隨著科技的發展，大眾對於電子產品的需求越來越多樣化，其中具備可撓特性之電子產品是近年來的發展趨勢，為了使傳統的電子元件擁有可撓的功能，大多利用可撓性基板取代傳統硬基板，而因為白雲母(Muscovite)具有二維晶格結構、可撓透明且能承受高溫與強酸鹼的環境，性質優於一般軟性基板，故白雲母非常適合作為可撓式之基板。
在本實驗中，由於氧化鋅(Zinc Oxide, ZnO)在光電元件的應用相當廣泛，並且能夠用於氮化鎵(Gallium Nitride, GaN)異質磊晶在其他基板上的緩衝層，具有高崩潰電壓、高激子結合能等優點，因此選用氧化鋅作為沉積於白雲母基板上之功能性氧化物薄膜。其中薄膜製程是利用濺鍍製程在雲母可撓性基板上長出氧化鋅晶種層，使其為單晶生長的方向以及成核位置，接著使用水熱法生長氧化鋅單晶薄膜。水熱法是種快速的磊晶方法，但同時也犧牲了表面的平坦度，若沒有良好的表面平坦度，會對後續薄膜磊晶之品質造成不好的影響，因此本實驗主要探討化學機械拋光應用於改善在可撓式白雲母基板上水熱生長的氧化鋅薄膜之表面平坦化，而化學機械拋光(Chemical Mechanical Polishing, CMP)主要是一種以化學反應結合機械研磨來達到晶圓全面平坦化的半導體製程。
由於以水熱法製備之氧化鋅薄膜具有可撓之特性(軟基板)，但是每片氧化鋅薄膜磊晶品質較難均一化，因此本研究先將商用氧化鋅基板(硬基板)進行化學機械拋光後，再參考其數據針對水熱氧化鋅進行化學機械拋光的實驗。
首先為了確認水熱氧化鋅適合在何種拋光墊下進行化學機械拋光，透過不織布型之長纖維結構拋光墊Suba800與發泡固化型之高分子結構拋光墊IC1010進行水熱氧化鋅的化學機械拋光實驗，結果顯示因IC1010對拋光液的涵養性能較Suba800低，因此可以使晶圓與拋光墊之間的拋光液較容易保持在拋光墊上，讓拋光時呈現潤滑的工作模式，對於水熱氧化鋅薄膜來說，此模式能夠讓表面較不會有剝離的現象，因此後續實驗將使用IC1010作為本實驗的拋光墊。
接著進行商用與水熱氧化鋅基板的化學機械拋光，從實驗結果發現在相同的下壓力下，不管是商用單晶還是水熱氧化鋅，都在轉速為20rpm時得到最佳的表面粗糙度，因為在轉速較低的情況下，拋光液在拋光墊上停留之容量與時間比較多，可以讓晶片與拋光墊之間保持在潤滑模式，因此水熱氧化鋅適合較低的轉速與下壓力進行化學機械拋光，最後從紫外-可見光譜儀量測光線之穿透率，從結果觀察到經過化學機械拋光後之表面在可見光波段(400-700nm)的穿透率皆有上升幅度。

With the advance of science and technology, the public demand for electronic products is becoming more variety, among which electronic products with flexible characteristics are the trend of development in recent years. In order to make traditional electronic components have flexible property, most of them use flexible substrate to replace traditional hard substrate, and because Muscovite has two-dimensional lattice structure, flexible, transparent, high temperature and chemical stability, and its properties are better than those of general
soft substrates, so Muscovite is very suitable for flexible substrate.
In this study, Zinc oxide(ZnO) was selected as a functional oxide film for deposition on Muscovite substrate because it is widely used in optoelectronic device and can be used as a buffer layer for gallium nitride heteroepitaxial on other substrates with high breakdown voltage and high exciton binding energy. The sputtering process is used to grow ZnO seeding layers on Muscovite substrate in the direction of single crystal growth and nucleation location, followed by hydrothermal growth of ZnO single crystal film. Therefore, this experiment is to study the chemical mechanical polishing to improve the surface planarization of hydrothermal grown ZnO film on flexible Muscovite substrate. The chemical mechanical polishing(CMP) is a semi-conductor process that combines chemical
reaction with mechanical polishing to achieve full wafer planarization.
Since the ZnO film was prepared by hydrothermal method, but it is difficult to uniform the epitaxial quality of each ZnO film. Therefore, before the hydrothermal ZnO conducts chemical mechanical polishing, the commercial ZnO substrate should be polished first and the data should be referred to. In order to confirm which polishing pad is suitable for the hydrothermal ZnO, a felted fiber structured polishing pad, Suba800, and a polymer structured polishing pad, IC1010, were used for the chemical mechanical polishing of hydrothermal ZnO. The results show that IC1010 has a lower slurry holding than Suba800, so it is easier to keep the slurry between the wafer and polishing pad, and it gives a
lubrication regime during polishing.
Then, chemical mechanical polishing of commercial and hydrothermal ZnO substrate was carried out. It was found that the best surface roughness was obtained at 20 rpm for both commercial single crystal and hydrothermal ZnO at the same down force, because at lower rotation, the slurry stays on the polishing pad for more volume and time, thus keeping the wafer and the pad in lubrication regime. Thus, hydrothermal ZnO is suitable for chemical mechanical polishing at lower rotation and down force. Finally, the transmittance of light was measured by UV-Vis spectrometer, and it was observed that the transmittance of the surface in the visible wavelength (400-700nm) increased after chemical mechanical
polishing.

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