隨著電子晶片的尺寸逐漸縮小，半導體前端晶圓製造方面面臨各式挑戰，後端電子封裝技術部分亦出現急需克服的屏障。例如電子封裝技術中銅與錫易於發生原子交互擴散行為，形成金屬間化合物及錫鬚晶，導致界面電阻率急劇升高進而使電子元件失效。本研究重點在於探討以銅鋁合金做為金屬玻璃阻障層與多晶銅間的擴散行為與機械性質。在理論模擬方法上，使用分子動力學模擬法與EAM勢能函數作為理論基礎，並配合開放式軟體LAMMPS作為工具，分析在不同系統溫度、冷卻速率及合金比例等條件下之銅鋁合金與多晶銅間的均方根位移、擴散系數及受單向拉伸時整體結構的應變分布、拉伸時空孔的破壞過程。
結果顯示擴散行為方面，金屬玻璃結構較晶態結構熱穩定性較佳，晶態結構於擴散模擬中在高溫時傾向出現急劇的擴散行為。擴散後剩餘非晶態結構比例越高之結構擁有最佳的擴散阻擋能力，因其不具有晶界等良好的擴散途徑；機械性質方面，金屬玻璃呈現較晶態結構差之機械強度，屬於較為延性的破壞行為。當上層晶態結構比例越高時，空孔破壞發生於銅鋁合金與多晶銅界面處，非晶態結構比例越高時，空孔破壞傾向發生於銅鋁金屬玻璃內部，此代表晶態結構機械強度較界面處及非晶態結構來的高。

With the gradual shrinkage of the size of electronic chip, there are a lot of challenges revealed in the semiconductor front-end process. In the same time, some problems should be apparently overcome in the back-end process, especially for electronic packaging. For example, copper atoms and tin atoms are susceptible to migrate and diffuse to each other, resulting in the formation of intermetallic compound (IMC) as well as tin whisker, which causes interface resistivity dramatically increasing and makes the components failed. In this thesis, the behavior of copper-aluminum (Cu-Al) alloys utilized as metallic glasses barrier was investigated. Moreover, not only the diffusion behavior but also the mechanical properties between the barrier and polycrystalline copper were evaluated and discussed. Molecular dynamics simulation was carried out by the program package LAMMPS with Embedded-Atom potential. We analyzed mean square displacement, diffusion coefficient, as well as the strain distribution of structure and the failure process during tensile test under the different condition, such as system temperature, cooling rate, molar ratio of alloys. The results show that, in terms of diffusion, the structure of metallic glasses has a great thermal stability compared with crystalline. Crystalline tends to reveal dramatic diffusion at the high temperature. It has the best barrier capability in the structure which possesses higher ratio of amorphous structure remained after diffusion because there is no boundaries as diffusion path. In respect of mechanical properties, metallic glasses perform weaker mechanical strength than crystalline, but better ductility. When the ratio of crystalline in barrier layer is high, pores shows up between the Cu-Al alloys and polycrystalline copper. In contrast, while the ratio of amorphous is high, pores would rather tend to appear in the interior of Cu-Al metallic glasses, which indicates that the mechanical strength of crystalline is stronger than that of the interface and that of amorphous.

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