奈米碳管鍍上寬能隙材料及其場發射顯示器的應用

CARBON NANOTUBES COATED WITH WIDE BAND GAP MATERIALS FOR APPLICATION ON FIELD EMISSION DISPLAY

邱維彥(Wei-yan Chiu)

指導教授 ： 施文欽

大同大學/電機資訊學院/光電工程研究所/碩士(2007年)

摘要

本論文主要是利用熱化學氣相沉積法在乙炔和氨氣的混合氣體中成長奈米碳管，藉由實驗參數的控制，我們可以改變奈米碳管的形貌和品質，而場發射特性也隨著奈米碳管的形貌和品質之改變而有所不同。在二極式的架構下，陽極和陰極的間隙約為300 μm，我們在1.25 V/μm電場強度下可獲得1 mA/cm2的電流密度。
臨場利用氨氣加熱後處理奈米碳管，經由顯微拉曼光譜量測的結果，D-band的半高寬由原來的60 ~ 61 cm-1降低到32 ~ 38 cm-1左右，可能是奈米碳管壁上的非晶碳被去除了。
由於二氧化矽具有低介電常數（3.9）、寬能隙（9 eV）及小電子親和力（0.6 ~ 0.8 eV）的性質，我們利用射頻磁控濺鍍法沉積二氧化矽薄膜於奈米碳管上，目的是希望利用二氧化矽薄膜做為奈米碳管的保護層，以提高陰極材料的生命週期。我們在有經後處理的奈米碳管上沉積10 nm的SiO2，其生命週期可達30 hr，此結果有利於將來場發射顯示器的應用。

關鍵字

奈米碳管 ； 場發射顯示器 ； 寬能隙材料 ； 二氧化矽

並列摘要

In this search, the vertically aligned carbon nanotubes (CNTs) are synthesized with high density on iron-deposited silicon substrate using mixtures of C2H2 and NH3 gases by thermal chemical vapor deposition. CNTs can be controlled by changing the growth parameters and the field emission properties are changed by the morphology and quality of CNTs. The emission current density is 1 mA/cm2 at an applied field of about 1.25 V/μm with the diode structure of 300 μm gap.
The D-band FWHM value of CNTs post-treated in NH3 by heat treatment are reduced from 61.50 cm-1 to 32.72 cm-1, it maybe removed the amorphous carbon on the surface of CNTs.
SiO2 has low static dielectric constant (3.9), wide band gap (9 eV), and small electron affinity (0.6 ~ 0.8 eV) properties. The SiO2 films are deposited by RF magnetron sputtering. We hope SiO2 act as a protective layer of CNTs and increase the lifetime of CNTs during field emission. The lifetime of SiO2 film deposited on post-treated CNTs with thickness of 10 nm was improved to 30 hr. This result will be advantageous to application on field emission display.

並列關鍵字

carbon nanotube ； field emission display ； wide band gap materials ； silicon oxide

參考文獻

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