Apparatus for determining an overlay error and critical dimensions in a semiconductor structure by means of scatterometry
US6816252B2 · kind B2 · utility
3Cited by
14References
14Claims
0Family size
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Key dates
| Filing date | Apr 29, 2002 |
| Grant date | Nov 9, 2004 |
| Priority date | — |
| Expiry date | Sep 4, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2210/56
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for obtaining information on critical dimensions and overlay accuracy of features in a semiconductor structure comprises a light source, a detector and an optical means defining a first optical path and a second optical path. The first optical path and the second optical path are oriented in correspondence with the respective orientations of diffracting patterns provided on the semiconductor structure to obtain the required information without the necessity of rotating the semiconductor structure. This insures a significantly higher throughput.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.