Method of cleaning a photo-mask
US4569695A · kind A · utility
65Cited by
7References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1984 |
| Grant date | Feb 11, 1986 |
| Priority date | — |
| Expiry date | Apr 20, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67051
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A photo-mask to be used in a light exposure step for manufacturing semiconductor devices is cleaned by wetting front and rear surfaces of the mask with a liquid, brushing the wetted surfaces with a pair of rotary brushes, wetting the brushed surfaces with an electrolytic solution containing sufficient electrolyte to substantially eliminate electrostatic charge from the surfaces, spraying and immersing the photo-mask in an organic liquid such as an alcohol, and then drying the photo-mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.