本論文主要探討以化學氣相傳導法所成長的六方晶系二硫化鉬層狀半導體與不同功函數金屬之歐姆接觸。我們利用機械剝離法移除暴露在大氣中之層狀晶體表面的電子聚集層，使我們可以探討具有新鮮表面的二硫化鉬(fresh MoS2)電性。研究發現在鉻、鎳、白金三種電極中，白金最為適合做為歐姆電極的材料，不論是在具有新鮮或是舊有表面的二硫化鉬(non-fresh MoS2)都能展現良好的歐姆接觸，其最佳的電導率大約為0.05~0.25 Ω-1cm-1。另外在本文中發現沉積薄膜前使用反向式濺鍍蝕刻(inverse sputter etching)做表面的處理，藉由降低接觸電阻，能有效的提升半導體的電導率，因此能將歐姆接觸較差的鉻電極之二硫化鉬電導率從0.002~0.004 Ω-1cm-1提高到0.061~0.131 Ω-1cm-1。

The quality of ohmic contacts on molybdenum disulfide (MoS2) layered semiconductors grown by chemical vapor transport using the metals with different work functions have been investigated. We studied the electrical properties in the MoS2 without surface electron accumulation fabricated by mechanical exfoliation. Among Cr (chromium), Ni (nickel) and Pt (platinum) metals, it is found that Pt is the optimal ohmic metal for the MoS2 single crystals with the fresh and non-fresh surface. The optimized conductivity of MoS2 using Pt electrodes is 0.25 Ω-1cm-1. In addition, the conductivity values of MoS2 using Cr electrodes have been improved from 0.002~0.004 Ω-1cm-1 to 0.061~0.131 Ω-1cm-1 by the pretreatment of inverse sputter etching technique.

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