Hitachi-high-technologies Corporation

Kenichiro Komeda

Kenji Oka

Kenji Mitomo

While an illumination optical system is irradiating the surface of a contaminated standard wafer with illumination light, this illumination light is scanned over the surface of the contaminated standard wafer, then detectors of a detection optical system each detect the light scattered from the surface of the contaminated standard wafer, next a predefined reference value in addition to detection results on the scattered light is used to calculate a compensation parameter 'Comp' for detection sensitivity correction of photomultiplier tubes of the detectors, and the compensation parameter 'Comp' is separated into a time-varying deterioration parameter &#x201c;P&#x201d;, an optical characteristics parameter &#x201c;Opt&#x201d;, and a sensor characteristics parameter &#x201c;Lr&#x201d;, and correspondingly managed. This makes is easy to calibrate the detection sensitivity.

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Kumamoto, Japan

Kenichiro Komeda