用X光激发电子能谱(XPS)分析技术对Si3N4/SiO2/Si双界面系统经6O^Co电离辐照前后处于纯Si态的一级等离激元(定位于B.E.116.95eV)、处于SiO2态的一级等离激元(定位于B.E.122.OeV)和处于Si3N4态的一级等离激元(定位于B.E.127.OeV)进行了研究。实验结果显示:存在一个由Si3N4态等离激元和SiO2态等离激元构成的界面及由SiO2态等离激元和Si态等离激元构成的界面,在电离辐射的作用下,SiO2态-Si3N4态等离激元界面区中心向Si3N4态表面方向推移,同时SiO2态/Si3N4态等离激元界面区亦被展宽;电离辐照相当程度地减少位于SiO2态-Si态界面至Si衬底之间SiO2态的一级等离激元的浓度:同时偏置电场对SiO2/Si界面等离激元有显著作用。文中就实验现象以光电子能损进行了机制分析。
The first level plasmons of Si in pure Si state, SiO2 state and Si3N4 state (corresponding to bonding energy of 116.95, 122.0 and 127.0 eV respectively) were investigated directly with X-ray Photoelectron Spectroscopy (XFS) before and after 60^Co irradiation. The experimental results demonstrate that there exist two interfaces, one consists of plasmons of Si in Si3N4 state and in SiO2 state, while the other is made of plasmons of Si in pure Si state and in SiO2 state. When the Si3N4/SiO2/Si samples were irradiated by 60^Co, the interface at Si3N4/SiO2 was extended and at the same time the center of this interface moved towards the surface of Si3N4. The concentration of plasmons in SiO2 state was decreased at the SiO2/Si interface, and effects of radiation bias field on plasmons in the SiO2/Si interface were observable. Finally, the mechanism of experimental results is analyzed by the quantum effect of plasmons excited by photoelectrons.