Effect of laser energy on the electrical transport properties of La0.67Ca0.33MnO3:Ag0.2 films by pulsed laser deposition technique

La0.67Ca0.33MnO3 (LCMO):Ag0.2 films were grown on LaAlO3 (LAO) substrates (100) by pulsed laser deposition (PLD) technique with various incident laser energies. The surface morphologies and the thicknesses of the films were studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM), respectively. The crystal structures were analyzed by X-ray, diffraction (XRD), and the temperature dependence of the resistivity (ρ–T) of the films was studied by the standard four-probe method. It can be found that the crystal quality, surface morphology, metal–insulator transition temperature (T p), and temperature coefficient of resistance (TCR) of the LCMO:Ag0.2 films are changed with various laser energy. The highest T p 287 K is obtained with 300 mJ laser energy; meanwhile, the optimal TCR 13.5% K−1 is achieved. The results suggest that the electrical transport properties of LCMO:Ag0.2 films are affected by the interface-induced compressive stress, the oxygen balance, and the double exchange between Mn3+–O–Mn4+.