Very weak bonds to artificial atoms formed by quantum corrals

We explored the bonding properties of the quantum corral (a circle of 48 iron atoms placed on a copper surface) reported by Crommie, Lutz and Eigler in 1993, along with variants, as an artificial atom using an atomic force microscope (AFM). The original corral geometry confines 102 electrons to 28 discrete energy states, and we find that these states can form a bond to the front atom of the AFM with an energy of about 5 millielectron volts. The measured forces are about 1/1000 of typical forces in atomically resolved AFM. The confined electrons showed covalent attraction to metal tips and Pauli repulsion to CO-terminated tips. The repulsion at close distance was evident from the response of corral states created by deliberately placing single iron atoms inside the corral. The forces scaled appropriately with a 24-atom corral.

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Characterization of photosystem II with the atomic-force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130365 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1146-1147

Author(s):

Kathleen M. Marr ◽

Mary K. Lyon

Keyword(s):

Photosystem Ii ◽

Atomic Force Microscope ◽

Three Dimensional ◽

Biologically Active ◽

Atomic Force ◽

Freeze Etching ◽

Image Averaging ◽

Oxygen Evolving ◽

Averaging Techniques

Photosystem II (PSII) is different from all other reaction centers in that it splits water to evolve oxygen and hydrogen ions. This unique ability to evolve oxygen is partly due to three oxygen evolving polypeptides (OEPs) associated with the PSII complex. Freeze etching on grana derived insideout membranes revealed that the OEPs contribute to the observed tetrameric nature of the PSIl particle; when the OEPs are removed, a distinct dimer emerges. Thus, the surface of the PSII complex changes dramatically upon removal of these polypeptides. The atomic force microscope (AFM) is ideal for examining surface topography. The instrument provides a topographical view of individual PSII complexes, giving relatively high resolution three-dimensional information without image averaging techniques. In addition, the use of a fluid cell allows a biologically active sample to be maintained under fully hydrated and physiologically buffered conditions. The OEPs associated with PSII may be sequentially removed, thereby changing the surface of the complex by one polypeptide at a time.

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Imaging polymers, proteins and dna in aqueous solutions with the atomic force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152136 ◽

1989 ◽

Vol 47 ◽

pp. 32-33

Author(s):

S.A.C. Gould ◽

B. Drake ◽

C.B. Prater ◽

A.L. Weisenhorn ◽

S.M. Lindsay ◽

...

Keyword(s):

Amino Acids ◽

Dna Sequencing ◽

Aqueous Solutions ◽

Atomic Force Microscope ◽

Piezoelectric Crystal ◽

Atomic Force ◽

Structure Of Molecules ◽

Optical Lever

The atomic force microscope (AFM) is an instrument that can be used to image many samples of interest in biology and medicine. Images of polymerized amino acids, polyalanine and polyphenylalanine demonstrate the potential of the AFM for revealing the structure of molecules. Images of the protein fibrinogen which agree with TEM images demonstrate that the AFM can provide topographical data on larger molecules. Finally, images of DNA suggest the AFM may soon provide an easier and faster technique for DNA sequencing.The AFM consists of a microfabricated SiO2 triangular shaped cantilever with a diamond tip affixed at the elbow to act as a probe. The sample is mounted on a electronically driven piezoelectric crystal. It is then placed in contact with the tip and scanned. The topography of the surface causes minute deflections in the 100 μm long cantilever which are detected using an optical lever.

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The atomic-force microscope and its future in biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149350 ◽

1993 ◽

Vol 51 ◽

pp. 704-705

Author(s):

Jean-Paul Revel

Keyword(s):

Silicon Nitride ◽

Laser Beam ◽

Atomic Force Microscope ◽

Scanning Tunneling Microscope ◽

Point Of View ◽

Scanning Tunneling ◽

Close Relative ◽

Tunneling Microscope ◽

Atomic Force ◽

Sharp Point

The last few years have been marked by a series of remarkable developments in microscopy. Perhaps the most amazing of these is the growth of microscopies which use devices where the place of the lens has been taken by probes, which record information about the sample and display it in a spatial from the point of view of the context. From the point of view of the biologist one of the most promising of these microscopies without lenses is the scanned force microscope, aka atomic force microscope.This instrument was invented by Binnig, Quate and Gerber and is a close relative of the scanning tunneling microscope. Today's AFMs consist of a cantilever which bears a sharp point at its end. Often this is a silicon nitride pyramid, but there are many variations, the object of which is to make the tip sharper. A laser beam is directed at the back of the cantilever and is reflected into a split, or quadrant photodiode.

