Damage isolation by shaped beam delivery in laser scribing process
US9029242B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 2011 |
| Grant date | May 12, 2015 |
| Priority date | — |
| Expiry date | Sep 19, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/334
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Methods and apparatuses for dicing substrates by both laser scribing and plasma etching. A method includes laser ablating material layers, the ablating by a laser beam with a centrally peaked spatial power profile to form an ablated trench in the substrate below thin film device layers which is positively sloped. In an embodiment, a femtosecond laser forms a positively sloped ablation profile which facilitates vertically-oriented propagation of microcracks in the substrate at the ablated trench bottom. With minimal lateral runout of microcracks, a subsequent anisotropic plasma etch removes the microcracks for a cleanly singulated chip with good reliability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.