Contact opening metrology
US7381978B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 2005 |
| Grant date | Jun 3, 2008 |
| Priority date | — |
| Expiry date | Feb 3, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3011
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for process monitoring includes receiving a sample having a first layer that is at least partially conductive and a second layer formed over the first layer, following production of contact openings in the second layer by an etch process, the contact openings including a plurality of test openings having different, respective transverse dimensions. A beam of charged particles is directed to irradiate the test openings. In response to the beam, at least one of a specimen current flowing through the first layer and a total yield of electrons emitted from a surface of the sample is measured, thus producing an etch indicator signal. The etch indicator signal is analyzed as a function of the transverse dimensions of the test openings so as to assess a characteristic of the etch process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.