二維材料如同過渡金屬二硫屬化物 TMDC) 可用於製造電子器件，因為它們具有較大的直接帶隙和 非常小的 原 子薄層 0.7 nm 。然而， 透過光刻和離子植入等常規的製程技術容易使得 原子薄 層 損壞，產生具有明顯缺陷的原子薄層， 其中包括原子的破壞和不同原子間的鍵結 。因此，創造高性能和良好 電阻 的二維晶體管將是一個挑戰 。

在這項工作中，我們將結合兩種技術來降低接觸電阻，包括 六方氮化硼 hBN 與金屬所形成 的凡得瓦力金屬電極與氧氣等離子氧化技術形成單層氧化鎢(WOx)層作為非破壞性摻雜 (doping) 。此外，我們報告了氧化前後少層 WSe2 特徵的拉曼光譜和光致發光光譜。通過 輕微 的 氧氣 等離子 氧化 技術 (10 mW 15 s.c.c.m 60 sec) 使得只有 WSe2 的表層被氧化並轉化為 WOx 並且形成 p type doping 進而改善樣品品質 。此外，我們證明通過與蝕刻狀態的接觸可以拾取並與氧化的 WSe2 結合。

Two-dimensional materials such as transition metal dichalcogenides (TMDCs) could be used to create electronic devices due to their sizable direct bandgap and natural atomically thin layer (0.7nm). However, during the conventional fabrication process, such as direct metallization and ion implantation, the atomic thin material is easily damaged, producing a rough layer with apparent defect, including atomic disorder and interface bonding. Therefore, creating 2D transistor with high performance and good contact will be a challenge.
In this work, we will show a method that combines two techniques to reduce contact resistance, including van der Waal integration of metal with an etched hexagonal boron nitride (hBN), also known as via-contact technique, and using O2 plasma oxidation method to form a single tungsten oxide (WOx) layer as a non-destructive doping. Also, we report Raman and photoluminescence spectra of few-layer WSe2 characteristic before and after oxidation. By using gentle O2 plasma (10 mW, 15 s.c.c.m, 60 sec) only the surface layer of WSe2 is oxidized and convert into WOx, which can show hole-doping to improve the device performance. Moreover, we have demonstrated via contact with etched regime can be picked up and combined with oxidized WSe2.

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