銅單晶因為其具有的表面特性而引起強烈的興趣與研究動機，它可用於一些材料的成長，如石墨烯及六方氮化硼。然而，製作銅單晶的過程通常很複雜且成本高昂。最近一些研究指出，透過熱處理的方式將多晶銅箔轉化為大面積的單晶銅箔是可行的。這個方式能夠簡化將多晶銅箔轉化為單晶銅箔的過程，並且降低成本。
在本研究中，透過在Ar/H2混和氣體中的熱處理，我們成功地將市面上購買的多晶銅箔轉化為單晶銅箔。我們實際測試了不同的實驗參數，其中包含銅箔的厚度(30 μm，50 μm及80 μm)、加熱時間以及加熱溫度。在生長條件優化之後，我們得到有著Cu(111)表面的單晶箔片。我們利用低能量電子繞射儀(LEED)、歐傑電子能譜術(AES)以及掃描穿隧顯微鏡(STM)來檢測這些箔片的表面結構。我們的結果顯示，單晶銅箔可作為表面研究中高度有序薄膜的基底，並且可以代替昂貴的銅單晶。

Single crystal copper has attracted great interests because of its valuable surface properties that can be used to grow some materials, such as graphene and hexagonal boron nitride. However, the methods for the fabricating copper single crystals are usually complex and costly. A few recent studies have demonstrated that it is feasible to transform thin polycrystalline copper foils into large-area single crystalline foils with heat treatment methods, offering a simple and less expensive way to obtain single crystals from polycrystalline copper foils.
In this study, we obtain single-crystalline copper foils from commercial polycrystalline copper foils by heat treatment under the mixture of gas Ar/H2. Different parameters of heat treatment are tested such as thickness of Cu foils (30 μm, 50 μm, and 80 μm), duration, and temperature. After the optimization of growth condition, Cu(111) single crystal is obtained. The surface structure is characterized by Low Energy Electron Diffraction (LEED), Auger Electron Spectroscopy (AES), and Scanning Tunnelling Microscopy (STM). Our results demonstrate that the single-crystal Cu foils can be used as substrate for highly ordered thin film for surface studies, and can be an inexpensive alternative to the Cu single crystals.

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