| Zinc oxide is a well-known wide band gap (Eg = 3.18 eV) semiconducting material that exhibits an efficient blue-green emission at 520nm. ZnO has attracted considerable attention due its to various potential applications in optoelectronics, such as ultraviolet (UV) light emitting devices.; In this project, samples of pure ZnO, Bi3+ doped ZnO and alloyed semiconductors Zn1−xMgxO were prepared through solid-state chemical reaction, and optical spectral properties were investigated. It was found that the strong broad band emission was shifted to the blue side with increase of temperature.; The absorption edge shown in the excitation spectra of Zn1−x MgxO was found continuously to shift to the shorter wavelength, indicating an increase of the band gap in the alloys with content (x) of magnesium. Due to the possible decrease of the concentration of oxygen vacancies, the intensity of the band emission drops down with x.; In the Bi3+ doped samples, a red emission band from Bi 3+, centered at 650nm was observed. (Abstract shortened by UMI.)... |
