Positron annihilation on the surfaces of single crystals of Si, SiO2, graphite and Cu

摘要：

Slow positron beam technique has been applied to measure the Doppler broadening spectra for single crystals of Cu, SiO2, graphite, virgin Si, and Si without oxide film. The results show that the Cu ratio curve shows a high peak due to Cu having 10 electrons in the 3d shells. The ratio curve of SiO2 is higher than that of graphite. For the single crystal of Cu, SiO2, graphite, and Si without oxide film, the S (W) parameters decrease (increase) as positron implantation energy increasing. Defects on the surface lead to higher S (lower W) value. For the virgin Si and the thermally grown SiO2-Si samples, the S (W) parameters increase (decrease) as positron implantation energy increasing. It can be due to Si atom at surface, with two dangling bonds, tend to form silicon oxide with O. The W parameter for the single crystal of Cu is relatively high as compared with that of the single crystals of SiO2 and graphite.

关键词： Surface silicon ozide defect positron annihilation

作者: Deng Wen Yue Li Li Yu-Xia Cheng Xu-Xin Wei Ya-Qin Huang Yu-Yang

作者单位: Department of Physics,Guangxi University,Nanning 530004,P.R.China

会议类型: 国际会议

会议名称: 第九届国际正电子与正电子素国际会议(9th International Workshop on Positron and Positronium Chemistry)(PPC–9)

会议地点: 武汉

会议语种:英文

页码: 152-154

在线出版日期: 2008-05-11（万方平台首次上网日期，不代表论文的发表时间）