Extreme ultraviolet scatterometer: design and capability.
A scatterometer capable of plane-of-incidence bidirectional reflectance distribution function (BRDF) measurements at extreme ultraviolet wavelengths between 58.4 and 121.6 nm has been developed. This instrument has a lower measurement limit of approximately 10(-5) sr(-1), and it is able to accommodate angles of incidence between 10 degrees and 75 degrees . The scatterometer can measure scatter to within 1.5 degrees of the specular beam, and the scatter angle can be measured to within 0.1 degrees . The design, analysis, and performance of this instrument are discussed here. Scatter data, in the form of BRDF measurements, are presented for a 3000-line/mm grating and a flat chemical vapor deposited diamond sample.
Newell
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MP
Keski-Kuha
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RA