Thermophysical properties of SnO₂-based transparent conductive films: Effect of dopant species and structure compared with In₂O ₃-, ZnO-, and TiO₂-based films

We investigate the effect of dopant species and structure on the thermal conductivity of Sb-doped Sn₂ (ATO) and Ta-doped Sn₂ (TTO) films and compare the results with those of In₂O₃-, ZnO-, and TiO₂-based transparent conductive films. The thermal conductivities (λ) of polycrystalline ATO and TTO films are 4.4-4.9 and 4.7 W m^-1 K^-1, respectively. The thermal conductivities via phonons (kph) are almost identical for both dopant species (Sb and Ta): 4.3 and 4.5Wm^-1 K^-1 for Sb and Ta, respectively, on average. These results for λ_ph are larger than that for Sn-doped In₂O₃ films (3.8 W m^-1 K^-1) and considerably larger than that for amorphous ATO films (1.0 W m^-1 K^-1). These facts lead us to conclude that the base-material species (Sn₂ or In₂O₃) and structure (polycrystalline or amorphous) affect the thermophysical properties of ATO and TTO much more than the dopant species.