Improvement in photoluminescent characteristics of CuAlS_2:Mn red phosphor thin films prepared by multi source deposition method using Al_2S_3:Mn and Cu evaporation sources
Details
CuAlS_2:Mn red phosphor thin films have been prepared by multi-source deposition method by combining two electron-beam-guns evaporation using Cu metal and Al_2S_3:Mn source pellets and H_2S supply. It has been found that the compositional ratio of sulfur is very little even for the thin films prepared with enough much H_2S supply. The fact implies that sulfur is not efficiently incorporated into thin films during the deposition. To compensate the lack of sulfur, Al_2S_3:Mn pellets mixed with additional sulfur have been used as a evaporation source. The prepared thin films show a X-ray diffraction peak due to the CuAlS_2 (112) plane. The films also show a reddish-orange photoluminescence (PL) due to CuAlS_2:Mn, and a PL excitation spectra originating from the band-edge absorption of CuAlS_2.
