Installation for etching material
US4741798A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 12, 1986 |
| Grant date | May 3, 1988 |
| Priority date | — |
| Expiry date | Nov 12, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/068
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an installation for etching material to be etched consisting at least partly of metal, preferably copper, oxidizing agent is added to the etching medium containing an acid, directly before the actual etching operation, in a quantity which is in a ratio to the quantity required according to stoichiometric calculation for etching the quantity of metal to be removed respectively from the material to be etched. For this a device is provided which emits a first electrical signal. This gives information about the quantity of material to be removed from the material to be etched respectively being processed. A second signal is emitted by a detector when the material to be etched enters the actual etching machine. Both signals are processed by a central control unit. This takes place in such a way that the central control unit emits a third signal which it has ascertained according to a memorized program from the first signal and whenever the detector signal is received. The third signal corresponds to the respectively desired quantity of oxidizing agent and acts on a metering device which then undertakes measuring of the quantity of oxidizing agent. In the same way acid may be added to…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.