FARKLI ORANLARDA Mn İÇEREN CdS FİLMLERİNİN BAZI FİZİKSEL ÖZELLİKLERİNİN İNCELENMESİ

CdS ve farklı oranlarda (%10, %30) mangan (Mn) katılmış CdS:Mn filmleri uygulaması kolay ve ekonomik olmasıyla dikkat çeken ultrasonik kimyasal püskürtme (UKP) yöntemi ile 275+5oC taban sıcaklığında üretilmiş ve 3 saat süreyle 500°C sıcaklıkta tavlama işlemine tabi tutulmuştur. Tüm filmlerin fotovoltaik güneş hücrelerinde kullanım potansiyelini araştırmak amacıyla optik, elektrik ve yüzey özellikleri incelenmiştir. Elde edilen filmlerin kalınlıkları ve bazı optik özelliklerinin belirlenmesi için Spektroskopik Elipsometri (SE) ve UV/VIS Spektroskopi teknikleri kullanılmıştır. Optik metot kullanılarak ham ve Mn katılmış CdS:Mn filmlerin optik bant aralıkları sırası ile 2.14 eV, 2,24eV ve 2.16 eV olarak belirlenmiştir. Elde edilen filmlerin kırılma indisi değerlerinin 1.73-1.80 aralığında değiştiği ve sönüm katsayısı değerlerinin ise 0.10 civarında sabit kaldığı saptanmıştır. Yüzey morfolojileri ve yüzey pürüzlülük değerleri atomik kuvvet mikroskobu kullanılarak incelenmiş ve dört uç metodu ile CdS ve CdS:Mn filmlerinin elektriksel özdirençlerinin 5.5×104 - 4.8×105 Wcm aralığında değiştiği belirlenmiştir.

Anahtar Kelimeler:

Ultrasonik Kimyasal Püskürtme, CdS, Mn, Spektroskopik Elipsometre, Atomik Kuvvet Mikroskobu

INVESTIGATION OF SOME PHYSICAL PROPERTIES OF CdS FILMS AT DIFFERENT Mn INCORPORATION

CdS and Mn incorporated CdS:Mn (%10, %30) films were deposited onto glass substrates at 275+5oC by a low cost and simple ultrasonic spray pyrolysis technique and annealed at 500°C during 3 hours at air atmosphere. Optical, electrical and surface properties of the films were investigated in order to determine of application potential on photovoltaic solar cells. Spectroscopic Ellipsometry and UV/VIS spectrophotometry techniques were used to determine of film thicknesses and some optical properties. Band gaps of CdS and CdS:Mn films were identified using optical method as 2.14 eV, 2,24eV and 2.16 eV, respectively. It was determined that the refractive indices values of the films changed between 1.73-1.80 and extinction coefficient values remain constant around 0.10. Surface morphologies and roughness values of the films were investigated by Atomic Force Microscopy. Also, electrical resistivities of all films determined by four point probe technique between 5.5×104 - 4.8×105 Wcm.

Keywords:

Ultrasonic Spray Pyrolysis, CdS, Mn, Spectroscopic Ellipsometry, Atomic Force Microscopy,

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