鑽石薄膜複合垂直寡層石墨之場發射特性研究

Field Emission Characteristic Study on Vertical Few-layer Graphite/Diamond Composite Film

曾柏棠(Tseng, Po Tang)

指導教授 ： 蔡宏營

國立清華大學/工學院/動力機械工程學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00043

摘要

本研究目的在於製作出高場發射效應之鑽石複合垂直寡層石墨奈米針尖形貌，透過場發射效應低耗能及高功率優點，可應用於未來更薄型之面板或製作良好散熱元件。
研究方法透過製作八角錐體微奈米鑽石針尖薄膜，並於鑽石奈米針尖上成長垂直寡層石墨加強其場發射效應及使用壽命。在成長鑽石及垂直寡層石墨的過程中，改變通入氮氣的多寡提高鑽石針尖複合垂直寡層石墨形貌之場發射效應。以拉曼光譜儀量測鑽石及垂直寡層石墨性質，掃描式電子顯微鏡觀察鑽石針尖及垂直寡層石墨形貌，並測量其場發射效應。
本研究首次提出以微奈米鑽石複合垂直寡層石墨的方式製作八角錐體針尖形貌之創新針尖陣列，透過鑽石的高穩定性增加場發射元件的使用壽命及垂直寡層石墨的高深寬比與良好電性增加場發射效應。所成長之鑽石針尖薄膜為微米鑽石及超奈米鑽石，垂直寡層石墨為交錯片狀且其內層由鑽石結構組成為以往研究未曾發現的形式。
本研究中以N2/H2/CH4 = 40/80/20所成長之鑽石複合垂直寡層石墨針尖擁有2.60 V/μm低起始電場及1921場增益因子，並擁有高穩定壽命，展現出優異之場發射特性。

關鍵字

場發射 ； 垂直寡層石墨 ； 微奈米鑽石 ； 八角錐體針尖 ； 場增益因子

並列摘要

The purpose of this study is to produce the diamond tip arrays composite vertical few-layer graphite with high field emission effect. Because of its lower energy cost and high power advantages. It can be applied to thin the panel or make better cooling components.
The diamond tip arrays with octagonal cone are formed by microwave plasma enhanced chemical vapor deposition (MPCVD) on silicon. Through the diamond and vertical few-layer graphite deposition, change the amount of nitrogen which leads to improve the diamond tip field emission. The diamond tip arrays and vertical few-layer graphite morphology are examined by Raman spectroscopy and scanning electron microscopy (SEM), respectively. The field emission effect with different diamond composite vertical few-layer graphite arrays are examined by field emission meter.
The research first proposed the diamond tip composite vertical few-layer graphite structure with novel octagonal cone array to improve the field emission effect and lifetime because of the high pitch height ratio of vertical few-layer graphite and the high stability of diamond. The microcrystalline and ultrananocrystalline diamond are growth in this research. Besides, the staggered arrangement of vertical few-layer graphite and the diamond structure growth inside the vertical graphite flake is different from previous studies.
In this study, the diamond tip arrays composite vertical few-layer graphite growth by N2/H2/CH4 = 40/80/20 shows good filed emission stability and high field emission characteristics with low turn-on field of 2.60 V/μm and field enhancement factor of 1921.

並列關鍵字

field emission ； vertical few-layer graphite ； microcrystalline and ultrananocrystalline diamond ； octagonal cone ； field enhancement factor

參考文獻

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