Effect of Annealing Process on Optical, Electrical and Surface Properties of ZnO films

Abstract

ZnO films were prepared on glass at 3005 C substrate temperature by ultrasonic spray pyrolysis. The deposited films were annealed at various temperatures (350, 450, 550 C) for 2 hours. Annealed and unannealed of ZnO films were characterized by studying their optical, electrical and surface properties. The optical transmittance and absorbance spectra of all films were examined by UV-VIS Spectrophotometer and the optical band gap was found using optic method. Besides, visible emission peaks and native point defects of ZnO films were determinate using photoluminescence spectra. Thickness, refractive index and extinction coefficient values were obtained with spectroscopic ellipsometry technique. The electrical and surface properties of the films were characterized four point technique and atomic force microscopy, respectively. According to result, the effects of annealing temperature on the optical, electrical and surface properties of the ZnO films are discussed

Keywords

• ZnO films
• Photoluminescence
• Spectroscopic Ellipsometry
• Four Point Technique
• Atomic Force Microscopy

ZnO Filmlerinin Optik, Elektrik ve Yüzey Özellikleri Üzerine Tavlama İşleminin Etkileri

Abstract

ZnO filmleri 3005 ï‚°C sıcaklıktaki cam tabanlar üzerine ultrasonik kimyasal püskürtme tekniği kullanılarak hazırlanmıştır. Depolanan filmler çeşitli sıcaklıklarda (350, 450, 550 ï‚°C) 2 saat süre ile tavlanmıştır. Tavlanmış ve tavlanmamış ZnO filmlerinin elektrik, optik ve yüzey özellikleri incelenmiştir. Tüm filmlerin optik geçirgenlik ve absorbans spektrumları UV-VIS Spektrofotometre ve optik bant aralıkları da optik metot kullanılarak belirlenmiştir. Ayrıca, ZnO'in görünür emisyon pikleri ve nokta kusurları da fotolüminesans spektrumu kullanılarak belirlenmiştir. Kalınlık, kırılma indisi ve sönüm katsayısı değerleri spektroskopik elipsometre tekniği ile elde edilmiştir. Elektrik ve yüzey özellikleri sırasıyla dört uç tekniği ve atomik kuvvet mikroskobu ile incelenmiştir. Elde edilen sonuçlara göre ZnO filmlerinin optik, elektrik ve yüzey özellikleri üzerine tavlama sıcaklığının etkisi araştırılmıştır.

Keywords

• Gövde
• Isı değiştiricisi
• Basınç düşümü
• Enerji

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