本論文主要探討以化學氣相傳輸法成長層狀半導體二硫化錸晶體之奈米結構電傳輸特性。利用機械剝離法由二硫化錸單晶分離成二維奈米結構，並利用聚焦式離子束技術製作二維奈米結構之歐姆電極。該層狀半導體在同一層平面(ab-plane)具有非對稱性，結果發現沿平行b晶軸方向製作電極的奈米結構電導率大於垂直b軸方向製作電極的電導率至少三十倍，同時厚度為20到200nm的奈米結構電導率比塊材晶體高出至少兩個數量級。二硫化錸奈米結構載子活化能相較於塊材相對較低。因此推測二硫化錸可能擁有較高的表面傳導率或較高的表面載子濃度，實驗上排除了人為因素包含基板的載子注入、離子束轟擊造成表面損傷以及接觸電阻的影響。此外，藉由光電導量測，觀察到奈米尺度下二硫化錸的光電導傳輸仍受非等向特性影響，平行b軸歸一化光電導增益大於垂直b軸約五十倍。綜合暗電導與光電導量測結果，推測是由非等向性的遷移率所導致。

We report the electronic transport properties in layer semiconductor of rhenium disulphide (ReS2) grown by chemical vapor transport (CVT). The ReS2 layer nanostructure devices were fabricated using focused-ion beam (FIB) deposition and platinum (Pt) as the contact metal. It is found that the electrical conductivity along the b-axis is thirty times higher than that perpendicular to b-axis for nanostructures. The nanostructures prepared by mechanical exfoliation exhibit over two orders of magnitude higher conductivity than that of their bulk counterparts. These results imply the presence of higher surface conductivity or electron surface accumulation in this layer semiconductor system. The smaller activation energy of carrier were also observed for the ReS2 nanoflakes in comparison to the bulk crystals. The potential artificial effects, that could result in a high electron density at the surface, including electron injection from the substrate and surface damage by ion bombardment, were excluded. In addition, the anisotropic photoconductivity was also observer in the ReS2 nanoflakes. The normalized gain along b-axis is fifty times higher than that normal to b-axis. Both the dark conductivity and photoconductivity studies indicate a higher mobility for the electric transport along the b-axis compared to that normal to b-axis.

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