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Electrostatic displacement of multiwalled carbon nanotubes by scanning a voltage-applied tip of an atomic force microscope

The European Physical Journal Applied Physics ◽

10.1051/epjap:2004199 ◽

2004 ◽

Vol 28 (3) ◽

pp. 301-304 ◽

Cited By ~ 3

Author(s):

D.-H. Kim ◽

J.-Y. Koo ◽

J.-J. Kim

Keyword(s):

Carbon Nanotubes ◽

Atomic Force Microscope ◽

Multiwalled Carbon Nanotubes ◽

Multiwalled Carbon ◽

Atomic Force

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The application of atomic force microscope in microbiological research

Forum Zakażeń ◽

10.15374/fz2014008 ◽

2014 ◽

Vol 5 (1) ◽

pp. 27-30

Author(s):

Małgorzata Tokarska-Rodak ◽

Maria Kozioł-Montewka ◽

Jolanta Paluch-Oleś ◽

Dorota Plewik ◽

Grażyna Olchowik ◽

...

Keyword(s):

Atomic Force Microscope ◽

Atomic Force ◽

Microbiological Research

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A NEW MODEL FOR CONTACT INTERACTION BETWEEN AN ATOMIC FORCE MICROSCOPE PROBE AND A SAMPLE

Nanomechanics Science and Technology An International Journal ◽

10.1615/nanomechanicsscitechnolintj.v6.i3.10 ◽

2015 ◽

Vol 6 (3) ◽

pp. 179-191

Author(s):

N. I. Uzhegova ◽

A. L. Svistkov

Keyword(s):

Atomic Force Microscope ◽

Contact Interaction ◽

Atomic Force Microscope Probe ◽

New Model ◽

Atomic Force ◽

Microscope Probe

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Failure Analysis of Laser Blown Metal Fuse Failures in Submicron Technology by C-AFM

ISTFA 2006: Conference Proceedings from the 32nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2006p0260 ◽

2006 ◽

Author(s):

Liang-Feng Wen ◽

Chien-Hui Chen ◽

Allen Timothy Chang

Keyword(s):

Failure Analysis ◽

Atomic Force Microscope ◽

Laser Cutting ◽

Spot Size ◽

Repair Rate ◽

Atomic Force ◽

Measurement Laser

Abstract This paper presents a method of using a conductive atomic force microscope (C-AFM) to characterize a submicron metal fuse that has been blown open inadequately by laser. In order to obtain a proper I-V curve measured using the C-AFM without affecting the incompletely opened fuse, the paper proposes a method of preserving the fuse by coating its surface with spin-on glass. The paper explains how differences in laser cutting machines resulted in the high failure repair rate of customer product despite equivalent energy and spot size settings. Analysis of the fuse bank circuitry on wafers helped to find the critical physical differences between a fully blown and a poorly blown fuse. By overcoming difficulties in preserving the blown fuse failure sites for C-AFM measurement, laser settings could be easily optimized to ensure proper fuse opening.

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A Study of the Photoelectric Effect Caused by a Laser Beam Used in a Beam Bounce Technique in a C-AFM System

ISTFA 2008: Conference Proceedings from the 34th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2008p0256 ◽

2008 ◽

Author(s):

Hung-Sung Lin ◽

Mong-Sheng Wu

Keyword(s):

Laser Beam ◽

Failure Analysis ◽

Atomic Force Microscope ◽

Photoelectric Effect ◽

Scanning Probe ◽

Nanometer Scale ◽

Electrical Characteristics ◽

Atomic Force ◽

Probe Microscope ◽

Probe Head

Abstract The use of a scanning probe microscope (SPM), such as a conductive atomic force microscope (C-AFM) has been widely reported as a method of failure analysis in nanometer scale science and technology [1-6]. A beam bounce technique is usually used to enable the probe head to measure extremely small movements of the cantilever as it is moved across the surface of the sample. However, the laser beam used for a beam bounce also gives rise to the photoelectric effect while we are measuring the electrical characteristics of a device, such as a pn junction. In this paper, the photocurrent for a device caused by photon illumination was quantitatively evaluated. In addition, this paper also presents an example of an application of the C-AFM as a tool for the failure analysis of trap defects by taking advantage of the photoelectric effect.

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