ZnO is a promising wide bandgap semiconductor for optoelectronic applications in blue lasers and LEDs. In this project, high performance Schottky diodes are fabricated on ZnO in a collaboration with the University of Canterbury (New Zealand) will be used as test structures for studies related to deep levels in ZnO. Ion implantation will be used to selectively introduce minute amounts of point defects and understand their nature. Deep level transient spectroscopy (DLTS) will be carried out to identify electrical active point defects and the nature and origin of these defects. Additional electrical characterisation techniques such as thermal admittance spectroscopy (TAS) and variable field and variable temperature Hall effect measurements will also used wherever suitable.