We report on the fabrication of Schottky diodes based on n-type zinc oxide (ZnO) grown by atomic layer deposition (ALD) at low temperature (100 °C). These structures are suitable as selector elements in highly integrated non volatile memories based on crossbar architecture. The junctions are fully realized by optical lithography and the smallest investigated structures are 3 × 3 μm2 area. Several metals have been tested to single out the most suitable ohmic and Schottky contact materials. The electrical characterisation shows good properties with a forward current above 104 A/cm2 and a rectifying ratio of 105.