Scanning Probe Microscopy Investigation of H-irradiated ZnO and Co-doped ZnO thin films in dark and UV-light conditions

We studied the effect of hydrogen irradiation on ZnO and Co-doped ZnO thin films, discussing the induced multiferroicity and the change of the electronic response to the UV-lighting. Pure and Co-doped thin films were grown by pulsed laser deposition technique on Ag coated Si(p-type) substrate, giving rise to a ZnO/Ag/Si heterostructures, followed by post-growth hydrogenation at temperatures as high as 400 $^{\circ}$ C. In particular, the electronic properties have been probed by light-assisted Scanning Probe Microscopy experiments whereas the magnetic properties have been investigated by Hall transport and magnetization loop measurements. The effect of Co-doping on the electronic density of stases has been also considered.