In-line overlay measurement using charged particle beam system
US8010307B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 2007 |
| Grant date | Aug 30, 2011 |
| Priority date | — |
| Expiry date | Mar 7, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/20
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method and system for controlling an overlay shift on an integrated circuit is disclosed. The method and system comprises utilizing a scanning electron microscope (SEM) to measure the overlay shift between a first mask and a second mask of the circuit after a second mask and comparing the overlay shift to information about the integrated circuit in a database. The method and system includes providing a control mechanism to analyze the overlay shift and feed forward to the fabrication process before a third mask for error correction. A system and method in accordance with the present invention advantageously utilizes a scanning electron microscope (SEM) image overlay measurement after the fabrication process such as etching and chemical mechanical polishing (CMP).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.