Ni/FTO bilayer thin films with high photoelectric properties optimized by magnetic-field-assisted laser annealing

• Ni/FTO films were laser annealed without/in vertical and transverse magnetic filed.
• Magnetic laser annealing greatly increased grain size and improved film quality.
• The films annealed in different magnetic field had different surface morphologies.
• The film annealed in transverse magnetic field had the best photoelectric property.
• This work may provide a new idea for performance optimization of metal/FTO films.

The photoelectric properties of nickel (Ni)/fluorine-doped tin oxide (FTO) bilayer films were optimized by magnetic-field-assisted laser annealing using a 532 nm nanosecond pulsed laser. Laser annealing without a magnetic field was also performed for comparison purpose. Magnetic-field-assisted laser annealing can greatly promote grain growth and increase grain size in the films, thereby effectively enhance transmittance and reduce sheet resistance. Interestingly, after being laser annealed in a vertical magnetic field, the film surface was covered with sparsely distributed and agglomerated grains, resulting in relative low conductivity. In contrast, the surface of the film which was laser annealed in a transverse magnetic field exhibited densely and uniformly distributed grains, and thus had the highest transmittance and lowest sheet resistance. This work may provide a new idea for performance optimization of metal/FTO bilayer films.