二維(2D)異質雙面(Janus)過渡金屬二硫屬化物(TMDC)作為一類新興的二維
材料非常有吸引力，但只有幾種方法可用於製造它們，然而這些方法有過多的參
數需要調整且容易受到環境的影響。為了克服這些缺點，本實驗透過調整化學氣
相沉積的參數包含溫度、氣體流量及壓力，在藍寶石玻璃基板上成功生長出均勻
的單層二硫化鉬多晶薄膜，晶粒尺寸達到 40 – 50 μm。為了降低製作成本和時間，
我們利用電漿處理來改質生長出的二硫化鉬薄膜，將其轉變成 SeMoS。通過調整
功率和時間，我們製作出大面積的 JTMD SeMoS 薄膜。實驗中，我們將電漿功
率設置為 50 瓦，處理時間為 10 分鐘，從而製作出相對完整的 JTMD SeMoS 薄
膜。透過拉曼光譜、拉曼 Mapping、光致發光光譜及原子力顯微鏡分析樣品，結
果證實我們成功製作出大面積的 JTMD SeMoS。該材料的能隙為 1.7 電子伏特，
厚度為 0.8 nm，相當於單層 JTMD SeMoS 的厚度。

Two-dimensional (2D) Janus transition metal dichalcogenides (TMDCs) are a
highly attractive class of emerging 2D materials, but there are only a few methods
available for their fabrication. However, these methods often require adjusting
numerous parameters and are easily influenced by environmental factors. To overcome
these drawbacks, in this experiment, we successfully grew uniform monolayer MoS₂
polycrystalline thin films with grain sizes reaching 40 – 50 μm on sapphire substrates
by adjusting the parameters of chemical vapor deposition including temperature, gas
flow, and pressure. To reduce production costs and time, we modified the grown MoS₂
thin films using plasma treatment, transforming them into SeMoS. By adjusting the
power and duration, we produced large-area JTMD SeMoS thin films. In the experiment,
we set the plasma power to 50 watts and the treatment time to 10 minutes, resulting in
relatively intact JTMD SeMoS thin films. Through Raman spectroscopy, Raman
mapping, photoluminescence spectroscopy, and atomic force microscopy analysis of
the samples, the results confirmed that we successfully fabricated large-area JTMD
SeMoS. The material exhibits a direct bandgap of 1.7 eV and a thickness of 0.8 nm,
corresponding to the thickness of a monolayer JTMD SeMoS.

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