| 摘要: | 光電感測器是將入射光能量轉換為電訊號的光電元件。其具有許多重要的應用，包括成像、光通訊、遠程控制、化學/生物傳感等。目前以GaN、Si 和 InGaAs 光電感測器為主要之商用產品材料。
近年來鈣鈦礦此新型材料對於光電元件的研究興起，因其具有優異的光吸收特性，並且具有較高載子遷移率、光吸收係數大的優勢，另外鈣鈦礦的可調能隙特性，有極大的潛力成為一種的新式的寬能隙之光感測元件。其中全無機鈣鈦礦無論其性能以及耐候性明顯優於有機-無機混合鈣鈦礦，因此使用全無機鈣鈦礦製備光電感測器。
本研究選擇全無機鈣鈦礦材料CsPbBr3，並以熱蒸鍍方式製備主動層，不僅薄膜緻密度高，且平整性高。再以高壓輔助熱退火的方式對主動層進行品質改善，更減少了其薄膜缺陷，且晶界更少。並且在元件中加入了TiO2作為電子傳輸層，更能使電荷提取效率增高。經研究發現，其開關比(on/off ratio) 達到了"1.42×" 〖"10" 〗^"4" ，且1.02 V的高開路電壓可以作為自供電光電感測器。並且在一般辦公室環境下(照度420 lux)的on/off ratio 仍有一定程度的響應效果。此有望成為低成本、高性能光電感測器元件，後續若將此元件配合電流放大等電路設計，相信能有利於日常生活中的光感測應用發展。
;Photodetectors are optoelectronic devices that convert incident light energy into electrical signals. It has many important applications, including imaging, optical communication, remote control, chemical/biological sensing, etc. At present, GaN, Si and InGaAs photodetectors are the main commercial product materials.
In recent years, the research of perovskite, a new material for optoelectronic devices, has been on the rise because of its excellent light absorption characteristics, high carrier mobility, and large light absorption coefficient. In addition, the adjustable energy gap characteristics has great potential to become a new type of wide-bandgap light sensing element. Among them, all-inorganic perovskite is obviously superior to organic-inorganic hybrid perovskite regardless of its performance and weather resistance, so all-inorganic perovskite is used to prepare photodetectors.
In this study, the all-inorganic perovskite material CsPbBr3 was selected, and the active layer was prepared by thermal evaporation, which not only has high film density, but also has high flatness. The quality of the active layer is improved by high-pressure assisted thermal annealing, which reduces the film defects and has fewer grain boundaries. In addition, TiO2 is added as an electron transport layer, which can further increase the charge extraction efficiency. After research, it is found that its on/off ratio reaches 1.42×104, and its high open circuit voltage of 1.02 V can be used as a self-powered photodetector. And in the general office environment (illuminance 420 lux), the on/off ratio still has a certain degree of response effect. This is expected to become a low-cost, high-performance photodetector device. If this component is combined with current amplification and other circuit designs in the future, it is believed to be beneficial to the development of light sensing applications in daily life. |
