ZnO is a versatile semiconductor material with hexagonal wurtzite structure and has a band-gap of 3.3eV with a large exciton binding energy of 60meV at room-temperature. ZnO has attracted much more interest in the field of the information and display like GaN due to the application of UV emission. In the past

the structure and optical properties of ZnO film has been investigated extensively

in contrast

it is less known about the structure and optical properties of ZnO nanoparticles embedded in dielectric matrix. By utilizing the wave guide structure of ZnO/SiO

2

and the optical properties of quantum dots

ZnO nanoparticles embedded in SiO

2

can decrease the intensity of the photon scattering and self-absorption and increase the UV emission of ZnO nanoparticles. High quality ZnO nanoparticles embedded in SiO

2

was fabricated by zinc ion implantation (160keV

3×10

17

cm

-2

) into optical-grade silica substrate

followed by post-thermal annealing. The dependence of the component

orientation

average grain size and the quality of ZnO nanoparticles on the annealing ambient and time was studied by X-ray diffraction spectra. The zinc ion implantation with high dose and zinc atoms diffusion from silica surface can give rise to micro-hole

weak bond and breaken bond in silica near the implantation layer. During the annealing process

the disappearance of micro-hole and the reconstruction of weak and breaken bonds will occur. High quality ZnO nanoparticles embedded in SiO

2

was obtained as the annealing time increased to 2 hours at 700℃ in oxygen ambient. We can control the average grain size and density of ZnO nanoparticles by sequential post-thermal annealing zinc-implanted silica in nitrogen and oxygen ambient at 700℃. The average grain size of ZnO nanoparticles embedded in SiO

2

was in the range 18～26nm. The free exciton absorption and the UV emission of ZnO nanoparticles embedded in SiO

2

grown by post-thermal annealing zinc-implanted silica were observed by utilizing absorption spectra and micro photoluminescence spectra at room-temperature. The experimental results indicated that the stress affected the free exciton absorption peak of ZnO nanoparticles. The oxygen atoms that diffused to silica inside can decrease the defects that located in the boundary of nanocrystalline ZnO and were induced by the ion implantation during the annealing process in oxygen ambient. The dependence of the intense UV emission of ZnO nanoparticles on the temperature indicated that the impurity containment in the sample is less. The intense UV emission of ZnO nanoparticles can be attributed to the free exciton emission of ZnO nanoparticles at room-temperature. The relatively intense free exciton emission

the weak binding exciton and the free exciton replica emission of ZnO nanoparticles can be observed at 77K.