| 摘要 |
<p>A method of detecting defects in a reticle used to fabricate semiconductor circuits by enhancing the image of a defect in one chip site without appreciably changing all other chip site images. In a step-and-repeat alignment system, a first chip site is exposed under normal intensities to print the reticle pattern at a proper exposure level. At a second chip site, exposure takes place using the same reticle (or a second identical reticle) at lower intensity levels. Given this underexposure, residual photoresist will remain at defect sites. The optical imagery at the two chip sites is different allowing comparator techniques to be used.</p> |
