Effect of TiO2 lowermost layer on crystal orientation and electrical resistivity of glass/TiO2/ZnO/Ag structure in Low-E glass

Abstract

Abstract In order to improve the heat insulating properties of low-emissivity coatings, it is necessary to reduce the electrical resistivity of their multilayer structure, which consists of an Ag layer and oxide layers. In this study, structures comprising glass/ZnO/Ag and glass/TiO2/ZnO/Ag were deposited by sputtering, and the effects of these layers on the electrical resistivity were investigated. For a ZnO layer deposited at low sputtering gas pressure, lower surface roughness reduced the electrical resistivity of the Ag layer. Also, it was found that the electrical resistivity could be further decreased by inserting a TiO2 lowermost layer between the substrate and the ZnO layer. The results of X-ray diffraction and X-ray reflectivity measurements showed that the decrease in resistivity was mainly due to the improved crystal orientation of the ZnO and Ag layers.