Effect of low temperature anneal on the optical and electrical properties of Cu/GZO double layers

Abstract

Double layer Cu/GZO system was prepared at room temperature by magnetron sputtering. Electrical properties are greatly improved, while the crystal structure of GZO is deteriorated by the Cu layer; even when its thickness is only 5 nm. Furthermore, effect of thermal annealing on the optical and electrical properties has been investigated. Transmittance of Cu/GZO in the long wavelength shows an increase for the films annealed at 200 °C and below. A low resistivity of about 7.5 × 10−4 Ω cm for the Cu/GZO with a thickness of Cu 5 nm is found to be retained until 125 °C, followed by a slow increase as the temperature further increases, which is considered to be due to a significant change in the morphology of the Cu layer which is revealed by high resolution TEM observation. It is found that good optical and electrical properties of the Cu/GZO double layer system can be obtained simultaneously by optimizing annealing parameters.