以液態封裝法提升量子點白光發光二極體性能之研究

Abstract

白光發光二極體具有高效率、體積小、良好可靠性與節能等優點，因此近年來越來越受到人們的重視，逐步取代傳統發光燈源。現今多以藍光發光二極體激發黃色螢光粉做為白光光源，但鮮豔度不佳;目前最具潛力的量子點螢光材料，具有極窄的半高寬，並有發光波長能隨粒子大小調變的優點，可以製作高色品質的白光發光二極體。 於第一部分的研究中，我們利用紫外光二極體激發寬帶寬的白光量子點，省去混合藍綠紅量子點時，調配比例所需的複雜手法，搭配液狀之量子點螢光粉封裝方法，將量子點封裝於高透光度石英盒中製作出具有高發光效率及高穩定度的白光量子點發光二極體。 於第二部分的研究中，我們使用無毒的石墨烯量子點及多孔矽量子點取代商用硫化锌包覆硒化镉量子點，利用紫外光二極體激發液態封裝量子點，製作出冷白光及暖白光兩種色溫之白光發光二極體，暖白光在演色性上有高達95、演色性(R9)也高達88的良好表現。

White light emitting diodes were the high luminous, small size, stable reliability, and energy saving devices, and which were more and more popular recently. Nowadays, most of white LEDs fabricated by yellow phosphor pumped by blue light-emitting diodes, which were with any problems such as poor CRI and color quality. Therefore, the most potential fluorescent material: quantum dots have received any attention due to the property of narrow emission linewidth, size dependent tunable bandgap, which can fabricate the high color quality white QD-LED. In the first section, we synthesis the broad band emission white QDs pumped by UV chip, to demonstrate an excellent luminous and color quality white LED by a liquid type package approach. The liquid type package fabricated by the high transmittance quartz cell with the liquid quantum dots inside to produce high efficiency and high stable white QD-LED. In the second section, the nontoxic graphene QDs and porous silicon QDs have been prepared to replace the heavy metal materials: CdSe/ZnS QDs for QD LEDs. This study demonstrates the nontoxic neutral white and warm white liquid type LED pumped by UV chip. The combination of the graphene QDs and the porous silicon QDs of warm white liquid type LED can achieve excellent values of CRI (95) and R9 (88).