of light beams having different wavelengths from the reflected polychromatic light and a light detector to receive the light beams having different wavelengths and generate an intensity signal trace of the intensity of each wavelength of the polychromatic reflected light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.