Farklı pH Değerlerinde Elde Edilen Kadmiyum Sülfür Filmlerinin Fiziksel Özellikleri

Bu çalışmada, kimyasal banyo depolama metodu kullanılarak 80 °C banyo sıcaklığında cam tabanlar üzerine farklı pH değerlerinde (10,00; 10,10; 10,20; 10,30) kadmiyum sülfür yarıiletken filmleri elde edilmiştir. Elde edilen filmlerin X-ışını kırınım desenlerinden kübik fazda oluştuğu görülmüştür. Filmlerin soğurma ve geçirgenlik spektrumları UV-Vis spektrofotometre ile alınmıştır. Filmlerin bant aralığı değerleri görünür bölgedeki soğurma spektrumu ölçümlerinden elde edilmiştir. Filmlerin yasak enerji bant aralığı değerlerinin artan pH değerleriyle birlikte azaldığı ve 2,42-2,38 eV arasında değiştiği tespit edilmiştir. Filmlerin görünür bölgedeki optik geçirgenlik değerleri %84-65 arasında değiştiği bulunmuştur. Filmlerin yüzey özellikleri ve pürüzlülük değerleri atomik kuvvet mikroskobu kullanılarak belirlenmiştir. FESEM görüntülerinden filmlerin genellikle küresel yapıda homojen dağılım gösterdiği gözlenmiştir. Filmlerin elemental bileşimini tayini EDX kullanılarak yapılmıştır

Physical Properties of Cadmium Sulphur Films Obtained at Different pH Values

Cadmium sulphide films have been deposited onto the glass substrates by chemical bath deposition method at different pH values (10.00, 10.10, 10.20, 10.30) at 80 oC. X-ray diffraction spectra of the films have shown that the films are cubic in structure. To determine the optical properties of the CdS films UV-vis spectrophotometer was used. Optical absorption and transmittance optical values of the films were determined from the absorbance measurements in the visible range. It has been found that the forbidden energy band gap values of the films decrease with increasing pH values and change between 2.42-2.38 eV. The transmission efficiency of CdS films were exhibit about between 84%-65% in the visible region. The surface properties and roughness values of the films were determined using atomic force microscopy. FESEM images show that the films are generally homogeneous distribution in spherical structure.The elemental composition of the films was determined from the EDX study

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