Optical and electrical characteristics of Al-doped ZnO thin films prepared by aqueous phase deposition

Pin Chuan Yao, Shih Tse Hang, Yu Shuan Lin, Wen Tsai Yen, Yi-Cheng or Y. C. Lin

Research output: Contribution to journalArticlepeer-review

53 Citations (Scopus)


Transparent conducting Al-doped ZnO (AZO) thin films have been deposited by sol-gel route. Starting from an aqueous solution of zinc acetate by adding aluminum chloride as dopant, a c-axis oriented polycrystalline ZnO thin film 100 nm in thickness could be spin-coated on glass substrates via a two-step annealing process under reducing atmosphere. The effects of thermal annealing and dopant concentration on the structural, electrical and optical properties of AZO thin films were investigated. The post-treated AZO films exhibited a homogenous dense microstructure with grain sizes less than 10 nm as characterized by SEM photographs. The annealing atmosphere has prominent impact on the crystallinity of the films which will in turn influence the electrical conductivity. By varying the doping concentrations, the optical and electrical properties could be further adjusted. An optimal doping concentration of Al/Zn = 2.25 at.% was obtained with minimum resistivity of 9.90 × 10 -3 Ω-cm whereas the carrier concentration and mobility was 1.25 × 10 20 cm -3 and 5.04 cm 2 V -1 s -1 , respectively. In this case, the optical transmittance in the visible region is over 90%.

Original languageEnglish
Pages (from-to)1441-1448
Number of pages8
JournalApplied Surface Science
Issue number5
Publication statusPublished - 2010 Dec 15

All Science Journal Classification (ASJC) codes

  • Surfaces, Coatings and Films

Fingerprint Dive into the research topics of 'Optical and electrical characteristics of Al-doped ZnO thin films prepared by aqueous phase deposition'. Together they form a unique fingerprint.

Cite this