八-羟基喹啉铝薄膜光致发光的厚度依赖性质

In situ thickness dependent photoluminescence (PL) measurements of tris(8-hydroxyquinoline) aluminum(Alq3) film were performed. At the beginning of Alq3 deposition on the glass substrate, the Alq3 emission showed a sharp red-shift. Further deposition of Alq3 resulted slight red-shift, and finally tended to saturated value. The total red-shift of about 12 nm was observed for the Alq3 film thickness range from 2 to 500 nm.This red-shift was attributed to the change from the 2D to 3D exciton state with increasing Alq3 film thickness. Meanwhile, the PL intensity of Alq3 emission increased continuously, and showed a rate change at the initial deposition of Alq3 due to non-rediative decay of excitons arised from the interaction between excitons and the substrate, and finally tended to saturation with the Alq3 thickness.     

八-羟基喹啉铝薄膜光致发光的厚度依赖性质

通过原位测量对八-羟基喹啉铝薄膜(Alq_3)光致发光的厚度依赖性质进行了研究.在 Alq_3向玻璃衬底沉积的初始阶段,Alq_3光致发光谱峰发生了显著红移,此后谱峰随着 Alq_3厚度的增加红移变缓并趋于饱和.Alq_3薄膜厚度从2nm 逐渐变化到500nm 时,Alq_3谱峰位总红移约为12nm.这种 Alq_3薄膜沉积的初始阶段 Alq_3谱峰的显著红移可归因于二维激子向三维激子态的转变.同时,由于激子同衬底的相互作用所引起的非辐射衰变,在 Alq_3沉积的初始阶段 Alq_3光致发光谱峰的强度呈现不同的变化,随后该谱峰的强度随 Alq_3薄膜厚度的增加而快速增加,并在薄膜厚度较大时,趋向于饱和.