Preparation of sol-gel ZrO₂ films with high laser-induced damage threshold under high temperature

In this study, three different types of ZrO₂ films were prepared with different precursors and additives using the sol-gel method. High-temperature annealing was implemented to investigate the impact of temperature on optical properties, microstructure, surface morphologies and absorption of these films. According to the laser-induced damage threshold (LIDT) tests on films having experienced annealing and those implemented with in-situ high temperature, the ZrO₂ film with ZrOCl₂·8H₂O as the precursor and copolymer of silicone and polyaldoxyl ether as the additive had the highest resistance to laser-induced damage. After annealing at 623 K, its LIDT was 21.4 J/cm², while that at an in-situ high temperature of 523 K was 23.9 J/cm². The strong high temperature resistance was likely attributed to the usage of carbon-free precursor and high temperature-resistant additive, which contributed to low carbon contents and less structural damage caused by organic matter evaporation. In this context, there were less high temperature-induced impurity and structural defects, leading to higher LIDT values. This study provided a novel method for preparing high temperature-resistant sol-gel films, which shed light upon wider potential application of sol-gel films at high-temperature conditions.