Accurate contact critical dimension measurement using variable threshold method
US6581023B1 · kind B1 · utility
31Cited by
5References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 7, 2001 |
| Grant date | Jun 17, 2003 |
| Priority date | — |
| Expiry date | Apr 1, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2814
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An embodiment disclosed relates to a variable threshold method of accurately determining a critical dimension (CD) of an integrated circuit feature. This method can include applying a scanning electron microscope (SEM) to an aperture in a layer of material in a portion of an integrated circuit, obtaining a first measurement of a critical dimension of the aperture, applying the SEM again to the aperture, obtaining a second measurement of the critical dimension of the aperture; and determining a depth of focus margin using the first measurement and the second measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.