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

Yıl 2015, Sayı: 2015 Özel Sayısı, 95 - 108, 15.01.2016

Meryem Polat Gönüllü

Öz

CdS and Mn incorporated CdS:Mn (%10,
%30) films were deposited onto glass substrates at 275+5^oC 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.

Anahtar Kelimeler

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

FARKLI ORANLARDA Mn İÇEREN CdS FİLMLERİNİN BAZI FİZİKSEL ÖZELLİKLERİNİN İNCELENMESİ

Öz

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+5^oC 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

Kaynakça

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