The Study Of Effects Of Substrate Temperature And Laser Energy On The ZnO Films' Properties Produced By PLD

With the fast development of society and technology, the needs of good-quality light-emitting materials are more imperative and the researches about these materials are going much deeper than before.Zinc Oxide (ZnO) is anⅡ—Ⅵcompound wide-band-gap semiconductor with a band gap of 3.37eV and a large exciton binding energy of 60 meV at room temperature. Wide-band semiconductors attract much more attention because of the needs of short-wavelength devices. Theoretically, it can realize stimulated UV emission at RT, which makes it a promising material for using in ultraviolet light-emitting and laser diodes. Meanwhile,it also has been widely used in surface acoustic wave devices,transparent electrodes,sensors and so on.There are many methods for growing ZnO films, such as sol-gel method, sputtering, molecular beam epitaxy (MBE), atom layer epitaxy (ALE), metal-organic chemical vapor deposition (MOCVD), Pulsed laser deposition (PLD) and so on.PLD is a newly developed films growth technique which can fabricate high-quality films compared with other techniques, because of its advantages of simple hardware,atomic-layer control obtained by adjusting the laser energy density and repetition rate. In this technique, high density laser ablates the ZnO ceramic target and produces ZnO plume depositing on heated substrate in high vacuum background.In this paper, ZnO films were prepared on Si (100) substrates at various substrate temperatures and laser energy, and then annealing was conducted.The films were examined by X-ray diffraction (XRD), Photoluminescence (PL), Raman and Ellipsometry. Through the researches of the structural and optical properties of ZnO films, we analysis and discuss the effects of deposition parameters on the grown ZnO films. The results suggested that high quality ZnO films with highly c-axis oriention can be prepared by PLD.