Multi-pitch and line calibration for mask and wafer CD-SEM system
US6570157B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 2000 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Nov 10, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/682
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention relates to a system and method for calibrating a scanning electron microscope (SEM). The method comprises using a reference having multiple features of different dimensions and spatial interrelationships, wherein more than one feature dimension or spacing is measured using the SEM prior to measuring a workpiece. The dimensional and/or spatial measurements from the reference sample are correlated to obtain one or more calibration factors for the SEM. The calibration factor or factors may then be correlated with a workpiece SEM measurement to obtain a workpiece critical dimension (CD). A system is provided for calibrating a SEM including a reference with various measurable features of different dimensions and/or spacing. The system comprises an SEM to measure one or more reference sample feature dimensions and/or spacings and a processor or other device to correlate the measurement data to obtain one or more calibration factors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.