Kelvin probe force microscopy (KPFM) is a useful technique for simultaneously visualizing topography and contact potential difference (CPD). Although frequency-modulation (FM) KPFM has high spatial resolution and sensitivity, it is not readily applicable to measuring large protrusions owing to the instability of the feedback condition. Here we investigate the combined use of amplitude-modulation and FM for tip-sample distance control and electrostatic force detection, respectively. The proposed method enabled simultaneous acquisition of topography and CPD images of gold nanoparticles on a Nb-doped TiO 2 (100) surface. The effect of the tip shape and tilt angle on the CPD images is also discussed.

中文翻译：

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攻丝模式下对具有大突起的表面进行调频开尔文探针力显微镜

开尔文探针力显微镜（KPFM）是同时可视化地形和接触电势差（CPD）的有用技术。尽管调频（FM）KPFM具有很高的空间分辨率和灵敏度，但由于反馈条件的不稳定性，因此不适用于测量大的突起。在这里，我们研究了振幅调制和FM分别用于尖端采样距离控制和静电力检测的组合使用。所提出的方法能够在Nb掺杂的TiO 2（100）表面上同时获取金纳米颗粒的形貌和CPD图像。还讨论了尖端形状和倾斜角度对CPD图像的影响。