Multiple pulse space processing to enhance via entrance formation at 355 nm
US5841102A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 8, 1996 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | Nov 8, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/1383
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for forming a through-via in a laminated substrate by laser drilling a through-via from a top exposed surface of the substrate to a bottom exposed surface of the substrate using a plurality of laser pulses that are spaced at the first pulse spacing. Each pulse spaced at the first pulse spacing has a first energy density per pulse. Then, the through-via is laser drilled using a plurality of laser pulses that are trepanned at a second pulse spacing. Each pulse spaced at the second pulse spacing has a second energy density per pulse. The second energy density per pulse is greater than the first energy density per pulse, and the second pulse spacing is less than the first pulse spacing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.