Photovoltaic characterization of semiconductors with STM
Photovoltaic characterization of semiconductors with STM
复制标题
使用 STM 进行半导体光伏表征
DOI：
10.1007/s003390051277
复制
发表时间：
1998
期刊：
影响因子：
--
通讯作者：
R. Neumann
中科院分区：
文献类型：
--
作者：
T. Hagen;S. Grafström;J. Kowalski;R. Neumann
抽象的。表面光电压（SPV）提供有关半导体表面电子结构的信息。过去已经实现了几种使用 STM 测量 SPV 的方案，使用连续照明和调制照明。在后一种情况下，信号还包含由于热膨胀和尖端样品杂散电容而产生的影响。对于 Si (111)-(7x7) 等金属表面的测量，我们采用电位法：电导率 dI/dV 用于距离控制，而第二个反馈回路调整偏置电压以实现零直流电流，从而提供 SPV 的直接测量。形貌和 SPV 同时连续成像。我们展示了用这种方法获得的数据以及在调制照明下观察到的竞争效应的实验分析。
Abstract. Surface photovoltage (SPV) provides information on the electronic structure of semiconductor surfaces. Several schemes for measuring SPV with the STM have been realized in the past, using both continuous and modulated illumination. In the latter case the signal also contains contributions due to thermal expansion and tip-sample stray capacitance. For measurements on metal-like surfaces such as Si (111)-(7x7) we apply a potentiometric method: the conductivity dI/dV is used for distance control, while a second feedback loop adjusts the bias voltage for zero DC current, thus providing a direct measure of the SPV. Topography and SPV are imaged simultaneously and continuously. We present data obtained with this method as well as an experimental analysis of the competing effects observed under modulated illumination.