ANNEALING TEMPERATURE EFFECTS ON SURFACE MORPHOLOGY AND OPTICAL PROPERTIES OF IGZO THIN FILMS PRODUCED BY THERMAL EVAPORATION

Year 2020, Volume: 16 Issue: 1, 25 - 44, 29.04.2020

Atilgan Altınkök , Murat Olutaş

Abstract

The use of Transparent Conductive Oxide (TCO) thin films in technology has increased in the last decades. These materials have good electrical conductivity visible light transmittance simultaneously. TCOs have many technology applications such as thin film transducers (TFTs), conductive electrodes, capacitors, sensors, electrochemical devices. Although indium tin oxide (ITO) is the most widely used material among these materials, studies on N-type indium-gallium-zinc oxide (IGZO) that better electrical properties (electron mobility µFE>10 cm2 /V.s) cm2 / Vs) have increased in recent years. In this study, IGZO thin films are produced which have a very homogeneous amorphous structure at room temperature under high vacuum by using thermal evaporation system on glass substrates. Structural characterization was carried out by scanning electron microscopy, atomic force microscopy, on IGZO thin films for various thickness and annealing temperatures. Transmittance and thickness measurements were performed using UV-VIS spectroscopy and profilometer for the investigation of optical properties, respectively. It is seen that grain size grows and grain boundaries decreases when annealing temperature is increased. This results in reduced roughness and increased optical transmittance and energy gap (Eg).

Keywords

IGZO, AFM, Thin film, Band Energy

Supporting Institution

Giresun University Scientific Research Fund

Project Number

FEN-BAP-A-230218-26

TAVLAMA SICAKLIĞININ TERMAL BUHARLAŞTIRMA İLE ÜRETİLEN IGZO İNCE FİLMLERDE YÜZEY MORFOLOJİSİ VE OPTİK ÖZELLİKLERE ETKİSİ

Abstract

Saydam
İletken Oksit (TCO) ince filmlerin teknolojide kullanımı son yıllarda artmıştır.
Bu
malzemeler aynı anda iyi bir elektrik iletkenliğine ve görünür ışık
geçirgenliğine sahiptir. TCO'lar, ince film dönüştürücüler (TFT'ler), iletken
elektrotlar, kapasitörler, sensörler, elektrokimyasal cihazlar gibi birçok
teknoloji uygulamasında kullanılmaktadırlar. İndiyum kalay oksit (ITO) bu
malzemeler arasında en yaygın kullanılan malzeme olmasına rağmen, daha iyi
elektriksel özelliklere (elektron hareketliliği µFE>10 cm² /V.s)
cm² / Vs) sahip olan N tipi indiyum-galyum-çinko oksit (IGZO)
üzerinde yapılan çalışmalar günümüzde önem kazanmıştır. Bu çalışmada, cam alttaş üzerinde termal
buharlaştırma sistemi kullanılarak yüksek vakum altında oda sıcaklığında çok
homojen bir amorf yapıya sahip IGZO ince filmler üretilmiştir. Üretilen IGZO
ince filmlerin yapısal karakterizasyonu ise Atomik kuvvet mikroskobu ve
taramalı elektron mikroskobu kullanılarak  çeşitli kalınlık ve tavlama sıcaklıkları için
gerçekleştirilmiştir. Geçirgenlik ve
kalınlık ölçümleri ise optik özelliklerin araştırılması için sırasıyla UV-VIS
spektroskopisi ve profilometre kullanılarak yapılmıştır. Tavlama sıcaklığı arttıkça tanecik boyutunun
büyüdüğü ve tane sınırlarının azaldığı görülmektedir. Bu durum, pürüzlülüğün azalmasına ve optik geçirgenliğin ve enerji boşluğunun
(E_g) artmasına neden olmaktadır.

Keywords

IGZO, AFM, İnce Film, Band Enerjisi

Project Number

FEN-BAP-A-230218-26

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