教師資料查詢 | 類別: 期刊論文 | 教師: 林諭男 I-nan Lin (瀏覽個人網頁)

標題:Improvement in plasma illumination properties of ultrananocrystalline diamond films by grain boundary engineering
學年102
學期1
出版(發表)日期2013/08/01
作品名稱Improvement in plasma illumination properties of ultrananocrystalline diamond films by grain boundary engineering
作品名稱(其他語言)
著者K. J. Sankaran; K. Srinivasu; Chen, H. C.; Dong, C. L.; Leou, K. C.; Lee, C. Y.; Tai, N. H.; Lin, I. N.
單位淡江大學物理學系
出版者College Park: American Institute of Physics
著錄名稱、卷期、頁數Journal of Applied Physics 114(5), 054304(11pages)
摘要Microstructural evolution of ultrananocrystalline diamond (UNCD) films as a function of substrate temperature (TS) and/or by introducing H2 in Ar/CH4 plasma is investigated. Variation of the sp 2 and sp 3 carbon content is analyzed using UV-Raman and near-edge X-ray absorption fine structure spectra. Morphological and microstructural studies confirm that films deposited using Ar/CH4 plasma at low TS consist of a random distribution of spherically shaped ultra-nano diamond grains with distinct sp 2-bonded grain boundaries, which are attributed to the adherence of CH radicals to the nano-sized diamond clusters. By increasing TS, adhering efficiency of CH radicals to the diamond lattice drops and trans-polyacetylene (t-PA) encapsulating the nano-sized diamond grains break, whereas the addition of 1.5% H2 in Ar/CH4 plasma at low TS induces atomic hydrogen that preferentially etches out the t-PA attached to ultra-nano diamond grains. Both cases make the sp 3-diamond phase less passivated. This leads to C2 radicals attaching to the diamond lattice promoting elongated clustered grains along with a complicated defect structure. Such a grain growth model is highly correlated to explain the technologically important functional property, namely, plasma illumination (PI) of UNCD films. Superior PI properties, viz. low threshold field of 0.21 V/μm with a high PI current density of 4.10 mA/cm2 (at an applied field of 0.25 V/μm) and high γ-coefficient (0.2604) are observed for the UNCD films possessing ultra-nano grains with a large fraction of grain boundary phases. The grain boundary component consists of a large amount of sp 2-carbon phases that possibly form interconnected paths for facilitating the transport of electrons and the electron field emission process that markedly enhance PI properties.
關鍵字
語言英文
ISSN0021-8979;1089-7550
期刊性質國外
收錄於
產學合作
通訊作者
審稿制度
國別美國
公開徵稿
出版型式,電子版,紙本
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