Development of AZO TCOs with ALD for HEMT and HJSC Solar Cell Applications

Year 2023, Volume: 26 Issue: 1, 209 - 214, 27.03.2023

Deniz Tugrul , Hüseyin Çakmak , Ekmel Özbay , Bilge İmer

https://doi.org/10.2339/politeknik.873160

Cited By: 1

Abstract

Transparent Conductive Oxide (TCO) films are widely used in optoelectronic devices, such as solar cells, LEDs, and Lasers. Utilization of these contacts directly affects the device efficiencies. Purpose of this study is to produce and optimize properties of Aluminum doped Zinc Oxide (AZO) using a vapor phase technique, Atomic Layer Deposition (ALD) for (n+) a-Si:H surface of silicon Heterojunction Solar Cells (HJSCs) and High Electron Mobility Transistor (HEMT) applications. This study is focused on the effect of the deposition temperature and aluminum atomic concentration on structural, electrical and optical properties of ALD grown AZO ohmic contact films. The results show that as-deposited films have 80-90% transmittance in the visible spectra, low resistance (2.04x10-3 ohm.cm) and mobility value of 5.25 cm2/V.s.

Keywords

Atomic layer deposition (ALD), aluminum doped zinc oxide (AZO), transparent conductive oxide (TCO), non-alloyed ohmic contacts, GaN HEMT contact

AlGaN/GaN Temelli YEMT ve Heteroeklem Güneş Hücreleri Için ALD Yöntemi ile Alüminyum Katkılı Çinko Oksit(AZO) Geliştirme

Abstract

Transparan İletken Oksit (TCO) ince filmler günümüzde güneş pilleri, LED’ler, lazerler gibi optoelektronik cihazlarda sıklıkla kullanılmaktadır. Bu kontakların kullanımı cihazların verimliliğini doğrudam etkilemektedir. Bu çalışmanın amacı heteroeklemli güneş hücrelerinin (HJSCs) (n+) a-Si:H yüzünde ve yüksek elektron hareketliliği olan tranzistörlerde (HEMT) kullanmak üzere atomik katman kaplama (ALD) tekniği kullanarak alüminyum katkılı çinko oksit (AZO) üretmek ve optimize etmektir. Bu çalışmada büyütme sıcaklığı ve alüminyum katkılama oranının ALD’de büyütülmüş AZO’nun yapısal, elektriksel ve optik özelliklerine etkisi çalışılmıştır.Sonuçlar göstermiştir ki filmler görünür bölgede %80-90 arasında ışık geçirgenliğine, düşük elektriksel rezistansa (2.04x10-3 ohm.cm) ve 5.25 cm2/V.s değerinde mobiliteye sahiptir.

Keywords

Atomik katman kaplama (ALD), alüminyum katkılı çinko oksit (AZO), transparan iletken oksitler (TCO), alaşımlanmamış omik kontaklar, GaN HEMT contak

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