Method for dust-proofing in the manufacture of electronic devices and pellicle therefor
US5254419A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 6, 1992 |
| Grant date | Oct 19, 1993 |
| Priority date | — |
| Expiry date | Jan 6, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/62
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed is a method for dust-proofing of a photomask in the photolithographic processing of electronic devices, e.g., LSIs and liquid-crystal display panels, in which the photomask is covered with a pellicle having a frame-supported light-transmitting membrane made from a polyvinyl alcohol modified by silylating the hydroxy groups of the polyvinyl alcohol with triorganosilyl groups of the formula R.sub.3 Si--, in which R is a monovalent hydrocarbon group, e.g., alkyl, in a degree of substitution of at least 40%. The membrane of the pellicle is highly transparent to light of short wavelength in the ultraviolet region and excellently durable under prolonged irradiation with ultraviolet light not to cause yellowing or mechanical breaking.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.