Variable-Angle Spectroellipsometric Characterization of CdS Thin Films

Year 2014, Volume: 9 Issue: 2, 137 - 146, 31.12.2014

Olcay Gençyılmaz , Ferhunde Atay , İdris Akyüz

Abstract

In this work, CdS thin films produced by ultrasonic spray pyrolysis technique. The optical properties of CdS thin films were investigated using spectroscopic ellipsometry and UV-VIS Spectrophotometer. The optical properties of CdS thin films coated glass substrates were evaluated by variable-angle spectroscopic ellipsometry. Variable angle spectroscopic ellipsometry was used for thickness and optical constant calculations. Multiple angle measurements were taken in the most sensitive angle of incidence region. Appropriate incident angle were obtained as experimental using graph of ψ and Δ. Cauchy-Urbach model was used to determine the thickness, refractive index and extinction coefficient for CdS thin films. Also, transmittance measurements and band gap values of the films was examined by UV-VIS spectrophotometer and optical method, respectively. Finally, the incidence angle effects were discussed on the optical properties of CdS thin films such as thickness and optical constant (refractive index and extinction coefficient)

Keywords

CdS thin film, spectroscopic ellipsometry, thickness, optical constants and transmittance

CdS İnce Filmlerinin Değişik Açılarda Spektroelipsometrik Karakterizasyonu

Abstract

Bu çalışmada, CdS ince filmleri ultrasonik kimyasal püskürtme tekniği kullanılarak üretildi. CdS ince filmlerinin optik özellikleri spektroskopik elipsometre ve UV-VIS spektrofotometre kullanılarak belirlendi. Cam tabanlar üzerine depolanan CdS ince filmlerinin optik özellikleri değişken açılardaki spektroskopik ellipsometre ölçüleri kullanılarak incelendi. Kalınlıkların ve optik sabitlerin hesaplamaları değişken açılardaki elipsometrik ölçümler kullanılarak yapıldı. En duyarlı gelme açısını belirlemek için çeşitli açılarda ölçümler yapıldı. Uygun gelme açısı, ï¹ ve ï„ grafikleri kullanılarak deneysel olarak elde edildi. CdS ince filmlerinin kalınlıklarını, kırılma indisi ve sönüm katsayısı değerlerini belirlemek için Cauchy-Urbach modeli kullanıldı. Ayrıca, geçirgenlik ölçümleri ve bant aralığı değerleri sırasıyla UV-VIS spektrofotometre ve optik metot kullanılarak belirlendi. Sonuç olarak, CdS ince filmlerinin kalınlık ve optik sabitler (kırılma indisi ve sönüm katsayısı) gibi optik özelikleri üzerine gelme açısının etkileri tartışılmıştır.

Keywords

CdS ince filmleri, spektroskopik elipsometre, kalınlık, optik sabitler, geçirgenlik

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• Ferhunde Atay e-mail: [e-mail]
• İdris Akyüz e-mail: [e-mail]