Carrier Transport Behaviour of Molecular Doped Poly(N-Vinylcarbozole) in Polymer Light-Emitting Diodes

• 来源期刊: 中国物理快报（英文版）
• 学科: 物理学
• 年，卷（期）: 2002,（11）
• 页码范围: 1697-1699
• 页数: 3页
• 分类号: O4
• 语种: 英文

摘要

Single-layer polymer light-emitting diodes are prepared from blends of poly(N-vinylcarbozole) (PVK) doped with tris(8-hydroxy-quinoline) aluminium (Alqs) of 2wt% (sample a) and 0.2wt% (sample b). The onset of PVK transient electroluminescence (EL) is delayed with respect to that of Alq3 in sample a under pulsed excitation,while the EL onsets of Alq3 and PVK in sample b are simultaneous. The total carrier mobility of the Alq3-rich regions in sample a is larger than that of the PVK-rich regions. However, the total carrier mobility is homogeneous in sample b. The phase image of atomic force microscopy and photoluminescence spectra of samples a and b indicate that the separated phase of samples a and b exists in the PVK-rich and Alq3-rich regions. The variance of the doping concentration and separated phase in blends results in the different carrier transport mobility of Alq3-rich and PVK-rich regions.