Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1542830 | Optics Communications | 2006 | 5 Pages |
Abstract
In this paper, we present a simple system for defect enhancement in periodic masks, enabling in this way their rapid localization. The system uses the fact that periodic structures under coherent illumination generate replicas of itself displaced half period at certain distances (1/2-Talbot's length). Projecting back this displaced self-image onto the mask creates a suppression of the periodic structure. If the mask presents defects, the cancellation of the periodic structure allows their detection since the self-imaging phenomenon occurs only for the periodic structure. The technique may be applied to transmission masks like semiconductor wafers, photomasks for integrated circuits or LCD panels.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Eugenio Garbusi, José A. Ferrari,