Subatomic deformation driven by vertical piezoelectricity from CdS ultrathin films

Driven by the development of high-performance piezoelectric materials, actuators become an important tool for positioning objects with high accuracy down to nanometer scale, and have been used for a wide variety of equipment, such as atomic force microscopy and scanning tunneling microscopy. However, positioning at the subatomic scale is still a great challenge. Ultrathin piezoelectric materials may pave the way to positioning an object with extreme precision. Using ultrathin CdS thin films, we demonstrate vertical piezoelectricity in atomic scale (three to five space lattices). With an in situ scanning Kelvin force microscopy and single and dual ac resonance tracking piezoelectric force microscopy, the vertical piezoelectric coefficient (d33) up to 33 pm·V−1 was determined for the CdS ultrathin films. These findings shed light on the design of next-generation sensors and microelectromechanical devices.

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Heterogeneous Oxidation and Precipitation of Aqueous Mn(II) at the Goethite Surface: A SPM Study

Microscopy and Microanalysis ◽

10.1017/s1431927600023126 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 600-601

Author(s):

John Rakovan ◽

F. Hochella Michael

Keyword(s):

Lateral Force ◽

Atomic Scale ◽

Scanning Tunneling ◽

Mineral Surfaces ◽

Tunneling Microscopy ◽

Heterogeneous Oxidation ◽

Force Microscopy ◽

Solution Interface ◽

Atomic Force

Since its invention inl982 scanning probe microscopy (SPM) has become an important analytical tool in every branch of physical science. The two most widely used types of SPM are atomic force Microscopy (AFM) and scanning tunneling microscopy (STM). Both AFM and STM allow measurement of the microtopography of a surface down to the atomic scale. Many spin-off applications such as lateral force and magnetic force allow measurement of a variety of the physical properties of a surface while imaging its microtopography. SPM can be done in both air and liquid and hence can be used to observe the interactions that take place at a solid-solution interface.SPM has been used in mineralogy and geochemistry since 1989. Here as in other applications the great strength of SPM is in the characterization of the heterogeneous nature of mineral surfaces and the ability to observe many geochemical processes in real time.

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Atomic Resolution with the Atomic Force Microscope

Microscopy Today ◽

10.1017/s1551929500063513 ◽

1995 ◽

Vol 3 (4) ◽

pp. 6-7

Author(s):

Stephen W. Carmichael

Keyword(s):

Atomic Force Microscopy ◽

Scanning Tunneling Microscopy ◽

Atomic Force Microscope ◽

Electron transfer between anatase TiO2 and an O2 molecule directly observed by atomic force microscopy

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1618723114 ◽

2017 ◽

Vol 114 (13) ◽

pp. E2556-E2562 ◽

Cited By ~ 52

Author(s):

Martin Setvin ◽

Jan Hulva ◽

Gareth S. Parkinson ◽

Michael Schmid ◽

Ulrike Diebold

Keyword(s):

Atomic Force Microscopy ◽

Electron Transfer ◽

Photoelectron Spectroscopy ◽

Uv Light ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Near Surface ◽

Force Microscopy ◽

Atomic Force

Activation of molecular oxygen is a key step in converting fuels into energy, but there is precious little experimental insight into how the process proceeds at the atomic scale. Here, we show that a combined atomic force microscopy/scanning tunneling microscopy (AFM/STM) experiment can both distinguish neutral O2 molecules in the triplet state from negatively charged (O2)− radicals and charge and discharge the molecules at will. By measuring the chemical forces above the different species adsorbed on an anatase TiO2 surface, we show that the tip-generated (O2)− radicals are identical to those created when (i) an O2 molecule accepts an electron from a near-surface dopant or (ii) when a photo-generated electron is transferred following irradiation of the anatase sample with UV light. Kelvin probe spectroscopy measurements indicate that electron transfer between the TiO2 and the adsorbed molecules is governed by competition between electron affinity of the physisorbed (triplet) O2 and band bending induced by the (O2)− radicals. Temperature–programmed desorption and X-ray photoelectron spectroscopy data provide information about thermal stability of the species, and confirm the chemical identification inferred from AFM/STM.

