It makes more attention to the ultraviolet (UV) optoelectronic devices. Up to now

the visible emission and ultraviolet lasing emission of ZnO has been the subject of much research. Although many groups put forward different mechanisms for visible luminescence from ZnO

a suitable mechanism is very difficult to establish. Of course

to carry out ultraviolet lasing emission is what one expects to do. In order to study these questions

high quality nanocrystalline ZnO and ZnO:Mn thin films were prepared by thermal oxidation of ZnS and ZnS:Mn thin films

which were deposited by using low pressure metalorganic chemical vapor deposition technique.In the discussion of visible luminescence mechanism

in order to prove that the oxygen vacancies or defects distribute on the surface of nanocrystallites

we presented the preparation of ZnO thin films doped with Mn and studied the photoluminescence of ZnO:Mn. Together with luminescence spectra

X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonant (EPR)

core-shell structure of nanocrystalline ZnO was put forward. In this thesis

we put forward that Vo

**

and [Vo

*

electron] or [Vo

**

two electrons]complex are luminescent centers of visible luminescence. Passivation on the surface of nanocrystalline ZnO was responsible for an energy potential high enough to prevent surface states trapping the electrons or holes photogenerated

it should block the pathway to form the luminescence centers as the Vo

**

and [Vo

*

electron] or [Vo

**

. A new visible luminescence mechanism was presented.