鹵化鉛鈣鈦礦因其特殊的材料特性，已被應用於不同功能的元件上，例如:光電感測器、太陽能電池、發光二極體、電阻式記憶體等元件。目前眾多研究指出摻雜不同鹼金屬族與調整其摻雜濃度可以提升鈣鈦礦太陽能電池性能，然而在光電探測器上則較無探討鹼金屬族離子摻雜濃度改變對光電探測器之影響。
本論文分為兩大部分。第一部分討論在FA0.75MA0.25PbI3鈣鈦礦中摻雜不同濃度銫離子(Cs+)、銣離子(Rb+)以及共同摻雜兩者，研究其對鈣鈦礦薄膜的變化。由於銫的離子半徑比銣大，較符合公差因子以至於形成穩定的立方鈣鈦礦相，並提升薄膜的結晶性，形成高品質的薄膜，降低薄膜缺陷，提升鈣鈦礦的光吸收能力，Rb+由於其離子半徑較小，不能完全進入於鈣鈦礦中，雖會使薄膜晶粒大小提升以及抑制黃相鈣鈦礦，但會產生相分離以及團簇現象，造成鈣鈦礦光吸收能力下降。兩者共同摻雜雖會使晶粒大小提升且並無觀察到明顯相分離、團簇現象，但Rb+會連帶著Cs+於界面處偏析使得光吸收能力下降。
第二部分則是將第一部分的薄膜製作成太陽能電池與光電探測器元件，探討摻雜濃度對元件特性的變化。由於Cs+的摻雜可以提升結晶性，形成均勻、緻密且無孔洞的高品質鈣鈦礦薄膜，降低薄膜的缺陷，使太陽能電池與光電探測器性能明顯提升，當摻雜5% Cs+時擁有最佳特性。Rb+摻雜由於其相分離與團簇現象，造成光吸收下降，但仍在微量2.5% 摻雜下觀察到元件部份性能提升，乃是Rb+摻雜造成鈣鈦礦薄膜陷阱下降的影響，使太陽能電池填充因子上升與光電探測器之響應時間加快以及暗電流下降。 在有最佳性能之摻雜5% Cs+元件進一步摻雜Rb+，因Rb與Cs的偏析造成光吸收能力下降，使太陽能電池與光電測探器部分特性變差，但Rb+對於鈣鈦礦薄膜陷阱的改善使得太陽能電池填充因子與光電探測器之響應時間以及暗電流有進一步的改善，透過空間電荷限制電流法計算Cs+以及Rb+對鈣鈦礦薄膜陷阱密度的影響。元件響應時間由400微秒提升至100微秒，探測率由摻雜5% Cs+ 之1.15×1012 Jones提升至共同摻雜5% Cs+與5% Rb+元件之1.88×1012 Jones。

This research consists of two parts. The first part discusses influence of doping FA0.75MA0.25PbI3 perovskite with different concentrations of cesium ion (Cs+), rubidium ion (Rb+) and co-dopants(Cs+ and Rb+) on the properties of perovskite thin films. Because the ion radius of cesium is larger than that of rubidium, it is more in line with the tolerance factor to form a stable cubic perovskite phase, forms a high-quality perovskite thin film. Due to the smaller ion radius of rubidium, although the increases grain size of the perovskite thin film increase and suppressesδ-FAPbI3, phase separation and clustering will occur. Co-doping Cs+ and Rb+ ion will increase the grain size but rubidium will segregate at the interface together with cesium.
In the second part of this research, the effects of doping concentration on the device characteristics are discussed. Because doping Cs+ forms a high-quality perovskite thin film, significantly improving the performance of photodetectors. Rb+ doping causes phase separation and clustering of perovskite films, however, performance improvement of the devices is observed by doping 2.5% Rb+. The improvement is ascribed to the Rb+ doping that causes the reduction of trap density of perovskite, reducing the response time and the dark current of the photodetector. Further doping Rb+ into the device of doping 5% Cs+ causes the segregation of rubidium and cesium, therefore the performance of photodetectors declined. However, Rb+ doping reduces trap density that improves response time and dark current of photodetectors further. The trap densities of doping Cs+ and Rb+ in perovskite thin film are calculated by the space charge limited current method. As a results, the response time of the photodetector is improved from 400 s to 100 s, and the detectivity is increased from 1.15×1012 Jones with 5% Cs+ doping to 1.88×1012 Jones with 5% Cs+ and 5% Rb+ doping.

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