Characterization of heavily boron-doped diamond films
Characterization of heavily boron-doped diamond films
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DOI：
10.1016/0925-9635(96)00539-0
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发表时间：
1996-11-01
影响因子：
4.1
通讯作者：
Lam, YW
中科院分区：
文献类型：
--
作者：
Zhang, RJ;Lee, ST;Lam, YW
采用透射电子显微镜（TEM）、二次电子显微镜、拉曼光谱、霍尔效应和电流电压测量等方法研究了热丝辅助化学气相沉积法制备的掺硼多晶金刚石薄膜。金刚石薄膜的晶粒尺寸随着薄膜电阻率的减小而减小。拉曼光谱随薄膜电阻率的变化有很大的变化。1332 cm（-1）处的区中心光声子线随薄膜电阻率的降低而下移减小，在电阻率最低的样品中甚至消失。另一方面，在465 cm（-1）和1220 cm（-1）附近出现宽峰，其强度随电阻率的降低而增加。我们认为这些现象是由于薄膜中含有重硼而破坏了拉曼散射的k=0选择规则。透射电镜研究表明，所有薄膜均为立方金刚石结构。没有boron-car;在这些薄膜中发现了Bon化合物。这一发现与拉曼结果一致，观察到迁移率增加和非价带传导。在缺陷研究中，发现孪晶是这些薄膜的主要特征，并且随着薄膜电阻率的降低，位错密度增加。
A series of boron-doped polycrystalline diamond films grown by hot-filament-assisted chemical vapor deposition was studied with transmission electron microscopy (TEM), secondary-electron microscopy, Raman spectroscopy, Hall-effect and current-voltage measurements. The grain size of the diamond films decreased as the resistivity of the films decreased. A drastic change of the Raman spectra with the film resistivity was observed. The zone-center optical phonon line at 1332 cm(-1) downnshifted and decreased as the film resistivity decreased, and even disappeared in the sample with the lowest resistivity. On the other hand, broad peaks around 465 cm(-1) and 1220 cm(-1) appeared and their intensity increased with decreasing resistivity. We attributed these phenomena to the breakdown of the k=0 selection rule of the Raman scattering owing to the heavy boron incorporation in the film. A TEM study showed that all the films were of the cubic diamond structure. No boron-car;bon compound was found in these films. This finding agreed well with the Raman result Increased mobility and non-valence-band conduction were observed. As to the defect study, twinning was found to be the dominant feature in these films, and an increase of dislocation density was also observed with decreasing resistivity of the films.