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Study on the Microstructure and Electrical Properties of Boron and Sulfur Codoped Diamond Films Deposited Using Chemical Vapor Deposition

Journal of Nanomaterials ◽

10.1155/2014/109869 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7

Author(s):

Zhang Jing ◽

Li Rongbin ◽

Wang Xianghu ◽

Wei Xicheng

Keyword(s):

Grain Boundaries ◽

Measurement Techniques ◽

Diamond Films ◽

Chemical Vapor ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Force Microscopy ◽

Si Substrates ◽

Average Size

The atomic-scale microstructure and electron emission properties of boron and sulfur (denoted as B-S) codoped diamond films grown on high-temperature and high-pressure (HTHP) diamond and Si substrates were investigated using atom force microscopy (AFM), scanning tunneling microscopy (STM), secondary ion mass spectroscopy (SIMS), and current imaging tunneling spectroscopy (CITS) measurement techniques. The films grown on Si consisted of large grains with secondary nucleation, whereas those on HTHP diamond are composed of well-developed polycrystalline facets with an average size of 10–50 nm. SIMS analyses confirmed that sulfur was successfully introduced into diamond films, and a small amount of boron facilitated sulfur incorporation into diamond. Large tunneling currents were observed at some grain boundaries, and the emission character was better at the grain boundaries than that at the center of the crystal. The films grown on HTHP diamond substrates were much more perfect with higher quality than the films deposited on Si substrates. The localI-Vcharacteristics for films deposited on Si or HTHP diamond substrates indicate n-type conduction.

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Atomic-Scale Spin-Polarized Scanning Tunneling Microscopy and Atomic Force Microscopy: A Review

Journal of Scanning Probe Microscopy ◽

10.1166/jspm.2006.003 ◽

2006 ◽

Vol 1 (1) ◽

pp. 3-20 ◽

Cited By ~ 9

Author(s):

Arthur R. Smith

Keyword(s):

Atomic Force Microscopy ◽

Scanning Tunneling Microscopy ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Force Microscopy ◽

Atomic Force ◽

Spin Polarized

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Investigation of CVD graphene as-grown on Cu foil using simultaneous scanning tunneling/atomic force microscopy

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.274 ◽

2018 ◽

Vol 9 ◽

pp. 2953-2959 ◽

Cited By ~ 2

Author(s):

Majid Fazeli Jadidi ◽

Umut Kamber ◽

Oğuzhan Gürlü ◽

H Özgür Özer

Keyword(s):

Atomic Force Microscopy ◽

Carbon Atom ◽

Atomic Scale ◽

Scanning Tunneling ◽

Multilayer Graphene ◽

Hollow Site ◽

Tunneling Microscopy ◽

Force Microscopy ◽

Atomic Force ◽

Honeycomb Pattern

Scanning tunneling microscopy (STM) and atomic force microscopy (AFM) images of graphene reveal either a triangular or honeycomb pattern at the atomic scale depending on the imaging parameters. The triangular patterns at the atomic scale are particularly difficult to interpret, as the maxima in the images could be every other carbon atom in the six-fold hexagonal array or even a hollow site. Carbon sites exhibit an inequivalent electronic structure in HOPG or multilayer graphene due to the presence of a carbon atom or a hollow site underneath. In this work, we report small-amplitude, simultaneous STM/AFM imaging using a metallic (tungsten) tip, of the graphene surface as-grown by chemical vapor deposition (CVD) on Cu foils. Truly simultaneous operation is possible only with the use of small oscillation amplitudes. Under a typical STM imaging regime the force interaction is found to be repulsive. Force–distance spectroscopy revealed a maximum attractive force of about 7 nN between the tip and carbon/hollow sites. We obtained different contrast between force and STM topography images for atomic features. A honeycomb pattern showing all six carbon atoms is revealed in AFM images. In one contrast type, simultaneously acquired STM topography revealed hollow sites to be brighter. In another, a triangular array with maxima located in between the two carbon atoms was acquired in STM topography.

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Scanning Probe Microscopy of Thin Films

MRS Bulletin ◽

10.1557/s088376940004344x ◽

1993 ◽

Vol 18 (1) ◽

pp. 41-49 ◽

Cited By ~ 44

Author(s):

Steven M. Hues ◽

Richard J. Colton ◽

Ernst Meyer ◽

Hans-Joachim Güntherodt

Keyword(s):

Imaging Techniques ◽

Ambient Pressure ◽

Surface Force ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Probe Microscopy ◽

Force Microscopy ◽

Cryogenic Liquids ◽

Frictional Forces

Atomic force microscopy (AFM) was invented in 1986 by Binnig, Quate, and Gerber as “a new type of microscope capable of investigating surfaces of insulators on an atomic scale.” Stemming from developments in scanning tunneling microscopy (STM), it became possible to image insulators, organic and biological molecules, salts, glasses, and metal oxides — some under a variety of conditions, e.g., ambient pressure, in aqueous or cryogenic liquids, etc. In 1987, Mate and co-workers introduced a new application for AFM where atomic-scale frictional forces could be measured. Likewise, in 1989, Burnham and Colton used the AFM to measure the surface forces and nano-mechanical properties of materials. Today, there are many examples of using AFM as a high-resolution profilometer, surface force probe, and nanoindentor. Several new imaging techniques have been introduced; each depending on the type of force measured, e.g., magnetic, electrostatic, and capacitative. Because of the diverse nature of the field and instrumentation, the names “scanned probe microscopy” and “XFM” (where X stands for the force being measured, e.g., MFM is magnetic force microscopy) have been adopted.

