在本碩士論文之中，我們提出以PbS量子點材料作為吸光層製作量子點敏化光檢測器，藉由使用染料敏化太陽能電池結構，利用多孔性二氧化鈦光電極，用連續式離子層吸附與反應(the successive ionic layer adsorption and reaction, SILAR)製程方法吸附PbS量子點材料，並藉由TiCl4處理，修飾二氧化鈦光電極之介面，以增加元件之光響應表現。並發現當經過TiCl4處理後，元件之電性以及光響應特性有大幅的變化，不論在光響應速度或是光響應強度上皆有提升。推測此變化最主要來自於缺陷態以及二氧化鈦能階結構之改變。最後發現，TiCl4處理時間會對缺陷態之深度和數量分布造成差異，並從缺陷態對元件造成的影響提出機制並驗證。

The purpose of this thesis is to fabricate a PbS quantum dot sensitized photodetector. We use mesoporous TiO2 to adsorb PbS quantum dot and take the advantage of DSSCs to improve the performance of device. SILAR process, which provides a better response speed for device, is also used to replace the common colloidal quantum dot process. Furthermore, we find that the response speed, range, and intensity of device can be improved by using TiCl4 treatment of TiO2, which is due to the conduction band shift and the trap state of TiO2. We can further use different TiCl4 treatment times to control the trap state’s number and depth of TiO2. Finally, we propose and verify the mechanism for the influence of the trap state on the device.

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