层状材料的总电流谱研究  

TCS STUDY ON LAYERD MATERIAL

作　　者：施蓓培[1,2] 潘星龙[1,2] 诸葛健 华中一 

机构地区：[1]复旦大学真空物理研究室 [2]中国科学院北京真空物理实验室

出　　处：《真空科学与技术学报》1990年第2期119-121,共3页Chinese Journal of Vacuum Science and Technology

摘　　要：总电流谱(TCS)是一种新的表面分析手段。我们用自制的谱仪研究了多晶石墨及热解石墨(HOPG)的TCS谱图,首先发现了多晶石墨存在有表面等离子激发峰。Total Current Spectroscopy (TCS) is a new tool for surface analysis. This technique has already found application in studies of work function, chemi-physisorption, epitaxy, interbaud transition, DOS, plasmon, etc.In TCS, a beam of low energy electrons (0-30eV) with constant current is bombarded onto the sample surface, and the variation of the transmission current from the sample (or the reflection current which is the difference between the incident current and the transmission current) with incident electron energy is measured. Due to the interaction with the sample surface, incident electrons will undergo some characteristic energy-loss processes. when their energy reach certain thresholds, resulting in the variation of the transmission current. It is found that these energy-loss processes are directly related to the surface state of the sample (interband transition, plasmon, exciton, surface resonance, etc), so TCS is employed as a tool for surface analysis.A TCS setup has been built in our laboraty. It is built into a continuously-pumping vacuum chamber reaching a base pressure of (3-6)×10^(-7)Pa. An Argon ion-gun in the same chamber is used for surface cleaning. The cleanness of the sample is monitored by the AES in the system. The TCS spectra of some layered materials (poly-crystslline graphite, and HOPG) are obtained in this system. The surface plasmon peak of poly-crystalline graphite is observed for the first time.Finally, vat(?)ous factors affecting the fine structure anh the energy resolution of the TCS setup are discussed.

关 键 词：电流谱 激发峰 层状材料 锁相放大器 热解石墨 表面分析 射束 加速电压 等势线 带间跃迁 

分 类 号：TB7-55[一般工业技术—真空技术]