Alignment technique using heterodyne interferometer in conjugate relation for wafer stepper.
نویسندگان
چکیده
منابع مشابه
Heterodyne displacement interferometer, insensitive for input polarization.
Periodic nonlinearity (PNL) in displacement interferometers is a systematic error source that limits measurement accuracy. The PNL of coaxial heterodyne interferometers is highly influenced by the polarization state and orientation of the source frequencies. In this Letter, we investigate this error source and discuss two interferometer designs, designed at TU Delft, that showed very low levels...
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ژورنال
عنوان ژورنال: Journal of the Japan Society for Precision Engineering
سال: 1991
ISSN: 1882-675X,0912-0289
DOI: 10.2493/jjspe.57.262