Dual-sided substrate measurement apparatus and methods
US7902040B1 · kind B1 · utility
0Cited by
3References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2008 |
| Grant date | Mar 8, 2011 |
| Priority date | — |
| Expiry date | Aug 25, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7088
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An apparatus for measuring the relative positions of frontside and backside alignment marks located on opposite sides of a substrate is disclosed. The apparatus includes upper and lower optical systems that allow for simultaneous imaging of frontside and backside alignment marks. The frontside and backside alignment mark images are processed to determine the relative position of the marks, as a measurement of the alignment and/or overlay performance of the tool that formed the marks on the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.