Thermally stable transparent conducting and highly infrared reflective Ga-doped ZnO thin films by metal organic chemical vapor deposition

Highly transparent conductive Ga-doped ZnO (GZO) thin films have been prepared on glass substrates by metal organic chemical vapor deposition. The effect of Ga doping on the structural, electrical and optical properties of GZO films has been systematically investigated. Under the optimum Ga doping concentration (∼4.9 at.%), c-axis textured GZO film with the lowest resistivity of 3.6 × 10−4 Ω cm and high visible transmittance of 90% has been achieved. The film also exhibits low transmittance (<1% at 2500 nm) and high reflectance (>70% at 2500 nm) to the infrared radiation. Furthermore, our developed GZO thin film can well retain the highly transparent conductive performance in oxidation ambient at elevated temperature (up to 500 °C).

Research highlights
► High thermal stability was achieved in the transparent conductive Ga:ZnO thin films by MOCVD.
► The effect of Ga doping on the physical properties of GZO films was systematically investigated.
► The resistivity is lower than most of the previous ZnO based TCO films by MOCVD.
► GZO films exhibit high reflectance to the IR radiation, which is useful for energy-saving windows.