공학
한국표면공학회지 (51권2호 116-125)
Electrical, Optical, and Electrochemical Corrosion Resistance Properties of Aluminum-Doped Zinc Oxide Films Depending on the Hydrogen Content
Cho, Soo-Ho;Kim, Sung-Joon;Jeong, Woo-Jun;Kim, Sang-Ho;
Department of Energy, materials and Chemical Engineering, Korea University of Technology and Education;
DOI : 10.5695/JKISE.2018.51.2.116
Abstract
Aluminum-doped zinc oxide (AZO) is a commonly used material for the front contact layer of chalcopyrite $CuInGaSe_2$ (CIGS) based thin film solar cells since it satisfies the requisite optical and electrical properties with low cost and abundant elemental availability. Low-resistivity and high-transmission front contacts have been developed for high-performance CIGS solar cells, and nearly meet the required performance. However, the durability of the cell especially for the corrosion resistance of AZO films has not been studied intensively. In this work, AZO films were prepared on Corning glass 7059 substrates by radio frequency magnetron sputtering depending on the hydrogen content. The electrical and optical properties and electrochemical corrosion resistance of the AZO films were evaluated as a function of the hydrogen content. With increasing hydrogen content to 6 wt%, the crystallinity, crystal size, and surface roughness of the films increased, and the resistivity decreased with increased carrier concentration, Hall mobility, oxygen vacancies, and $Zn(OH)_2$ binding on the AZO surface. At a hydrogen content of 6 wt%, the corrosion resistance was also relatively high with less columnar morphology, shallow pore channels, and lower grain boundary angles.
Keywords
Aluminum-doped zinc oxide;Radio frequency magnetron sputtering;Thin films;Transparent conductive oxide;Polarization test;