P-Type ZnO Films

70665 The availability of p-type transparent conducting oxides (TCOs) with good properties would impact solar cell technology as well as a number of other fields. Although some new p-type TCOs have recently been demonstrated based on Cu and Ag oxides, a p-type ZnO thin film would be particularly valuable due to its high temperature stability, ease of deposition, and availability in single crystal form for substrates. This project will refine and optimize the production of p-type ZnO films by a metalorganic chemical vapor deposition (MOCVD) process. The approach will build on previous results, which demonstrated nascent p-type ZnO films and identified technical issues that must be overcome to achieve p-type ZnO routinely. Phase I will modify a reactor to remove sources of n-doping impurities, refine the p-doping process to demonstrate repeatable and reliable results, characterize p-type ZnO samples, and disseminate results. Commercial Applications and Other Benefits as described by the awardee: A p-type ZnO would enable a new class of transparent diode devices (including detectors, LEDs, and lasers) and transistors (potentially for displays), and would provide an alternative p-type TCO (potentially enhancing OLEDs, photovoltaics, and EL materials).