超奈米晶鑽石(ultrananocrystalline diamond films, UNCD)薄膜因兼具良好的物理化學性質及平坦的表面，在各方面應用皆優於傳統的微米晶鑽石薄膜。本研究先以電泳法沉積奈米鑽石顆粒於矽基板上，再經由微波電漿輔助化學氣相沉積系統(microwave plasma-enhanced chemical vapor deposition, MPECVD)成長UNCD。藉由掃描式電子顯微鏡(scanning electron microscopy, SEM)影像圖觀察鑽石顆粒沉積在矽基板上的分布情形與鑽石膜的表面形貌，以X光繞射分析其結構，並以電子場發射特性與拉曼光譜儀分析薄膜性質，由以上量測得知利用電泳法孕核所成長的UNCD與超音波震盪法孕核所得的UNCD具有相同的品質。此外，本實驗利用電泳法孕核沉積UNCD於矽奈米線陣列與碳化鎢基板，在矽奈米線陣列方面，不破壞矽奈米線的表面形貌，可有效達到孕核效果，於矽奈米線的尖端附著非常緊密且連續的鑽石顆粒，利於電子場發射特性。在碳化鎢基板方面，無論是電泳法孕核或超音波震盪法皆可成功的成長出UNCD。

In this work, we report the utilization of nano-diamond layer electrophoresis-deposited on Si to perform as a nucleation layer for growing ultra-nanocrystalline diamond (UNCD) film using microwave plasma-enhanced chemical vapor deposition (MPECVD) system. The morphology of the as-deposited diamond nanoparticles and UNCD films are studied by field emission scanning electron microscope (FESEM). Raman and electron field emission (EFE) studies reveal that the obtained UNCD films derived from electrophoresis possess the same performance as a nucleation layer obtained through the ultrasonication method. Moreover, we also demonstrate the growth of UNCD film onto Si nanowires (SiNWs) and tungsten carbide (WC) through the electrophoresis nucleation technique. Electrophoresis nucleation provides a better aligned SiNWs than ultrasonication technique. Enhanced EFE properties are also observed for UNCD nanoemitters on electrophoresis nucleated SiNWs. For the WC substrates, both ultrasonication and electrophoresis nucleations can promote the growth of UNCD films successfully. In addition, UNCD films on electrophoresis nucleated WC substrates also shows better EFE properties.

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