A facile method to decrease surface roughness of fluorine doped tin oxide using nanoparticles in toothpaste and its application in hybrid light emitting diode

In this report a facile and optimized method for polishing of fluorine doped tin oxide (FTO) was presented in which nanoparticles in toothpaste was used as polishing material. Due to being more chemically and physically stability relative to another TCO such as indium tin oxide (ITO), FTO is used in optoelectronic devices. More thickness in FTO due to have a good conductivity resulting a rough surface. Toothpaste can make smooth FTO surface due to have polisher nanoparticles. Here, FTO surface was smooth using toothpaste so that according to AFM data, the RMS surface roughness was changed from 12 nm for FTO to 3 nm for FTO after polishing. The comparing of the transmittance spectra FTO before and after polishing process showed the FTO thickness was not changed dramatically. The X-Ray photoelectron spectroscopy showed there were no effects on the chemical states of FTO surface before and after polishing process. The hybrid light emitting diode was fabricated using polished FTO that it was more efficient comparing to those fabricated with FTO and ITO.