Methods for forming and cleaning photolithography reticles
US7767365B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 2006 |
| Grant date | Aug 3, 2010 |
| Priority date | — |
| Expiry date | Sep 20, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/80
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for removing impurities (e.g., atomic sulfur) from a reticle for use in photolithography is provided. In one embodiment, a reticle (or photomask) comprising a plate, a first layer over the plate, and a photoresist layer over the first layer is provided. The photoresist layer is removed with a first chemistry comprising a sulfur-containing compound. At least a portion of the first layer is removed with a second chemistry comprising a sulfur-containing etchant, thereby exposing portions of the plate. Removing the photoresist layer and/or at least a portion of the first layer leaves sulfur on at least portions of the reticle. In a cleaning step, the reticle is contacted with one or more excited species of oxygen to remove residual sulfur and other contaminants, such as carbon, sulfur and oxygen-containing species. Methods of embodiments can be used to clean, e.g., binary photomasks, attenuated phase shift masks (APSMs) and high transmission attenuated photomasks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.