Hydrogen termination and electron emission from CVD diamond surfaces: a combined secondary electron emission, photoelectron emission microscopy, photoelectron yield, and field emission study
Hydrogen termination and electron emission from CVD diamond surfaces: a combined secondary electron emission, photoelectron emission microscopy, photoelectron yield, and field emission study
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DOI：
10.1016/s0925-9635(99)00279-4
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发表时间：
2000-04-01
影响因子：
4.1
通讯作者：
Ley, L
中科院分区：
文献类型：
--
作者：
Cui, JB;Ristein, J;Ley, L
研究了氢终止对 CVD 金刚石表面电子发射特性的影响。在无氢和氢封端表面上比较了三种电子发射过程，即二次电子发射（SEM）、光电子发射和保持发射。采用电子束刺激解吸来从金刚石表面解吸氢，并在其他被氢覆盖的表面上形成无氢区域的图案。对于所研究的发射过程，与无氢表面相比，氢终止区域产生强烈的电子发射。特别是，通过 SEM 和光电子发射显微镜 (PEEM)，无氢图案的成像具有相当的对比度。这表明金刚石表面的氢终止通过降低金刚石表面的电子亲和势来降低电子发射的能垒。同一 CVD 金刚石膜的氢化部分和无氢部分之间场发射起始的巨大差异证实了这一点。产率光谱进一步证明，氢化过程降低了金刚石间隙以下的电子发射阈值。 (C) 2000 Elsevier Science S.A. 保留所有权利。
The effect of hydrogen termination on the electron emission properties of CVD diamond surfaces is investigated. Three kinds of electron emission process, namely secondary electron emission (SEM), photoelectron emission, and held emission are compared on hydrogen free and hydrogen terminated surfaces. Electron beam stimulated desorption was employed to desorb hydrogen from the diamond surface and to pattern H-free areas on otherwise H-covered surfaces. The hydrogen terminated areas give strong electron emission in contrast to the hydrogen free surfaces for an emission processes studied. In particular, the hydrogen free patterns are imaged with comparable contrast by SEM and photoelectron emission microscopy (PEEM). This indicates that the hydrogen termination on diamond surfaces reduces the energy barrier for electron emission by lowering the electron affinity of diamond surface. This is confirmed by a drastic difference in the onset for field emission between the hydrogenated and hydrogen free parts of the same CVD diamond film. It is further demonstrated by yield spectroscopy that the threshold for electron emission below the gap of diamond is lowered by the hydrogenation process. (C) 2000 Elsevier Science S.A. All rights reserved.