發光元件之發光層薄膜以往多以微影蝕刻為主，其缺點為製造時間較冗長約3~6個月，且無法控制薄膜之缺陷密度。隨著奈米科技的蓬勃發展，可利用奈米粒子聚集薄膜結構，透過微粒間作用力之調控將使得微粒聚集更加緊密。然而，目前發光效率不佳的問題尚未解決，主要原因為發光層薄膜中分子排列不規則而形成缺陷，造成載子在薄膜結構之傳輸效率變差，目前電光轉換之量子效率約為18%，可望改善量子效率為25%。因此，本研究將建構一套完整的微粒聚集理論與載子傳輸理論模型及其電腦模擬系統，以精確掌握其電光轉換之量子效率。

　　本文針對提升發光元件之電光轉換效率，首先定訂指標參數-量子效率。為提高量子效率必須降低發光層薄膜缺陷密度以改善載子之傳輸效率，本文利用分子動力以微觀角度探討微粒聚集行為，配合無因次邊界長度(NBL)分析微粒排列情況，並估算其缺陷密度，同時利用載子傳輸理論模型，估算電子與電洞在薄膜結構之復合效率。爾後，將本文之模擬結果與文獻資料作比對，確認本文理論模型之可行性，並根據本文所建構之設計流程應用在發光二極體與微探針發光元件上，以驗證本研究所建構理論模型之實用性。

　　由本文所建構之奈米微粒聚集理論模型，在模擬過程中將考量所有系統參數如溶液離子強度、接觸角、漢馬克常數、液面高度等，經過統計學方差分析研究發現，溶液離子強度與接觸角對系統微粒聚集行為影響較顯著；在本模擬系統中，調控離子強度與接觸角確實可降低薄膜缺陷密度約15%。而在載子傳輸模型中，我們將缺陷密度納入考量，模擬結果發現電流密度誤差值可由25.8%降至8.3%，較傳統理論值更貼切實驗值。此外，藉由本文所建構之理論模型與設計模擬流程進行發光元件之應用設計例。在發光二極體之模擬結果中可發現，在相同之量子效率下，由本文所建構之理論模型可精確的調控參數降低發光層薄膜缺陷密度，以得到較低之驅動電壓(9V降至5V)；而在微探針(microprobe)發光元件之模擬結果，可獲得較低之缺陷密度約 ，量子效率約改善20%與預期相差5%，其中誤差原因可能是多考慮的極板的歐姆阻抗原因。

　　The film of emitting layer on the electroluminescence devices was fabricated by etching in the past. It usually takes lots of time during the etching process and reduce the density of defect to a desired level. With the development of nanotechnology, it is now feasible to aggregation nanoparticles to design the film structure. The nanoparticles will aggregate more closely by controlling the their reactions, However, luminescence efficiency is mainly depends on the defect of the film on emitting layers resulting from irregular alignment among moleculars because the defect causes inefficient carrier transmission. For this reason, the goal of the work is to develop a theoretical model to accommodate the structure of nanoparticles aggregation and the details of carrier transmission. In order to precisely characterize the quantum efficiency of the electro-photo translation well through the theoretical model, a computerized simulation system based on molecular dynamics theory was established.

　　In order to meet the objective of raising the electro-photo translation efficiency, we define an index parameter for quantum efficiency of the luminiferous component. The behavior of nanoparticles aggregation process was we obtained via a molecular dynamics approach. In addition, the defect density is estimated by analyzing the particle allocation situation with non-dimensional boundary length. At the same time, by using the carriers transmission theory, a recombination efficiency of electron and the hole on the film structure was estimated. Eventually, the comprehensive model has been established. The computed results obtained by using the proposed simulation system are employed to compare with experimental data in literature. It is found that the results obtained by the present model agree well with those given in the literature. The design procedure presented in the work, was found practical and accurate for the application in light emitted devices and microprobes.

　　Several system parameters that are closed influence the film development including the of ion solution , contact angle, Hamaker number, height of interface, was carefully studied. It is found via statistics analysis that the intensity of ion solution and the contact angle are significantly important factors affecting the behavior of particle aggregation. The simulated result showed that the estimated current density is closer to experiment data than those obtained by the traditional theory computed. Two different design examples are presented to illustrate the efficiency of the presented procedure that can be used to characterize more accurately the physical parameters preferred luminiferous efficiency can be achieved.

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