Properties of ITO Ceramics and Thin Films Prepared by Sputtering Process

摘要

Indium-tin oxide (ITO) films are widely used in optical electronic devices, such as flat panel displays, solar cells and some others, due to their high electrical conductivity and transparency. They are prepared by different deposition methods, e.g. by DC magnetron sputtering processes using ITO ceramic sputtering targets. The requirements for these ceramics are very high; they include high purity, high density (up to 99+% of TD) and high electrical conductivity, and the ceramics and sputtering process should provide a formation of nano-crystalline or amorphous electrically conductive transparent films without structural defects. Microstructure and physical properties, such as specific electrical resistivity, ultrasonic, mechanical and thermophysical characteristics, of the ITO ceramics commercially manufactured by Umicore Indium Products (UIP) have been studied. Structure and properties of the films prepared using a DC magnetron sputtering system have been analyzed. Due to the optimized parameters of the sputtering process and the use of high quality ceramics, a formation of highly conductive and transparent thin films (with transmittance of 90% or even greater at the 550nm wavelength) have been obtained. These results have been achieved for the ITO films sputtered using large ceramic tiles with areas up to 1200-1700cm{sub}2.