Effects of nanometric plastic strain on the cantilever deflection sensitivity calibration accuracy for atomic force microscopy (AFM)-nanoindentation tests

The atomic force microscope (AFM) works by measuring the deflection of a cantilever as it is scanned over a sample. A sharp tip at the end of the cantilever is responsible for the high lateral resolution achieved with the AFM. There are several ways to measure the deflection of the cantilever. The technique used to measure the deflection of the cantilever most often dictates the mechanical complexity and stability of the instrument. Electron tunneling, interferometry and capacitive sensors have been used successfully. The most common way to measure the cantilever deflection is by means of an optical deflection detector.The piezoresistivc cantilever offers a new way to measure the deflection of the cantilever, with performances comparable to the performances of other deflection detectors, and with the advantage that the sensor is incorporated in the cantilever. This simplifies the design and operation of the microscope In particular, the piezoresistive cantilever facilitates the use and often improves the performances of an AFM when operated in ultra high vacuum (UHV), at low temperature, or when used to image large samples.

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Slip trace characterisation of Ni3Al by atomic force microscopy.

MRS Proceedings ◽

10.1557/proc-646-n5.14.1 ◽

2000 ◽

Vol 646 ◽

Cited By ~ 1

Author(s):

Christophe Coupeau ◽

Tomas Kruml ◽

Joël Bonneville

Keyword(s):

Atomic Force Microscopy ◽

Flow Stress ◽

Plastic Strain ◽

Slip System ◽

Mean Free Path ◽

Force Microscopy ◽

Atomic Force ◽

Slip Traces ◽

Octahedral Slip ◽

Increasing Temperature

ABSTRACTWe examined by atomic force microscope the slip traces produced on Ni3Al single crystals pre-deformed up to nearly 1% plastic strain at three temperatures in the anomaly domain: 293K, 500K and 720K. It is observed that, whatever the deformation temperature, the slip traces essentially belong to the primary octahedral slip system. The lengths of the slip lines become shorter and shorter with increasing temperature, while the number of dislocations that constitutes the lines is approximately constant. These results are interpreted in terms of a decreasing mean free path of the mobile dislocations when the temperature is raised. The implications of these results in the understanding of the flow stress anomaly are underscored.

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High-bandwidth multimode self-sensing in bimodal atomic force microscopy

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.7.26 ◽

2016 ◽

Vol 7 ◽

pp. 284-295 ◽

Cited By ~ 23

Author(s):

Michael G Ruppert ◽

S O Reza Moheimani

Keyword(s):

Atomic Force Microscopy ◽

Piezoelectric Layer ◽

Signal To Noise Ratio ◽

Beam Deflection ◽

Feedback Signal ◽

Phase Imaging ◽

Cantilever Deflection ◽

Force Microscopy ◽

Atomic Force ◽

A Charge

Using standard microelectromechanical system (MEMS) processes to coat a microcantilever with a piezoelectric layer results in a versatile transducer with inherent self-sensing capabilities. For applications in multifrequency atomic force microscopy (MF-AFM), we illustrate that a single piezoelectric layer can be simultaneously used for multimode excitation and detection of the cantilever deflection. This is achieved by a charge sensor with a bandwidth of 10 MHz and dual feedthrough cancellation to recover the resonant modes that are heavily buried in feedthrough originating from the piezoelectric capacitance. The setup enables the omission of the commonly used piezoelectric stack actuator and optical beam deflection sensor, alleviating limitations due to distorted frequency responses and instrumentation cost, respectively. The proposed method benefits from a more than two orders of magnitude increase in deflection to strain sensitivity on the fifth eigenmode leading to a remarkable signal-to-noise ratio. Experimental results using bimodal AFM imaging on a two component polymer sample validate that the self-sensing scheme can therefore be used to provide both the feedback signal, for topography imaging on the fundamental mode, and phase imaging on the higher eigenmode.