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High-Resolution Imaging with Atomic Force Microscopy

Microscopy Today ◽

10.1017/s1551929500056248 ◽

2004 ◽

Vol 12 (5) ◽

pp. 12-15

Author(s):

Sergei Magonov

Keyword(s):

Atomic Force Microscopy ◽

High Resolution ◽

Atomic Scale ◽

Scanning Tunneling ◽

High Resolution Imaging ◽

Tunneling Microscopy ◽

Detection Scheme ◽

Force Microscopy ◽

Atomic Force ◽

Resolution Imaging

The invention of scanning tunneling microscopy (STM) in 1982 revolutionized surface analysis by providing atomic-scale surface imaging of conducting and semiconducting materials. Shortly after that, atomic force microscopy (AFM) was introduced as an accessory of STM for high-resolution imaging of surfaces independent of their conductivity. Mechanical force interactions between a sharp tip placed at one end of a micro fabricated cantilever and a sample surface were employed for imaging in this method. In the past decade, AFM has developed into a leading scanning probe technique applied in many fields of fundamental and industrial research. The progress of AFM has been made possible by implementation of an optical level detection scheme, which allows precise measuring of the cantilever deflection caused by the tip-sample forces, by mass microfabrication of probes consisting of cantilevers, and by developments of oscillatory imaging modes, particularly, Tapping ModeTM.

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Resolution in the scanning tunneling microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008674x ◽

1991 ◽

Vol 49 ◽

pp. 488-489

Author(s):

R. J. Wilson ◽

D. D. Chambliss ◽

S. Chiang ◽

V. M. Hallmark

Keyword(s):

Scanning Tunneling Microscope ◽

Fundamental Principle ◽

Atomic Scale ◽

Lateral Resolution ◽

Scanning Tunneling ◽

Electronic Noise ◽

Vertical Resolution ◽

Tunneling Microscopy ◽

Spatial Profile ◽

Theoretical Analyses

Scanning tunneling microscopy (STM) has been used for many atomic scale observations of metal and semiconductor surfaces. The fundamental principle of the microscope involves the tunneling of evanescent electrons through a 10Å gap between a sharp tip and a reasonably conductive sample at energies in the eV range. Lateral and vertical resolution are used to define the minimum detectable width and height of observed features. Theoretical analyses first discussed lateral resolution in idealized cases, and recent work includes more general considerations. In all cases it is concluded that lateral resolution in STM depends upon the spatial profile of electronic states of both the sample and tip at energies near the Fermi level. Vertical resolution is typically limited by mechanical and electronic noise.

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Scanning tunneling microscopy and atomic force microscopy: New tools for biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155864 ◽

1989 ◽

Vol 47 ◽

pp. 778-779

Author(s):

CE Bracker ◽

P. K. Hansma

Keyword(s):

Physical Property ◽

Scanning Probe ◽

Scanning Tunneling ◽

Small Scale ◽

Tunneling Microscopy ◽

Force Microscopy ◽

New Family ◽

Small Probe ◽

Atomic Force ◽

Transmission Electron

A new family of scanning probe microscopes has emerged that is opening new horizons for investigating the fine structure of matter. The earliest and best known of these instruments is the scanning tunneling microscope (STM). First published in 1982, the STM earned the 1986 Nobel Prize in Physics for two of its inventors, G. Binnig and H. Rohrer. They shared the prize with E. Ruska for his work that had led to the development of the transmission electron microscope half a century earlier. It seems appropriate that the award embodied this particular blend of the old and the new because it demonstrated to the world a long overdue respect for the enormous contributions electron microscopy has made to the understanding of matter, and at the same time it signalled the dawn of a new age in microscopy. What we are seeing is a revolution in microscopy and a redefinition of the concept of a microscope.Several kinds of scanning probe microscopes now exist, and the number is increasing. What they share in common is a small probe that is scanned over the surface of a specimen and measures a physical property on a very small scale, at or near the surface. Scanning probes can measure temperature, magnetic fields, tunneling currents, voltage, force, and ion currents, among others.

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