摘要
本文基于扫描探针显微镜(SPM)建立了微区电容的低频测量系统,最小测量电容为30aF,工作频率为20～100kHz。试验测量了SPM导电针尖与金属样品之间的电容Ctip与它们之间的距离z关系曲线,并同时通过光学系统测量了针尖的关于频率的一次受力信号Fw与z的关系曲线。推导了两种测量方法所获曲线的内在关系,并获得了针尖与样品的表面势之差。并且,利用此系统测量了Al0.3Ga0.7N/GaN薄膜的微区C-V曲线,获得和宏观C-V曲线趋势一致的结果。
It＇s present in the paper that a system measuring micro-area capacitance with a low frequency method is established on the scanning probe microscopy（SPM）. The smallest capacitance measured is 30 aF, and the system can work between 20 to 100 kHz. A curve of the capacitance Ctip between the AFM tip and metal depending on their distance z is measured, and at the same time, so do with a curve of the first-order force single Fw of frequency depending on z. We confirm the relationship of the two curves with different method after a comparison, and calculate out the difference of the surface potential between the tip and sample. At the last, we get the micro-area C-V curve of Al0.3Ga0.7N/GaN thin film. It has the same trend with the macroscopic C-V curve.
出处
《电子测量技术》
2009年第2期163-165,169,共4页
Electronic Measurement Technology
