這論文主要研究一種化學式為[Fe(TPPB)Cl2]．3DMF·5H2O（簡稱FeTCD）的鐵基金屬有機框架(MetalOrganic Framework，簡稱 MOF)材料單晶的電荷傳輸特性。FeTCD的微米晶體具有單斜晶系結構。為了製作元件，使用靜電膠帶機械剝離法將FeTCD單晶粉末分離成微米大小的晶體，然後使用雙束型聚焦離子束(Dual-Beam Focused Ion Beam)技術在微米晶體上沉積白金(Pt)電極，製備良好的微米晶體的歐姆接觸。暗電導量測顯示FeTCD微米晶體的電導率最高可達39 S/cm。根據變溫暗電導的量測，觀察到FeTCD晶體表現出半導體性的電荷傳導行為，而且具有非常低的活化能，最低僅為2.6 meV，表示當電荷進行跳躍傳輸時幾乎不需要額外的熱能輔助，證明FeTCD微米晶體具有極佳的電荷傳輸通道和有序的晶格結構，為電荷提供了一個相對無阻礙的環境進行傳輸。熱探針量測顯示此MOF晶體為p型半導體，其結果也與理論計算之結果相符。
另一部分，從光電導(photoconductivity)量測結果發現此MOF微米晶體具有明顯的光電流反應，隨著雷射強度增加，光電流呈線性的上升趨勢。於不同波長從可見光至紅外光的雷射照射下，FeTCD都表現出不錯的響應度(responsivity)，其中以紫光（波長 405 nm）具有最佳的光反應，其反應率可達 155 A/W。藉由時間解析光電導量測發現FeTCD晶體良好的光電導效率乃是源自於長載子活期 (carrier lifetime)，其活期可長達5秒。透過環境變化光電流量測，可進一步證明此MOF晶體遵循表面主導的光電導機制。

This thesis investigates the electronic transport properties in the microcrystals of [Fe(TPPB)Cl2]．3DMF·5H2O (referred as FeTCD) metal-organic framework (MOF) microcrystals with monoclinic structure. The fabrication of ohmic contacts for the microcrystals was achieved using the dual-beam focused-ion beam method. The I-V measurements demonstrated that the FeTCD crystals exhibit high conductivity reaching 39 S/cm. The exceptional conductivity can be attributed to the presence of multiple charge transport channels within the highly conductive FeTCD crystals. The characterization through hot probe measurements revealed the p-type semiconducting behavior in the crystals. The temperature-dependent conductivity measurements indicated extremely low activation energies for charge transport at the range of 2.63.3meV. The high conductivity and low activation energy suggest the presence of charge transport channels and highly ordered lattice structure in these MOF microcrystals.
Furthermore, the MOF crystals exhibit substantial photocurrent response. The photocurrent increases linearly with increase of light intensity. Photocurrent responses were measured at a broad wavelength range spanning from ultraviolet, visible to infrared (3751550 nm). The crystals exhibit the highest photoresponse at 405 nm (violet light). The optimal photoconductive gain reaching 475 was obtained. The ultralong carrier lifetime at the time scale of seconds was observed, which is probably the major cause of the efficient photocurrent generation. Additionally, the ambience-dependent photoresponse indicate that the photoconduction mechanism in this FeTCD crystals is primarily governed by the surface rather than the inner bulk.

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