電激發光裝置介電層與發光性質之研究

The Luminescence Characteristics of Dielectric Layers in Electroluminescence Devices

彭春榮(Chun-Jung Peng)

指導教授 ： 唐自標

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00570

摘要

科技始終來自於人性，電激發光裝置是可撓性的面光源，具有輕薄耐衝擊等優良特性，使產品攜帶方便且易加工，可剪截成不同形狀，使終端產品有更寛廣的應用。為了響應節能減碳，本研究使用不耗能的手動網版印刷製程來製作層狀結構的電激發光裝置。其中黏結劑扮演著極為重要的角色，分別與螢光材料及介電材料混合成漿料後，進行網印塗佈來依序製作發光層、介電層及銀膠電極層。有鑑於商用黏結劑與介電漿料之價格昂貴，本研究著重於裝置中的介電層，開發具有巿場競爭力之黏結劑，使用不同粒徑之介電材料（鈦酸鋇及碳酸鋇），依粉膠配比1:2及2:3 wt%，製作一層、二層及三層介電層，在不同電壓下來探討裝置的發光性質；再與商用介電層漿料所製作的裝置來比較其發光性質。近年來由於石油價格攀升及人類意識到能源的珍貴，能源危機已經變成是全球性的議題了，降低產品的能耗及提升效率已成為刻不容緩且值得深思的重要課題。因此，本研究中也探討了裝置的起始電壓與發光性質的關係。最後，以粉膠配比1:2 wt%(鈦酸鋇混合VP 黏結劑)在價格上是具有巿場競爭力的；在發光性質上，也可與商用黏結劑來並駕其驅。在起始電壓方面，與商用環氧樹脂黏結劑（混合鈦酸鋇）之2.7 Vdc來比較，本研究開發的VP 黏結劑（混合鈦酸鋇）也有優異的表現，其粉膠比為1:2 wt%，僅需3.3 Vdc即可驅動裝置，達到1 Lux的發光強度。從研究結果來看，具有圓滑外形且粒徑小的鈦酸鋇，其發光強度較高；隨著電壓的增加，裝置的發光強度也會隨著上昇； 隨著介電層層數的增加，裝置的發光強度也會隨著下降；而起始電壓愈低者，裝置所需的驅動能源愈小，即愈省電。

關鍵字

電激發光 ； 硫化鋅 ； 鈦酸鋇 ； 螢光粉 ； 介電材料 ； 黏結劑

並列摘要

Technology originated from humanity, the electroluminescence devices belong to surface light sources with flexible feature; they are light, thin, and easy to carry with anti-impact characteristics. Consequently, the shape of the devices can be modified easily in order to satisfy the applications among various end products. To be in response to energy conservation and carbon emission reduction, the multi-layer electroluminescence devices were produced using manual screen-printing process, which is non-energy-consumption. The light emitting layer, dielectric layer, and electrode layer were printed step by step.

Binders play an important role in producing phosphor paste and dielectric paste as a medium; and they are combined individually with phosphor powders and dielectric powders. As a result of expensive binders and dielectric paste in the market, this research focuses on dielectric layers in the devices, developing competitiveness binders, using dielectric materials（BaTiO3 and BaCO3）with different crystal size and shape, and screen-printing 1 thru 3 dielectric layers to probe into the luminescence characteristics under various driving voltage, also comparing with the dielectric layers produced using commercial epoxy resin binder.

Recently, due to the fact that the pricing of fossil oils surge rapidly, and human is aware of rare resources. Therefore, the energy crisis becomes one of the significant topics in global community. Reducing energy consumption and increasing efficiency can be considered deeply to demand immediate attention. For this reason, the relationship between threshold voltage and luminous intensity was also discussed in this research. Finally, the dielectric layers mixed with BaTiO3 powders and VP binder at 1:2wt% is cost-effective comparing to commercial dielectric paste because of excellent luminescence characteristics. The threshold voltage for dielectric layers mixed with BaTiO3 powders and VP binder at 1:2wt% is 3.3 V dc, and mixed with commercial epoxy resin binder is 2.7 V dc. The VP binder demonstrates excellent performances with competitiveness comparing to commercial epoxy resin binder. This means that only 2.7 V dc for epoxy resin binder and 3.3 V dc for VP binder can achieve 1 Lux of luminous intensity.

Based on the results of this research, we can conclude that BaTiO3 dielectric powders with smooth sphere shape and small crystal size can have higher luminous intensity. The luminous intensity increases with increasing driving voltage and decreases with increasing the number of dielectric layers. In addition, the devices with lower threshold voltage indicate that they do require smaller energy to operate and are energy-saving.

並列關鍵字

Electroluminescence ； ZnS ； BaTiO3 ； Phosphor ； Dielectric Material ； Binder

參考文獻

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