Solution-based synthesis and deposition of transparent conducting aluminium doped zinc oxide

Abstract

Aluminium doped zinc oxide (AZO) has attracted significant attention for replacing ITO. In the current work two approaches are presented for the wet-chemical processing of AZO.

Chemical solution deposition of aluminium doped zinc oxide, by spin coating a 2-butoxyethanol precursor, yields TCO coatings with a transparency higher than 90 % and a resistivity of 1.3 mOhm cm after annealing in a reducing atmosphere. Furthermore, the potential of this precursor for large area coatings is demonstrated, by transferring the precursor to a spray coating system.

Next, different synthesis routes for AZO nanoparticles are presented leading to particles with various characteristics. Minor modifications of the synthesis conditions have a profound impact in the particle morphology, the crystallographic position of the aluminium dopant and the generation of free charge carriers. Through an in-depth study of their characteristics, the most promising particles can be selected. Also, their potential as building blocks for transparent conducting coatings is demonstrated, providing a resistivity of 9.4 mOhm cm.

In this work we demonstrate that through in-depth characterization we can correlate the synthesis conditions to the intrinsic properties of the obtained oxide, and come to functional, solution deposited TCO coatings.