扫描隧道显微镜探针的制备与修饰的方法研究

Preparation and Modification of the Probes for Scanning Tunneling Microscope

基于改进的电化学腐蚀法,来制备扫描隧道显微镜的探针。在探针针尖形成的瞬间,通过断开电解液和针尖的直接接触有效地解决了尖端原子被残余电量二次腐蚀的问题;并利用液膜表面张力作用对探针进行修饰,来提高其针尖的尖锐程度。将修饰后的探针用于STM扫描,得到了清晰的Ga As(001)表面原胞排列图像,结果表明该方法所修饰的探针可用于低维半导体材料表面形貌和表面重构的研究。

An improved electrochemical etching method was applied to prepare the scanning tunneling micro- scope probe. In the improved process, once the tips were formed, by disconnecting the connection between the tip and solution, it can effectively avoid the atoms on tip apex suffering the secondary corrosion by the residual current. And the probe can be modified by surface tension of the liquid film to improve its tip sharpness. Then the modified probe was applied to characterizing the GaAs surface, the resulted high-resolution images confirmed the high quality of tips. Therefore, the probes modified by this method can be utilized for studying the surface morphology and reconstructions of low dimensional semiconductor materials.