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Barium thioaluminate with europium (BaAl2S4:Eu) is the most efficient blue light-emitting material in inorganic thin-film electroluminescent devices. In order to fabricate full-color electroluminescent devices, blue light-emitting layers were prepared in several ways. Single target sputtering deposition is one of the effective methods for preparing blue luminescent layers. In this paper, a new structural target material is introduced and its preparation process is studied. The photoluminescence spectra of the prepared target showed that the two kinds of luminescent layers doped with europium at 3mol% and 5mol% had blue emission characteristics. The emission peaks of the UV-excited photoluminescence spectra at 290nm, 300nm and 320nm were all near 470nm. Therefore, the prepared target can be used for single target sputtering deposition of BaAl2S4:Eu thin films. XRD results showed that there were four different phases in Target 1: Barium tetraaluminium sulfide (BaAl4S7), barium sulfide (BaS) , europium sulfide (EuS) and barium aluminum oxide (BaAl2O4). In addition to these four phases, two other phases were detected in Target 2: Aluminum Sulphide (Al2S3) and barium thioaluminate (BaAl2S4). The results showed that Target 1 was more suitable for sputtering BaAl2S4:Eu thin films due to the hydrolysis of Al2S3. XPS and X-ray fluorescence spectra reflected the exact molar ratios of each element. In Target 1, the relative atomic concentration of Ba, Al, S and O was about 9:33:41:17. The molar ratio of barium to europium was about 1:0.03. In conclusion, Target 1 was more suitable for preparing blue light-emitting layers in inorganic electroluminescent devices.
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