Alignment nature of ZnO nanowires grown on polished and nanoscale etched lithium niobate surface through self-seeding thermal evaporation method

•ZnO nanowires were grown directly on LiNbO3 surface for the first time by thermal evaporation.•Self-alignment of the nanowires due to step bunching of LiNbO3 surface is observed.•Increased roughness in surface defects promoted well-aligned growth of nanowires.•Well-aligned growth was then replicated in 50nm deep trenches on the surface.•Study opens novel pathway for patterned growth of ZnO nanowires on LiNbO3 surface.