Metal sublayer sensing in multi-layer workpiece hole drilling
US10933490B2 · kind B2 · utility
1Cited by
7References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 22, 2016 |
| Grant date | Mar 2, 2021 |
| Priority date | — |
| Expiry date | Aug 25, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/107
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed herein is a method of drilling in a multilayer printed circuit board. The method includes drilling a one hole; directing electromagnetic radiation having at least one wavelength with higher energy than a work-function the metal layer toward the hole, and thus causing the metal layer to emit free electrons; and measuring the quantity or intensity of electrically charged particles derived from the emitted free electrons, to detect the extent of exposure or disappearance of the metal layer during drilling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.