本論文的研究主要是藉由兩種新穎的鹽類作為電子注入層的材料，應用於高分子發光二極體(Polymer Light-Emitting Diodes, PLEDs)，此兩種材料皆可以有效降低高功函數金屬的功函數，減少電子注入所需的能障，使得元件效率與穩定性有大幅度的提升。而本篇論文分別對兩種鹽類探討其材料與元件特性。第一部分是使用硼氫化鈉作為電子注入層的特性探討；第二部份是使用四級胺鹽作為電子注入層的特性探討。
　　第一部分中，我們使用硼氫化鈉作為電子注入材料應用於高分子發光二極體，由元件特性圖中發現硼氫化鈉的確增進以高功函數金屬為陰極電極元件的效率，並藉由光伏量測法與紫外光電子圖譜的結果得知上述結果來自於陰極功函數的降低。此原因可能來自於硼氫化鈉和發光層與金屬電極的反應而來。
　　第二部分中，我們使用四級胺鹽作為電子注入層，一樣有效的提升元件的效率，並由光伏量測法和紫外光電子圖譜結果發現四級胺鹽有降低陰極的功函數的能力。此外，我們藉由小角度X光繞射儀發現四級胺鹽分子在發光層表面出現規則性的排列，並且排列方向垂直於主動層。因此我們從XRD數據和四級胺鹽之分子結構推測，四級胺鹽會產生方向朝向主動層之介面偶極，此偶極就是陰極功函數降低的來源。

In this study, we use two kind of novel salts, sodium borohydride (NaBH4) and quaternary ammonium salts, as electron injection materials into polymer light-emitting diode(PLEDs). Both can efficiently reduce the electron injection barrier between the high work function metal cathode and active layer to improve the stability and the performance of PLEDs. We will introduce the characteristics of NaBH4 and quaternary ammonium salts as electron injection layers (EILs) in PLEDs at first and second section, respectively.
In the first section, the NaBH4 was used as EIL in PLED. The device performance shows that the device with NaBH4 / stable metal (such as Al, Ag, Au) PLED is significantly superior to the PLED with plain stable metal. From Voc and UPS results, the improvement results from the decrease in work function of cathode part. We speculate that the change in work function is due to the specific reaction between active layer and NaBH4.
In the second section, we use quaternary ammonium salts as EIL in PLED. Quaternary ammonium salts can also reduce the work function of cathode by the observations of photovoltaic and ultraviolet photoemission spectroscopy measurements. X-ray diffraction measurement shows that quaternary ammonium salts have orthogonal crystal on the PF substrate. From XRD results and the molecular structure of quaternary ammonium salts, we think an interfacial dipole from cathode to PF would build up. This dipole can reduce the barrier between PF and high work function metals.

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