High-quality ZnO films were grown on sapphire (001) substrates by the atomic layer epitaxy (ALE) technique using DEZn as a Zinc precusor and $H_2O $ as an oxidant at both $170^{circ}C$ and $400^{circ}C$ which are in the ALE and the CVD process temperature ranges, respectively. The films were annealed in an oxygen atmosphere in the temperature range from 600 to 100$0^{circ}C$ for an hour and then investigate photoluminescence (PL) properties using He-Cd laser. PL intensity tends to increases as the annealing temperature increase for both the annealed ZnO films grown at $170^{circ}C$ and $400^{circ}C$ , while PL did not nearly occur at the as-deposited ones. The PL intensity of the ZnO film grown at $400^{circ}C$ is low after it is annealed at high temperature owing to a large number of Zn-Zn bonds although it has increased in the visible light wavelength region after annealing. In contrast the PL intensity has increased significant in the visible light region after annealing