Shi, YujunPahlevani, MajidRahmati, Mohammad2019-01-282019-01-282019-01-22Rahmati, M. (2019). Effect of quantum barrier on the performance of quantum dot light-emitting-diodes (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/109867This work presents a new structure with integrated poly(methyl methacrylate) (PMMA) quantum barriers (QBs) for use in quantum dot-light-emitting diodes (QD-LEDs). QD-LEDs can produce light with high colour purity in an efficient manner. Also, their durability compared to the organic LEDs (OLEDs) make them very attractive next-generation LEDs. In this thesis, the fabrication of a new QD-LED incorporating PMMA QBs is described in detail. The proposed structure utilizes colloidal CdSe/ZnS (core/shell) quantum dot nanoparticle emitters with a novel architecture where one emitting layer is replaced with a number of active layers separated by PMMA QBs. The wider bandgap of PMMA acts as an electron blocking layer and prevents electrons from passing the active region without producing photons. Thus, the proposed structure can tremendously reduce the electron leakage, particularly at high current densities. In this thesis it is also shown that the radiative recombination is highly affected by the number of QB layers in the recombination zone. The optimal number of QB layers is found, which is able to produce the maximum radiative recombination. The theoretical analysis, simulation results and experimental results demonstrate the feasibility of the proposed structure and verify its superior performance. It has been shown that the efficiency of QD-LEDs is increased from 6.8 cd/A to 17.8 cd/A with the maximum luminance of 194,038 cd/m2 by integrating the QBs into the active layer.enUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Quantum DotQuantum BarrierLight-emitting-diodesPMMAElectron LeakageEducation--Sciencesmaster thesis10.11575/PRISM/36124