Atomic force microscopy with inherent disturbance suppression for nanostructure imaging

Abstract

Scanning probe imaging is often limited by disturbances, or mechanical noise, from the environment that couple into the microscope. We demonstrate, on a modified commercial atomic force microscope, that adding an interferometer as a secondary sensor to measure the separation between the base of the cantilever and the sample during conventional feedback scanning can result in real-time images with inherently suppressed out-of-plane disturbances. The modified microscope has the ability to resolve nanometre-scale features in situations where out-of-plane disturbances are comparable to, or even several orders of magnitude greater than, the scale of the topography. We present images of DNA in air from this microscope in tapping mode without vibration isolation, and show improved clarity using the interferometer as the imaging signal. The inherent disturbance suppression approach is applicable to all scanning probe imaging techniques.

An ultrastable platform for the study of single-atom chains

“…13 Scanning provides the ability to image the electrode surface, 19 and the flexibility to form junctions at various locations on the flat surface without a return to room temperature. 24 In addition, there have also been experiments in which nanoscale junctions are formed and broken within a transmission electron microscope. The advantages of this approach are rapid experimentation and the ability to calibrate the probe displacement by scanning over nanometer-scale step height standards.…”

Surface Roughness and Grain Size Characterization of Annealing Temperature Effect For Growth Gallium and Tantalum Doped Ba_0.5 Sr_0.5TiO₃Thin Film

“…Instead of tunneling current, an AFM detects interatomic forces that occur between a cantilever probe tip and a sample. Normal imaging forces are in the 1 -50 nanonewton range and cantilever deflections of less than 0.1 nm can be detected (nanoscale) [15][16][17][18][19][20][21].…”

Athermalization in atomic force microscope based force spectroscopy using matched microstructure coupling

“…When the cantilever should be engaged on the sample for the entire experiment, the referencing can be done by reading the deflection of a reference sensor. The reference sensor, which provides distance information from the cantilever substrate-to-sample can simply be another cantilever next to the measurement one, 10,11 an interferometer, 12 or an electrostatic sensor. 4 The reference sensor provides information for compensation of drift in distance from cantilever plane to sample substrate.…”

“…14 Maintaining the set peak force without the need for an external driver or feedback is a unique capability with the introduced approach when compared to the previously demonstrated methods. 4,[10][11][12] Note that the cantilever still bends, and there is a shift in zero-force level set for the cantilever. This can be corrected by reading the displacement of the membrane.…”