Process and circuitry for generating current pulses for electrolytic metal deposition
US6132584A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 4, 1998 |
| Grant date | Oct 17, 2000 |
| Priority date | — |
| Expiry date | Jun 4, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D5/18
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention relates to a method of generating short, cyclically repeating, unipolar or bipolar pulse currents I.sub.G, I.sub.E for electroplating, and to a circuit arrangement for electroplating with which pulse currents I.sub.G, I.sub.E can be generated. Electroplating methods of this type are referred to as pulse-plating methods. According to the invention, the secondary winding 6 of a current transformer 1 is connected in series into the electroplating direct current circuit 5, consisting of a bath direct current source 2 and a bath which is contained in an electroplating cell and which is represented by resistor R.sub.B. The primary winding 7 of the transformer has a larger number of turns than the secondary winding. The primary winding is controlled with pulses of high voltage and with relatively low current. The high pulse current on the secondary side temporarily compensates in pulses the electroplating direct current. This compensation can be a multiple of the electroplating current, such that deplating pulses with high amplitude are produced. The capacitor 10 guides the compensating current through charging and discharging. Through the invention, the necessity of using i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.