製成不同像素尺寸的紅色無稀土螢光材料薄膜之研究

Abstract

光主宰了人類的夜生活，照明設備的開發也大大提升了人類的活動範圍及生活品質，造就了科技與文明的進步。現今的人們人手一機、一筆電、一平板，回到家中又有超大尺寸的電視可欣賞節目，隨處可見的顯示器、顯示屏幕，而這些吸引我們目光的發光元件在它被製造的過程中，我們的環境卻要付出慘痛的代價，人類的身心健康也受到了影響，因為此高效率發光元件的材料含有稀土元素或重金屬元素，而本論文將會提出一種不使用稀土元素及重金屬元素之的材料製造出高效率的螢光薄膜，其能降低製造成本，也有望解決巨量轉移的良率問題及轉移速率問題。 本論文的最終結果是做出微米級的高效率紅色螢光陣列，實驗一開始是先從多種紅色有機螢光染料中選取一種適合的螢光客體染料，也就是DCJTB作為我們這次實驗的有機螢光染料。確定有機螢光染料後，我們開始嘗試使用多種不同的溶劑與DCJTB及PVP混合去製作出螢光溶液，使用積分球以藍光LED光源激發量測放光光譜並計算量子效率。使用溶液態最佳量子效率配方進行薄膜的製程，調整不同的旋塗參數製程出平整的薄膜並烤乾，並量測其量子效率及吸收率。目前以PVP為主體的製程結果所計算出最佳的薄膜的量子效率為85%。 使用PVP作為薄膜主體材料的過程中，我們發現此高分子材料是親水性的，對未來製程陣列的過程中會有困難，因此尋找了新的薄膜主體材料PVB替代，在尋找的新材料的同時，我們嘗試使用UV封裝技術測試PVP為主體的螢光薄膜在大氣的環境下能保存多久，並與沒有封裝的薄膜做比較。 研究的第二階段是以PVB作為薄膜主體材料進行薄膜製程，同樣先找出DCJTB與PVB混合的溶劑並量測放光光譜及計算量子效率，找到良好的旋塗參數製程平整的薄膜並開始製程陣列。而目前以PVB為主體的製程結果所計算出最佳的薄膜的量子效率為89%，吸收率為41%。陣列的製程中我們嘗試了曝光參數及氣體蝕刻參數，讓最終的陣列可得到一完整的長方體且與我們製程時所使用的光罩尺寸一致，尺寸大小有60μm*20μm及6μm*2μm兩種。 未來我們想要在同一片基板上呈現出RGB三種顏色，藍光LED為基底以光致發光激發綠色螢光陣列及紅光螢光陣列，藉由控制藍光LED的亮度混合出不同顏色，達成全彩的微米級像素製作。

Light has dominated human’s nightlife and the invention of lighting device has greatly increased the scope of human activities and the quality of life, resulting in improvement in technology and civilization. Nowadays, almost everyone owns a smart phone, a laptop, or a tablet, and we can watch programs with a big-sized television. Various types of monitors can be seen everywhere, but the production of luminous element has increased the burden on our environment. Moreover, the materials of highly efficient luminous element contain rare-earth or heavy metal elements, causing damage to human health. Therefore, the present thesis aims at adopting materials that contain no rare-earth or heavy metal elements and producing highly efficient fluorescent thin films. These films not only can reduce the cost of production of luminous element but also solve the problems of mass transfer yield and the transfer rate. Our goal is to produce highly efficient red microarray. In this first phase of our experiment, we chose one suitable fluorescent doping - DCJTB from multiple red organic fluorescent dyes to be our sample. Different solvents were mixed with DCJTB and PVP to produce fluorescent solution. By using integrating sphere, the blue LED was emitted to measure excitation spectrum and calculate quantum yield. In order to produce flat thin films, we adjusted spin coating parameter and measured its quantum efficiency rate and absorption rate. In the study, the best quantum efficiency of the thin film is 85% made by the PVP-based process. When using PVP as our host material to produce the thin film, we found that high molecular polymer material was hydrophilic, which might cause difficulties in future production of the array. Therefore, PVB material was adopted to replace PVP. We also tried to use the UV packaged technique to test PVP fluorescent thin film under 1 atm, and compared its outcome to unpackaged technique. During the second phase of our experiment, we used PVB as the host to produce thin film. Likewise, the suitable solvent was mixed with DCJTB and PVB and measured its excitation spectrum and calculated quantum yield. In the study, the spin coating parameter was also adjusted and to measure its quantum efficiency rate and absorption rate, so the best quantum efficiency of the thin film calculated by equation is 89% and the best absorption is 41% made by the PVB-based process. During the production of array, we tried to adjust photolithography parameter and RIE parameter in order to get a complete cuboid, which was consistent with the mask size that we used. The mask size of 60μm*20μm及6μm*2μm were used. In the future, we would like to demonstrate RGB colors on one piece of substrate. Blue LED will be the base to emit green and red fluorescent array. The luminance of the blue LED will be controlled to generate different colors so that we can produce full color micro pixel.