Method for chemically treating a single side of a workpiece
US4165252A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 6, 1978 |
| Grant date | Aug 21, 1979 |
| Priority date | — |
| Expiry date | Mar 6, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D11/32
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method for chemically treating a single side of a workpiece, such as for etching or anodizing a semiconductor wafer, comprising, placing such a workpiece face down on a flat centrally apertured, relatively level table having a top or work surface of a size and shape commensurate with the dimensions of the workpiece and introducing the liquid for the chemical treatment between the top surface and side of the workpiece to be treated where the liquid passes over the entire surface to be treated and then returns to its source. The method also includes, for certain applications, a pre-processing of the workpiece by oxidizing the workpiece surface on the side of the workpiece opposite of the one to be treated to be treated to prevent creeping of the liquid around the edges thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.