论文部分内容阅读
以量子点电致发光器件(QLED)中能级分布和载流子浓度的关系为理论基础,研究了QLED发光层能级变化与驱动电压的关系,建立了数学模型。以CdSe/ZnS核壳结构量子点为发光层,计算了器件正常发光时的阈值电压,分析了电流密度与量子点中电子准费米能级与空穴准费米能级之差的关系。结果表明,当驱动电压大于9.8V时,CdSe/ZnS中电子的准费米能级与空穴的准费米能级之差大于1.03eV,量子点电致发光器件正常发光;理论模型证实由于电子在发光层与电子传输层界面的大量积聚,导致淬灭发生,降低发光效率。
Based on the relationship between energy level distribution and carrier concentration in quantum dot electroluminescent device (QLED), the relationship between the level change of QLED light emitting layer and driving voltage was studied and a mathematical model was established. The CdSe / ZnS core-shell quantum dots were used as the light-emitting layer to calculate the threshold voltage of the device during normal light emission. The relationship between the current density and the quasi-Fermi level of electron and the quasi-Fermi level of holes was analyzed. The results show that when the driving voltage is higher than 9.8V, the difference between the quasi-Fermi level and the quasi-Fermi level in CdSe / ZnS is larger than 1.03eV, and the quantum dot electroluminescence device emits light normally. The theoretical model confirms that A large amount of electrons accumulate at the interface between the light-emitting layer and the electron-transporting layer, causing quenching to occur and lowering the luminous efficiency.