Zinc oxide structures with size in the micro and nano-scale range represent key candidates for developing novel, cheap and efficient electronic devices, power generators and sensors based on the cooperative response of a large number of synced structures. The accurate electrical characterization of single ZnO micro/nanostructures is thus critical for assessing and optimizing the device performance and reliability, and requires the use of metallic scanning nano-probes for establishing electrical contact with the nano-structures. We report on the characterization of the contact resistance between AFM conductive tip and a selection of metallic layers to be used as top metallic coating allowing for nano-electrical characterization of FIB machined ZnO micro/nanopillars. Our findings show that the use of an Au film on top of Ti ohmic contact layer is crucial for reliable conductive AFM investigation of single isolated ZnO …