Ultrasonic glow discharge surface cleaning
US5068002A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 3, 1989 |
| Grant date | Nov 26, 1991 |
| Priority date | — |
| Expiry date | Aug 3, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/26
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An apparatus is disclosed for abrading contaminants from the surface of a workpiece using plasma glow discharge. The workpieces are positioned in a low pressure chamber with an ionizable gas. A pair of spaced, conductive, interfacing panels form electrodes mounted within the chamber and defining a three-dimensional cleaning space between the electrodes. The electrodes are energized by a power supply, providing an alternative voltage at an ultrasonic frequency and the pressure is maintained to allow only abnormal glow discharge. After initiation of the abnormal glow discharge the electrode current is sensed to detect when to inject additional ionizable gas into the low pressure chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.