Hexagonal nanopatterns were fabricated in sputter deposited Al-oxide thin films by means of single UV laser pulses via a layer of self-assembled silica nanospheres. The hexagonal pattern was projected to the surface due to the focussing effect of the silica nanolenses enhancing the local impact of the pulse. As a result of the laser pulse large area ordered structure of nano-pits were formed in RF sputtered amorphous Al-oxide films, while nano-craters were created in DC sputter deposited layers that consist of Al nanocrystals embedded in amorphous matrix. The two different mechanisms governing the nanostructure formation in the a-AlOx and nc-Al/AlOx composite layers were revealed by Atomic Force Microscopy (AFM), cross-sectional Transmission Electron Microscopy (XTEM), spectroscopic ellipsometry and computer simulation. Abstract Hexagonal nanopatterns were fabricated in sputter deposited Al-oxide thin films by means of single UV laser pulses via a layer of self-assembled silica nanospheres. The hexagonal pattern was projected to the surface due to the focussing effect of the silica nanolenses enhancing the local impact of the pulse. As a result of the laser pulse large area ordered structure of nano-pits were formed in RF sputtered amorphous Al-oxide films, while nano-craters were created in DC sputter deposited layers that consist of Al nanocrystals embedded in amorphous matrix. The two different mechanisms governing the nanostructure formation in the a-AlO x and nc-Al/AlO x composite layers were revealed by Atomic Force Microscopy (AFM), cross-sectional Transmission Electron Microscopy (XTEM), spectroscopic ellipsometry and computer simulation.