Investigation of the Structural Properties and Electrical Responses of AZO Thin Films Deposited on Cotton Yarns

Abstract

The development of functional textiles has gained increasing attention due to their potential applications in wearable electronics and sensor technologies. In this study, Al-doped ZnO (AZO) thin film coatings were deposited onto cotton yarns using the sol–gel dip-coating method. In addition to undoped ZnO coatings, two different AZO samples were prepared by adjusting the Al precursor content to 2 wt.% and 4 wt.% in the precursor solution. The morphological characteristics of the coatings were investigated by scanning electron microscopy (SEM), while their electrical responses were evaluated using an analog-to-digital converter microcontroller board-based measurement system. SEM analyses revealed that undoped ZnO coatings exhibited a more homogeneous and continuous surface morphology, whereas increasing Al doping led to enhanced surface roughness, agglomeration, and film discontinuities. Electrical measurements indicated that undoped ZnO samples showed stable but low electrical responses, while higher Al doping levels adversely affected electrical stability due to structural inhomogeneities. The results demonstrate that, for AZO thin films deposited on textile substrates under low-temperature processing conditions, surface uniformity and film continuity play a critical role in determining electrical behavior.

Keywords

• Thin film
• Nanomaterial
• Cotton substrate
• Sol-gel
• Characterization
• Electrical properties

Pamuk İplikler Üzerine Biriktirilen AZO İnce Filmlerin Yapısal Özellikleri ve Elektriksel Yanıtlarının İncelenmesi

Abstract

Fonksiyonel tekstillerin geliştirilmesi, giyilebilir elektronik ve sensör teknolojilerindeki potansiyel uygulamaları nedeniyle giderek artan bir ilgi görmektedir. Bu çalışmada, Al katkılı ZnO (AZO) ince film kaplamaları, sol-jel daldırma kaplama yöntemi kullanılarak pamuk ipliklerine uygulanmıştır. Katkısız ZnO kaplamalarına ek olarak, öncü çözeltideki Al öncü içeriği %2 ve %4 olacak şekilde ayarlanarak iki farklı AZO numunesi hazırlanmıştır. Kaplamaların morfolojik özellikleri taramalı elektron mikroskobu (SEM) ile incelenirken, elektriksel tepkileri analog-dijital dönüştürücü mikrokontrolör kart tabanlı bir ölçüm sistemi kullanılarak değerlendirilmiştir. SEM analizleri, katkısız ZnO kaplamalarının daha homojen ve sürekli bir yüzey morfolojisi sergilediğini, Al katkısının artmasının ise yüzey pürüzlülüğünü, kümelenmeyi ve film süreksizliklerini artırdığını ortaya koymuştur. Elektriksel ölçümler, katkısız ZnO numunelerinin kararlı ancak düşük elektriksel tepkiler gösterdiğini, daha yüksek Al katkılama seviyelerinin ise yapısal homojen olmama nedeniyle elektriksel kararlılığı olumsuz etkilediğini göstermiştir. Sonuçlar, düşük sıcaklık işleme koşulları altında tekstil alt tabakalara biriktirilen AZO ince filmler için yüzey düzgünlüğünün ve film sürekliliğinin elektriksel davranışı belirlemede kritik bir rol oynadığını göstermektedir.

Keywords

• İnce film
• Nanomalzeme
• Pamuk altlık
• Sol-gel
• Karakterizasyon
• Elektriksel özellik

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