Pulsed Laser Deposition Of Cu-doped Zno Thin Films

ZnO is a direct wide band-gap semiconductor material,and its band-gap is 3.37eV at room temperature.Besides promising thermal and chemical stability,excellent optical and electrical properties make it widely used in many fields.Such as ultraviolet light-emitting diodes, laser diodes and photodetectors.After a long time research for pure ZnO,it becomes significative to investigate ZnO film doped with rare material.In this paper,we explored pulse laser deposition(PLD) technology by KrF excimer laser to obtain Cu-doped ZnO thin films. Microstrueture and optical properties were studied systemically under different substrates temperature and annealing temperature.1.Cu-doped ZnO thin films were prepared by PLD technology in different substrate temperature under 5Pa oxygen pressure.Annealed treatment in 400℃has been explored.The results suggest that the Cu-doped ZnO films can obtain wurtzite structure with strong c-axis orientation.Although the FWHM becomes smaller with the rise of the substrates temperature, the intensity of the XRD diffraction peaks of(002) crystal direction enhance observably,these indicated that the quality of the films was improved.2.Films were prepared on silicon substrates at 5Pa oxygen pressures.different annealed substrate temperatures such as 200℃,250℃,300℃,350℃and400℃were taken for 2h.The results indicated that the Cu-doped ZnO film which was deposited at 100℃and annealed at 300℃has the minimal FWHM.So it's obviously that it is the perfect condition for Cu-ZnO thin films to improve the quality of crystalline mierostructure.3.High quality thin films were deposited on pure glass substrates under the same condition which was used on silicon before.The transmission spectrum of Cu-doped ZnO/Glass films were surveyed by the UV-visible spectrophotometer.The results revealed that the transmission coefficient of thin films varied with the rise of the growth temperature.It displays the aggrandizement firstly then decreased finally.But on the contrary,It shows the decrease at the first then increased at the last when thin films annealed at different temperature.So it gives us a new direction to optimize the grown condition to improve the quality of crystal.