摘要 |
A foreign particle inspection arrangement includes an optical illumination system that irradiates a predetermined area of a substrate surface with fluorescence exciting ultraviolet light pulses. Fluorescence from a foreign particle on the substrate is directed by an optical detection system to a photoelectric transducer which detects accumulation of fluorescence in response to plural ultraviolet light pulses. An electrical processing system inspects the adherence of the foreign particle to the substrate on the basis of the photoelectric transducer output. A position determining type of photoelectric transducer such as a charge coupled array or pickup tube may be used to determine the position of the foreign particle to avoid misdetection due to readherence. The illumination of a large area keeps the radiation density low to prevent damage to a reticle pattern on the substrate.
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