A micro light-emitting diode (μLED) is a key device for the future of advanced information. Owing to expand its application widely, the concept of the emission-color conversion using layered semiconductors as a color converter is proposed. In addition, it is demonstrated that layered semiconductors were transferred directly onto μLED chips, and the emission-color conversion is realized. The layered GaS_1−xSe_x alloy, whose energy bandgap can be controlled by tuning the S and Se compositions, was selected as a color converter. The photoluminescence (PL) measurements using a blue LED as an excitation source revealed that GaS_0.65Se_0.35 and GaSe can show green and red luminescence with center energies of 2.34 and 1.94 eV, respectively. The emission color of gallium nitride (GaN)-based blue μLEDs covered with GaS_0.65Se_0.35 and GaSe thin films were clearly converted to green and red, respectively. Furthermore, the emission color could be controlled by changing the film thickness. Thus, these results suggest the possibility of emission-color conversion of blue μLED chips utilizing layered materials.

中文翻译：

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层状半导体材料的光致发光用于蓝色微发光二极管（µLED）的发射颜色转换

微型发光二极管（μLED）是未来高级信息的关键设备。由于其广泛的应用范围，提出了使用层状半导体作为颜色转换器的发射颜色转换的概念。另外，证明了将层状半导体直接转移到μLED芯片上，并且实现了发光颜色转换。选择能通过调节S和Se组成来控制其能带隙的GaS _{1- x} Se _x层状合金作为颜色转换器。使用蓝色LED作为激发源的光致发光（PL）测量表明，GaS _0.65 Se _0.35GaSe和GaSe可以分别显示绿色和红色发光，中心能量分别为2.34和1.94 eV。覆盖有GaS _0.65 Se _0.35和GaSe薄膜的氮化镓（GaN）基蓝色μLED的发射颜色分别清晰地转换为绿色和红色。此外，可以通过改变膜厚度来控制发光颜色。因此，这些结果表明利用分层材料的蓝色μLED芯片的发射颜色转换的可能性。