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A review of demodulation techniques for amplitude-modulation atomic force microscopy

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.8.142 ◽

2017 ◽

Vol 8 ◽

pp. 1407-1426 ◽

Cited By ~ 22

Author(s):

Michael G Ruppert ◽

David M Harcombe ◽

Michael R P Ragazzon ◽

S O Reza Moheimani ◽

Andrew J Fleming

Keyword(s):

Atomic Force Microscopy ◽

Amplitude Modulation ◽

High Speed ◽

Performance Metrics ◽

Processing System ◽

Digital Processing ◽

Cantilever Deflection ◽

Force Microscopy ◽

Atomic Force ◽

Frequency Components

In this review paper, traditional and novel demodulation methods applicable to amplitude-modulation atomic force microscopy are implemented on a widely used digital processing system. As a crucial bandwidth-limiting component in the z-axis feedback loop of an atomic force microscope, the purpose of the demodulator is to obtain estimates of amplitude and phase of the cantilever deflection signal in the presence of sensor noise or additional distinct frequency components. Specifically for modern multifrequency techniques, where higher harmonic and/or higher eigenmode contributions are present in the oscillation signal, the fidelity of the estimates obtained from some demodulation techniques is not guaranteed. To enable a rigorous comparison, the performance metrics tracking bandwidth, implementation complexity and sensitivity to other frequency components are experimentally evaluated for each method. Finally, the significance of an adequate demodulator bandwidth is highlighted during high-speed tapping-mode atomic force microscopy experiments in constant-height mode.

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Correlation of Atomic Force Microscopy Tapping Forces to Mechanical Properties of Lipid Membranes

Volume 5: 6th International Conference on Micro- and Nanosystems; 17th Design for Manufacturing and the Life Cycle Conference ◽

10.1115/detc2012-70233 ◽

2012 ◽

Author(s):

Nicole Shamitko-Klingensmith ◽

Kelley M. Wambaugh ◽

Kathleen A. Burke ◽

George J. Magnone ◽

Justin Legleiter

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Lipid Membranes ◽

Scanning Probe ◽

Second Derivative ◽

Time Resolved ◽

Cantilever Deflection ◽

Force Microscopy ◽

Atomic Force ◽

Mode Atomic Force Microscopy

There is considerable interest in measuring, with nanoscale spatial resolution, the physical properties of lipid membranes because of their role in the physiology of living systems. Due to its ability to nondestructively image surfaces in solution, tapping mode atomic force microscopy (TMAFM) has proven to be a useful technique for imaging lipid membranes. However, further information concerning the mechanical properties of surfaces is contained within the time-resolved tip/sample force interactions. The tapping forces can be recovered by taking the second derivative of the cantilever deflection signal and scaling by the effective mass of the cantilever; this technique is referred to as scanning probe acceleration microscopy. Herein, we describe how the maximum and minimum tapping forces change with surface mechanical properties. Furthermore, we demonstrate how these changes can be used to measure mechanical changes in lipid membranes containing cholesterol.

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Atomic Force Microscopy and Related Techniques: Introduction, Instrumentation and Application to Polymeric Materials

Microscopy and Microanalysis ◽

10.1017/s1431927600024235 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 822-823

Author(s):

Inga Holl Musselman

Keyword(s):

Atomic Force Microscopy ◽

Polymeric Materials ◽

Polymer Surfaces ◽

Nanometer Scale ◽

Important Class ◽

Semiconducting Materials ◽

Contact Mode ◽

Cantilever Deflection ◽

Force Microscopy ◽

Atomic Force

Atomic force microscopy (AFM) was introduced in 1986 by Binnig, Quate and Gerber. In this method, a sample is scanned beneath a small, sharp silicon or silicon nitride probe attached to the apex of a flexible cantilever. Cantilever deflection is measured to give height information corresponding to the sample topography. Since AFM relies on tip-sample force interaction, the technique can be applied to insulators as well as to conducting and semiconducting materials. AFM therefore extends local probe studies to an important class of materials which can be difficult to investigate by electron microscopy and spectroscopy techniques owing to problems with sample charging. Among other materials, AFM has been used extensively to characterize the morphology, roughness, nanostructure, chain packing and conformation of polymer surfaces at the nanometer scale.Early AFM studies of polymers were conducted in the contact mode and included the investigation of polymerized monolayers of n-(2-aminoethyl)-10,12-tricosadiynamide (AE-TDA) and poly(octadecylacrylate) (PODA) at submonolayer coverage.

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