Possibilities of Increasing the Usability of Sputtered AZO Films as a Transparent Electrode

• Published in: Physica status solidi. A, Applications and materials science Vol. 216; no. 7
• Main Author: Novák, Petr
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 10.04.2019
• Subjects: Aluminum; aluminum‐doped zinc oxide; Electrical properties; Electrodes; Indium tin oxides; magnetron sputtering; Photovoltaic cells; Solar cells; Substrates; Thickness; thin film; transparent conductive oxides; Usability; Zinc oxide
• ISSN: 1862-6300; 1862-6319
• DOI: 10.1002/pssa.201800814

Aluminum‐doped zinc oxide (AZO) is a suitable material for use as transparent electrode. Due to its lower price it is applied in the production of silicon solar cells. However, it is difficult to obtain suitable electrical properties at low deposition temperatures. Moreover, the AZO films with low thickness exhibit significantly higher average resistivity, which limits their usability, especially if they are prepared on flexible substrates. A lot of effort is invested to replace indium tin oxide (ITO) to a much greater extent now, since Indium is rare and its price is rising, thus the preparation of low‐thickness AZO films at low temperature is also subject of intense research. The presented paper summarizes the reported results, discusses the causes of the differences between ITO and AZO films, and suggests the direction of research and the potential solution that should lead to increased usability of AZO films and also possible replacement of ITO films. This paper reviews the influence of deposition parameters on the electrical properties of aluminum doped zinc oxide, which is cheap and non‐toxic transparent conductive material, but its usability is limited due to higher resistivity of low thickness ZnO films prepared at low temperature. The main reasons are discussed and the potential solutions to improve the electrical properties are proposed.