Silver photodoping into Al–ZnSe for application to white light emitters

Room-temperature Ag photodoping into crystalline Al-doped ZnSe grown by molecular-beam epitaxy (MBE) has been achieved. A promising approach to apply to a patterned white light emitter has also been proposed. An Al–ZnSe with Ag islands was illuminated with a HeCd laser at 300 K and annealed in the MBE chamber. Then, their photoluminescence characteristics were measured in real time. The self-activated (SA) emission, observed in as-grown Al–ZnSe, undergoes a considerable change in intensity and band energy position through Ag photodoping and subsequent annealing. The resultant emission bands centered at 2.145 eV and 2.250 eV are assigned as a donor-to-acceptor pair transition related with Ag impurities rather than SA centers. In addition, chromaticity can be controlled by an adjustment of photoirradiated Ag-doped area.