Sensitivity of near-edge x-ray absorption fine structure spectroscopy to ion beam damage in diamond films
Sensitivity of near-edge x-ray absorption fine structure spectroscopy to ion beam damage in diamond films
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DOI：
10.1063/1.371346
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发表时间：
1999-10-15
影响因子：
3.2
通讯作者：
Dujardin, G
中科院分区：
文献类型：
--
作者：
Laikhtman, A;Gouzman, I;Dujardin, G
本文研究了近边X射线吸收精细结构谱（NEXAFS）对多晶金刚石薄膜中离子诱导缺陷的灵敏度。氢化膜的离子轰击是在室温下使用30 keV的离子进行的，剂量范围从2 × 10（13）离子/cm（2），产生局部点缺陷，到2 × 10（15）离子/cm（2），这导致金刚石表面几乎完全非晶化。俄歇电子能谱测量是不敏感的最低注入剂量引起的修改。而部分电子产额（PEY）NEXAFS测量，应用在表面和体敏感模式，分别使用35，15，和8 eV的二次电子，揭示了形成的缺陷结构和逐渐恶化的金刚石在近表面区域。从使用15 eV二次电子测量的PEY NEXAFS光谱，测量C（1 s）结合能的位置。使用450 eV的入射光子能量测量样品的X射线光电子能谱。结果表明，注入样品中C（1 s）的结合能发生了0.6 ~ 1 eV的正移，表明金刚石向无序碳转变。NEXAFS光谱对低剂量离子注入引起的点缺陷的高灵敏度反映在金刚石芯激子峰强度的急剧降低和在C（1 s）-pi* 跃迁下方的前边缘区域出现新的光谱特征。根据金刚石的电子结构，对离子注入薄膜的NEXAFS谱进行了分析。(C)1999年美国物理学会。[S0021-8979（99）02220-3]。
In the present work, we study the sensitivity of the near-edge x-ray absorption fine structure (NEXAFS) spectroscopy to ion induced defects in polycrystalline diamond films. The ion bombardment of hydrogenated films is performed using 30 keV Xe+ ions at room temperature for doses ranging from 2 x 10(13) ions/cm(2), producing local point defects, to 2 x 10(15) ions/cm(2), which results in almost complete amorphization of the diamond surface. Auger electron spectroscopy measurements are not sensitive to the modifications induced by the lowest implantation dose. Whereas partial electron yield (PEY) NEXAFS measurements, applied in surface and bulk-sensitive modes, using 35, 15, and 8 eV secondary electrons, respectively, reveals the formation of a defective structure and gradual deterioration of diamond in the near-surface region. From PEY NEXAFS spectra measured using 15 eV secondary electrons, the position of C(1s) binding energy is measured. The x-ray photoelectron spectra of the samples were measured using an incident photon energy of 450 eV. It is found that the C(1s) binding energy in the implanted samples has a positive shift of 0.6-1 eV, which is indicative of transformation of diamond to disordered carbon. The high sensitivity of NEXAFS spectroscopy to point defects induced by the low dose ion implantation was reflected by a sharp reduction in the intensity of the diamond core exciton peak and by the appearance of a new spectral feature in the pre-edge region, below the C(1s)-pi* transition. Analysis of the NEXAFS spectra of ion implanted films is performed on the basis of the electronic structure of diamond. (C) 1999 American Institute of Physics. [S0021-8979(99)02220-3].