Characterization and electrochemical properties of CF₄ plasma-treated boron-doped diamond surfaces

详细信息    查看全文

• 作者：Takeshi Kondo ; Hiroyuki Ito ; Kazuhide Kusakabe ; Kazuhiro Ohkawa ; Kensuke Honda ; Yasuaki Einaga ; Akira Fujishima ; Takeshi Kawai
• 关键词：Diamond film ; Surface characterization ; Electrochemical
• 刊名：Diamond and Related Materials
• 出版年：2008
• 出版时间：January 2008
• 年：2008
• 卷：17
• 期：1
• 页码：48-54
• 全文大小：707 K

文摘

The effect of CF₄ plasma etching on diamond surfaces, with respect to treatment time, was investigated using scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electrochemical measurements. SEM observations and Raman spectra indicated an increase in surface roughening on a scale of 10–20 nm, and an increase in crystal defect density was apparent with treatment time in the range of 10 s to 30 min. In contrast, alteration of the diamond surface terminations from oxygen to fluorine was found to be rather rapid, with saturation of the F/C atomic ratio estimated from XPS analysis after treatment durations of 1 min and more. The redox kinetics of Fe(CN)₆^3−/4− was also found to be significantly modified after 10 s of CF₄ plasma treatment. This behavior shows that C–F terminations predominantly affect the redox kinetics compared to the effect on the surface roughness and crystal defects. The double-layer capacitance (C_dl) of the electrolyte/CF₄ plasma-treated boron-doped diamond interface was found to show a minimum value at 1 min of treatment. These results indicate that a short-duration CF₄ plasma treatment is effective for the fabrication of fluorine-terminated diamond surfaces without undesirable surface damage.