Flash light sintering of ag mesh films for printed transparent conducting electrode

Abstract

Transparent conducting electrodes (TCEs) are fabricated through the flash light sintering of reverse-offset printed Ag mesh patterns. Interestingly, the narrower printing lines require a higher flash light energy to obtain an equivalent sheet resistance even if the same Ag nanoparticle ink is used. The microstructural development of sintered Ag nanoparticles is also retarded with the decrease of line width after the same flash light sintering. The temperature calculation in the Ag mesh patterns clearly reveals that heat dissipation is affected by the print dimension. To improve the performance of Ag mesh TCEs with 3μm wide lines, a preheating step comprised of multi-pulses is inserted before a main flash light sintering. The multi-pulsed flash light sintering is effective in decreasing the sample temperature and in removing the substrate damages or microstructural defects. As a result, the flash light-sintered Ag mesh TCEs shows a sheet resistance of 27Ω/□ and an optical transmittance of 84.7% including an optical transmittance of substrate.