炭素系材料表面からの2次電子放出と表面組成

抄録

A new aspect of problems caused by secondary electron emission from a solid surface irradiated by energetic particles has recently emerged in some fields of science and industry. In a particle accelerator, for example, a problem of electron cloud instability has emerged. In this report, we focused on secondary electron emission from carbon materials to be compared with already reported some metals and TiN_x materials. DLC (Diamond Like Carbon), diamond (110), amorphous carbon, HOPG (Highly Oriented Pyrolytic Graphite) and isotropic graphite were prepared to carry out a series of measurements of secondary electron yields (SEYs) and in-situ surface characterizations by X-ray photoelectron spectroscopy (XPS). The measurements were done under the surface conditions as follows; as-received, after electron beam irradiation and after sputter cleaning with Ar⁺ ion beam. The maximum SEYs in its primary electron energy dependence of carbon materials were found to be around 1 after sputter cleaning. These low SEYs for the carbon materials verified our hypothesis that graphitization at the surfaces by electron beam irradiation in UHV was a reason for decreases of SEYs for the metals and TiN_x materials.