Laser processing of light reflective multilayer target structure
US7741131B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 2007 |
| Grant date | Jun 22, 2010 |
| Priority date | — |
| Expiry date | May 25, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A solution to an interference effect problem associated with laser processing of target structures entails adjusting laser pulse energy or other laser beam parameter, such as laser pulse temporal shape, based on light reflection information of the target structure and passivation layers stacked across a wafer surface or among multiple wafers in a group of wafers. Laser beam reflection measurements on a target link measurement structure and in a neighboring passivation layer area unoccupied by a link enable calculation of the laser pulse energy adjustment for a more consistent processing result without causing damage to the wafer. For thin film trimming on a wafer, similar reflection measurement information of the laser beam incident on the thin film structure and the passivation layer structure with no thin film present can also deliver the needed information for laser parameter selection to ensure better processing quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.