Morphological and Electrical Properties of Self-Textured Aluminum-Doped Zinc Oxide Films Prepared by Direct Current Magnetron Sputtering for Application to Amorphous Silicon Solar Cells

Abstract

Self-textured Al-doped zinc oxide (AZO) transparent conducting oxide (TCO) layers were grown by DC magnetron sputtering, and their morphological and electrical properties were investigated. The self-textured AZO layers were fabricated by controlling the deposition conditions, without employing wet or dry etching for surface texturing. The polycrystalline AZO layers with a high surface roughness (42 nm) were grown on a glass substrate at various DC plasma power. The lowest sheet resistance was 3.7×10-4 Ω cm and the highest carrier mobility obtained was 30 cm2 V-1 s-1, which are comparable to those of chemically textured AZO layers. The electrical and optical characteristics of the self-textured AZO films are comparable to those of wet-etched AZO films that were etched using the conventional HCl solution. Our study suggests a possible way to inexpensively fabricate amorphous silicon thin-film solar cells.