利用I-Z曲线的STM“接触”模式的电学测量和表面改性研究  

Electrical characteristic test and surface modification in “Contact” mode of STM using I-Z curve

作　　者：李旭[1] 严学俭[1] 邱伟民[1] 张群[1] 王伟军[1] 华中一[1] 

机构地区：[1]复旦大学材料科学系,上海200433

出　　处：《电子显微学报》2003年第2期180-184,共5页Journal of Chinese Electron Microscopy Society

摘　　要：利用STM对金属有机络合物电双稳材料Ag TCNQ薄膜进行电学性质的表征与改性 ,在针尖强电场的作用下 ,当电压达到某一阈值后薄膜从高阻态跃迁至低阻态 ,这两种高低阻态分别定义为一个存储单元的“0”与“1”状态。本文考虑到在STM的常规恒流工作模式下 ,针尖与样品之间的隧道结对于电学性质的表征与改性具有影响。为此测量隧道电流It 对隧道结宽度Z的依赖关系I Z曲线 ,从而确定针尖刚好接触样品的接触点 ,利用STM进行了针尖与样品“接触式”的电学测量和表面电学改性研究 。Characterization and surface modification of electric property have been carried out on the organmetallic complex Ag-TCNQ thin film by scanning tunneling microscope (STM). The resistance of an organmetallic complex Ag-TCNQ thin film will be changed from a high resistance state to a low resistance state when the bias voltage between the tip of STM and the bottom electrode was in excess of a certain threshold voltage. The two states can be defined as “0” and “1” of a memory unit respectively. In order to avoid the effect of tunnel junction between the tip and the sample, which isn't the intrinsic property of the material, the I-Z curve was measured and the point at which the tip just contacts with the surface of the Ag-TCNQ thin film was found. Then a test and a modification in so-called “contact” mode of STM have been carried out, and the result was compared with that in the conventional mode.

关 键 词：有机材料 电双稳态 隧道结 表面改性 隧道电流 扫描隧道显微镜 

分 类 号：TM933.4[电气工程—电力电子与电力传动]