本論文主要探討 [Ni2(HFDP)1(BPYM)1(4H2O)]·H2O （以下論文簡稱為 NiHB ）疏水性金屬有機框架化合物 (metal-organic framework, MOF) 微米晶體之電傳輸特性。研究中所使用的 NiHB MOF 微米晶體具有三方晶系 (Trigonal crystal system) 結構。透過接觸角量測得出其角度為 125° ，顯示極佳的疏水性。元件製作上是利用機械剝離法將 NiHB 單晶分離成微米晶體，並利用聚焦式離子束 (focused-ion beam) 技術製作微米晶體之歐姆電極。暗電導量測顯示其電導率最高可達 208 S/cm 。熱探針量測結果顯示此 MOF 晶體為 p 型半導體。變溫暗電導量測顯示此 MOF 晶體具備半導體性的電傳導行為，並擁有極低的活化能，最低僅有 0.02 meV ，顯示電荷經由跳躍傳輸 (hopping transport) 時幾乎不需要熱能的輔助。此結果顯示 NiHB 微米晶體具備極佳的結晶品質與有序的晶格，可提供電荷在一個比較沒有阻礙的環境進行跳躍傳輸。
另外，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，光電流也呈現非線性的上升趨勢。於不同波長的雷射照射下，發現 NiHB 微米晶體對紫光具有最佳的光電流反應。不同波長的條件下， NiHB 微米晶體也都表現出不錯的反應率 (responsivity) 與光電導增益 (gain) 。藉由時間解析光電導量測發現此 MOF 晶體良好的光電導效率乃是源自於長載子活期 (carrier lifetime) 。透過環境變化光電導量測，可進一步證明此 MOF 晶體遵循表面主導之光電導機制。

The electrical properties of the [Ni2(HFDP)1(BPYM)1(4H2O)]·H2O (NiHB) metal-organic framework (MOF) microcrystals with trigonal structure and hydrophobic character were investigated. The ohmic contacts of the microcrystals were fabricated by using focused-ion beam method. The I-V measurements show the NiHB crystals with high conductivity up to 208 S/cm. Presence of several charge transport channels is attributed to the highly conductive nature of the NiHB crystals. Hot probe measurement shows p-type semiconducting characteristic. Temperature-dependent conductivity measurements reveal the extremely low activation energies for charge transport at the range of 0.025.3 meV. The high conductivity and low activation energy suggest highly ordered lattice structure in this MOF microcrystals.
Additionally, the NiHB MOF crystals also exhibit substantial photocurrent response. The photocurrent increases nonlinearly with the increase of light intensity. The MOF crystals show optimal photoresponse to the wavelength at 405 nm (violet light) compared to other wavelengths. The optimal photoconductive gain is 2200 and the carrier lifetime is as long as several seconds. The ambience-dependent photoconductivity measurement implies the surface-dominant photoconduction mechanism in the NiHB crystals.

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