Method for backside alignment of photo-processes using standard front side alignment tools
US6861186B1 · kind B1 · utility
15Cited by
5References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 25, 2003 |
| Grant date | Mar 1, 2005 |
| Priority date | — |
| Expiry date | Sep 25, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7084
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image of an integrated circuit chip and optical kerf and their mirror image are formed within a single optical field. When a substrate pattern using this process is flipped over or reversed, the processed pattern appears the same as on the first side, equal to its own mirror image. Prior to the backside lithography, a portion of the second side is removed to allow detection of alignment marks on the first side from the second side of the substrate. Once the alignment marks are detected, the lithography continues as though the substrate was not flipped over at all.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.