Effect of the heat treatment on the infrared emissivity of indium tin oxide (ITO) films

► Direct current magnetron sputtering was adapted to prepare the 600 nm ITO films under different substrate temperatures. ► The mean infrared emissivity was measured in the heat-treatment process of heating and cooling from room temperature to 350 °C. ► Effect of the heat treatment on the infrared emissivity of indium tin oxide (ITO) films was investigated in detail. ► The emissivities of all films are below 0.3 in the whole heat treatment process.