Two-step preparation of laser-textured Ni/FTO bilayer composite films with high photoelectric properties

A two-step strategy, i.e. sputtering Ni layers on FTO glass combined with magnetic-field-assisted laser irradiation, was proposed to prepare laser-textured Ni/FTO bilayer composite films. By analyzing surface morphology, crystal structure and photoelectric properties of Ni/FTO films with different Ni layer thicknesses, the Ni/FTO film with a 10-nm-thick Ni layer (Ni10/FTO film), which had the best overall photoelectric property, was chosen to undergo magnetic-field-assisted laser irradiation with different laser fluences. Magnetic-field-free laser irradiation of the Ni10/FTO film was also carried out for comparison purpose. It was found that magnetic-field-assisted laser irradiation using a fluence of 1.0 J/cm2 was more effective for simultaneously achieving texturing and annealing, resulting in formation of ideal grating textures and significantly increased grain size. The corresponding film (MLI-NF1.0 film) showed the highest figure of merit of 22.8 × 10−3 Ω−1 compared to 13.1 × 10−3 Ω−1 of the FTO glass and 1.4 × 10−3 Ω−1 of the Ni10/FTO film, suggesting that the two-step strategy is excellent for preparing textured Ni/FTO films with high photoelectric properties.