在本論文中，我們探討了利用自我組織分子(self-assembled molecule)對透明導電薄膜進行修飾改善有機高分子光感測器元件的特性，並比較各個自我組織分子處理之間元件特性。自我組織分子附著於電極表面後，會因為分子本身的電偶極矩，使得透明導電薄膜的功函數得以調變。藉由選擇不同官能基，改變分子電偶極矩方向與大小。在本實驗所使用的自我組織分子當中，我們得到以1H,1H,2H,2H-Perfluorooctanephosphonic acid (FOPA)處理氧化銦錫(ITO)是有效的。在處理時間上，相較於常見的長時間處理(24hr)，我們發現在一分鐘的處理就有與長時間一樣的效果。其元件特性之外部量子效率(0V)為50%、暗電流比未處理的降低60%、感測度為未處理的1.7倍。在常用於電洞傳輸層PEDOT:PSS處理上，由於受到酸腐蝕的影響，暗電流為未處理的122倍，因此並不適合用於光感測元件上。我們同時也用氧化鋅鎵(GZO)進行元件的製作，發現在GZO的處理上2,3,4,5,6-Pentafluorobenzylphosphonic acid (FBPA)是有效的，其元件特性之外部量子效率(0V)為47%、暗電流比未處理降低62%、感測度為未處理的1.78倍。在經由PEDOT:PSS處理的GZO元件上，短路電流沒有如在ITO上有效的提升，主要是因為酸腐蝕的影響造成片電阻的上升使得元件特性下降。在本論文中，藉由SAM取代PEDOT:PSS，可以同時提升光電流以及減少暗電流，進而改善光感測器的元件特性。

In this thesis, we have investigated the characteristics of polymer photodetector fabricated on transparent electrode which is treated by self-assembled molecule (SAM) treatment and we also compared the characteristics of each the devices. After the SAM attach on the surface of the transparent electrode, the work function of transparent electrode can be modulated due to the molecular dipole moment. By choosing different functional group of the SAM, the direction and magnitude of the dipole moment can be changed. We obtained the result that 1H,1H,2H,2H-Perfluorooctanephosphonic acid (FOPA) is useful for indium-tin oxide (ITO) from all of the SAMs used in this experiment. In processing time investigation, we obtained the same result between short time treatment and long time treatment (24hr) which is often seen in journal. The device with FOPA short time treatment modified on ITO has incident photon to current conversion efficiency (IPCE) 50% and the dark current was 60% reduced compared to non-treatment device. Furthermore, the detectivity was enhanced by 1.7 times. In the treatment of Poly (3,4-ethylendioxythiophene) dope with poly (4-styrenesulfonate) (PEDOT:PSS) which is often used as hole transport layer, the dark current was increased by 122 times due to the erosion of the ITO. Thus, the PEDOT:PSS was not suitable for organic photodetector fabrication. We also used the gallium-doped zinc oxide (GZO) substrate for device fabrication and found that the 2,3,4,5,6-Pentafluorobenzylphosphonic acid (FBPA) is useful for GZO. The device with modified on GZO has IPCE 47% and dark current was 62% reduced compared to non-treatment device. Furthermore, the detectivity was enhanced by 1.78 times. In the PEDOT:PSS based GZO devices, the short circuit current was not increased as in ITO. This might mainly due to the increase of the sheet resistance which was caused by hard erosion of the GZO. In this thesis, instead of PEDOT:PSS by using SAM, the photocurrent could be increased and the dark current could be decreased at the same time which results in the improved photodetector detectivity.

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