INFLUENCE OF SULFURIZATION ON THE PROPERTIES OF Cu2ZnSnS4 (CZTS) THIN FILMS PREPARED BY A TWO-STAGE PROCESS

Yıl 2019, , 1064 - 1072, 31.07.2019

Mehmet Ali Olğar

https://doi.org/10.28948/ngumuh.598096

Öz

   In this
study, CZTS thin films were grown by a two-stage method involved sputter
deposition of metallic Cu, Zn, and Sn layers to form Cu/Sn/Zn/Cu metallic
stacks on glass and sulfurization of the metallic stacks at 540 and 580 °C for
1 and 5 min in sulfur vapor atmosphere. The reacted samples at two different
sulfurization temperatures and sulfurization times were characterized employing
XRD, SEM, EDX, Raman spectroscopy, optical spectroscopy, and Van der Pauw
methods. The metallic stacks and CZTS thin films showed Cu-rich and Zn-poor
composition. XRD patterns of the reacted films showed almost pure kesterite
CZTS phase except for presence of very small amount of Cu_2-xS phase.
Raman spectra of the films verified formation of kesterite phase in the films.
SEM images showed that the CZTS540-1 sample had more compact, denser and
uniform structure. Optical band gap values were found to be in good agreement
with the literature. The CZTS540-1 thin film showed the highest carrier
concentration and lowest resistivity values amongst the other samples.

Anahtar Kelimeler

CZTS, Sputtering, Sulfurization Time, Temperature, Two-stage Method

Teşekkür

I am gratefully acknowledge the help of B.M. Basol and E. Bacaksiz for discussion, M. Tomakin for EDX, XRD, and SEM measurements.

İKİ AŞAMALI YÖNTEM İLE HAZIRLANAN Cu2ZnSnS4 (CZTS) İNCE FİLMLERİN ÖZELLİKLERİNDE SÜLFÜRLEMENİN ETKİSİ

Öz

   Bu çalışmada CZTS ince filmler; Cu, Zn ve Sn
metalik katmanların saçtırma yöntemi ile Cu/Sn/Zn/Cu yapılarının  cam üzerine kaplanması ve bu yapıların 540 ve
580 °C sıcaklıkta 1 ve 5 dakika sürelerince sulfur atmosferinde sülfürlenmesi
şeklinde iki-aşamalı metot kullanılarak büyütülmüştür. Değişik sıcaklık ve
sürelerde sülfürlenen örnekler XRD, SEM, EDX, Raman spektroskopisi, Optik spektroskopi
ve Van der Pauw yöntemleri kullanılarak karakterize edilmiştir. Tabakalı
metalik yapı (Cu/Sn/Zn/Cu) ve CZTS örneklerinin Cu-zengini ve Zn-fakiri
kompozisyona sahip olduğu gözlemlendi. Üretilen CZTS ince filmlerin XRD
verileri incelediğinde, çok az Cu_2-xS fazı dışında neredeyse saf
CZTS yapısına sahip kırınım deseni gösterdiği görülmüştür. Raman spektroskopisi
kullanılarak CZTS fazının oluştuğu teyit edilmiştir. SEM görüntüleri
incelendiğinde, CZTS540-1 örneğinin daha kompakt, yoğun ve homojen bir yapıya
sahip olduğu gözlemlenmiştir. Elde edilen optik yasak enerji aralıklarının
literatür ile uyum içinde olduğu görülmüştür. Elektriksel ölçümler, CZTS540-1
ince filminin en yüksek taşıyıcı yoğunluğuna ve en düşük özdirenç değerlerine
sahip olduğunu göstermiştir.

 

Anahtar Kelimeler

CZTS, Saçtırma, Sülfürleme Süresi, Sülfürleme Sıcaklığı, Iki-aşamalı Metot

Kaynakça

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