二維材料在近二十年來發展迅速，由於其表面沒有懸鍵，因此在理論上
是能做出高電子遷移率的元件，加上維度的縮減更有利於進行垂直的堆疊，
因此有機會取代矽成為下個世代的主流材料。而金半接觸的工程一直扮演
著重要的角色，相比於傳統的矽半導體，二維材料難以進行重摻雜並且存
在費米能階釘扎的問題，使 Schottky Mott rule 所推估的蕭特基能障無法適
用，並導致元件效能受限。
本論文以化學氣相沉積法所成長的硒氧化鉍 (Bi2O2Se) 作為研究題材，
並利用氫氬混合電漿對金半接觸區域進行處理，我們預期能夠強化電極金
屬與材料之間的耦合，並提高電子注入效率，進而降低元件的接觸電阻。
金半接觸區經電漿處理後電晶體的最大電流達 285.53 µA/µm 與最大載子
遷移率 µ 達 380 cm2/V·s，且接觸電阻 Rc 為 4.9 kΩ·µm。然而在比較的過
程中發現了材料表面的晶向混亂，論文的第二部分則注重在材料品質的調
整。

Two-dimensional (2D) materials have developed rapidly in the past two
decades. Since there are no dangling bonds on the surface, they can the-
oretically make components with high electron mobility. In addition, the
reduction of dimensions is more conducive to vertical stacking, so it has
the opportunity to replace silicon becomes the mainstream material for the
next generation. The metal/semiconductor contact engineering has always
played an important role. Compared with traditional silicon semiconduc-
tors, 2D materials are difficult to be heavily doped and have the problem of
Fermi level pinning. Therefore, the Schottky barrier estimated by the Schot-
tky Mott rule cannot be applied, and the device performance is limited.
In the thesis, we first use chemical vapor deposition to grow Bi2O2Se
on the Mica, and use the Hydrogen-argon mixed plasma to treat the contact
area. We expect to strengthen the coupling between the electrode metal and
the 2D material, and improve the efficiency of electron injection, thereby
reducing the contact resistance of the device. After plasma treatment of the
contact area, the maximum current of the transistor reaches 285.53 µA/µm,
the mobility reaches 380 cm2/V·s, and the contact resistance is 4.9 kΩ·µm.
However, in the process of comparison, it was found that the crystal orien-
tation of the material surface is disordered, and the second part of the paper
focuses on the adjustment of material quality.

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