Nanostructure evolution of YBa2Cu3Ox thin films grown by pulsed-laser glancing-angle deposition

Nanostructured thin films of amorphous YBa2Cu3Ox were prepared using pulsed-laser glancing-angle deposition. Ambient oxygen pressure and laser fluence have a strong effect on the microstructure of the films. The films exhibit a structural evolution from isolated directional nanorods, through a network of vertical nanocolumns, to nanoparticles fractal with increasing ambient oxygen pressures from below 1 to above 180mtorr. The shadowing effect, surface diffusion, and flux scattering by ambient gas play main roles in determining the structural evolution.