Ellipsometric studies on rough Zn and Cd polycrystalline samples

Shehata, Mohamed; Ibrahim, S. S.; Osman, M. H.; Nagib, N. N.

doi:10.21608/jsrs.2020.129799

Ellipsometric studies on rough Zn and Cd polycrystalline samples

Document Type : Original Article

Authors

¹ Secondary Standard Department, National Institute of Standard (NIS), Giza, Egypt.

² Physics department, Faculty of Science, Cairo University, Giza, Egypt

³ National Institute of Standards, Giza, Egypt

10.21608/jsrs.2020.129799

Abstract

A manual null ellipsometer is constructed and used to determine the optical constants of zinc and cadmium of different surface roughness at the wavelength 632.8 nm, angle of incidence 45° and room temperature. The studied samples are polycrystalline sheets of thickness ~ 0.05 mm and surface area 30 mm x 30 mm. The samples were mechanically polished using diamond paste of different grain sizes. The final stage of polishing for the samples was with pastes of grain size 0.5 μm, 2.5 μm, 5 μm, 10 μm and 14 μm. The ellipsometric parameters and were obtained and were used to calculate the optical constants (refractive index) and (extinction coefficient).It was found that as the roughness is increased, the refractive index increases while the extinction coefficient decreases. The used optical arrangement for ellipsometric measurements is presented and the procedure for extracting the results is explained. The uncertainty in the results is calculated and included in the results.

Keywords

References

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