Resistance and transparency tunable Ag-inserted transparent InZnO films for capacitive touch screen panels

Abstract

We have investigated sheet resistance and transparency tunable Zn-doped In2O3 (IZO) films through the insertion of a nano-size Ag layer for use as transparent electrodes for capacitive-type touch screen panels (TSPs). Due to the high conductivity of a nano-size Ag layer, the optimized IZO/Ag/IZO film showed the lowest resistivity of 3.69×10−5Ω-cm, even though it was sputtered at room temperature. The dependence of resistivity on temperature demonstrated that the electrical conductivity of the IZO/Ag/IZO is dominated by the nano-sized Ag metal layer. Furthermore, effective antireflection of the IZO/Ag/IZO at optimized Ag thickness (14nm) led to high optical transmittance of 85.16%, which is higher than that of conventional ITO films. Using optimized IZO/Ag/IZO with a sheet resistance of 5.27Ω/sq and an optical transmittance of 85.16% prepared on specially designed flexible substrate (Nepes glasslike film), we demonstrated capacitive TSPs. The operation of capacitive-type TSPs with IZO/Ag/IZO multilayer electrodes indicates that the IZO/Ag/IZO multilayer is a promising transparent electrode for large-area capacitive-type TSPs due to its low sheet resistance and high transparency when it is very thin.