Design and construction of a low cost MOCVD reactor for depositing yttrium barium copper oxide superconducting films

An MOCVD reactor capable of depositing superconducting thin films has been designed and constructed. An aerosol feed system utilizing an ultrasonic nebulizer was used in this reactor. MgO and LaAlO;From the experiments, it has been demonstrated that the home-made aerosol MOCVD reactor could make YBCO superconducting films at low cost. The processes were stable and repeatable. Both the feed system and the chamber were vastly simpler and easier to operate than commercial models. It is also modular so that further modifications such as using different feed nozzles, photo assisted or plasma assisted reaction are possible.;The transport processes in the reactor were modeled by using the computational fluid dynamics software "FLUENT." Several different feed nozzles were modeled and compared. A special nozzle was designed to provide uniform distribution of the reactant in the substrate surface.;Superconducting YBCO films were deposited by the aerosol MOCVD reactor. The critical temperatures (Tc) of the films were measured by the four-probe method. The films were also characterized by using X-ray diffraction spectrum (XRD) and scanning electron microscope (SEM).