Theoretical analysis of magnetically switched transparency in planar semiconductor interfaces

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

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An atomic-resolution microscope study of Al contracts on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145005 ◽

1986 ◽

Vol 44 ◽

pp. 726-727

Author(s):

Z. Liliental-Weber ◽

C. Nelson ◽

R. Ludeke ◽

R. Gronsky ◽

J. Washburn

Keyword(s):

High Speed ◽

Schottky Contacts ◽

Detailed Knowledge ◽

The Past ◽

Semiconductor Interfaces ◽

Deposited Metal ◽

Microwave Applications ◽

Free Interfaces ◽

Potential Use

The properties of metal/semiconductor interfaces have received considerable attention over the past few years, and the Al/GaAs system is of special interest because of its potential use in high-speed logic integrated optics, and microwave applications. For such materials a detailed knowledge of the geometric and electronic structure of the interface is fundamental to an understanding of the electrical properties of the contact. It is well known that the properties of Schottky contacts are established within a few atomic layers of the deposited metal. Therefore surface contamination can play a significant role. A method for fabricating contamination-free interfaces is absolutely necessary for reproducible properties, and molecularbeam epitaxy (MBE) offers such advantages for in-situ metal deposition under UHV conditions

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High-resolution z-contrast imaging of semiconductor interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154317 ◽

1989 ◽

Vol 47 ◽

pp. 468-469

Author(s):

S. J. Pennycook

Keyword(s):

High Resolution ◽

Phase Contrast ◽

Contrast Imaging ◽

Compositional Modulation ◽

Semiconductor Interfaces ◽

Complex Figure ◽

Thin Region ◽

Stem Image ◽

Annular Detector ◽

Z Contrast

Using a high-angle annular detector on a high-resolution STEM it is possible to form incoherent images of a crystal lattice characterized by strong atomic number or Z contrast. Figure 1 shows an epitaxial Ge film on Si(100) grown by oxidation of Ge-implanted Si. The image was obtained using a VG Microscopes' HB501 STEM equipped with an ultrahigh resolution polepiece (Cs ∽1.2 mm, demonstrated probe FWHM intensity ∽0.22 nm). In both crystals the lattice is resolved but that of Ge shows much brighter allowing the interface to be located exactly and interface steps to be resolved (arrowed). The interface was indistinguishable in the phase-contrast STEM image from the same region, and even at higher resolution the location of the interface is complex. Figure 2 shows a thin region of an MBE-grown ultrathin super-lattice (Si8Ge2)100. The expected compositional modulation would show as one bright row of dots from the 2 Ge monolayers separated by 4 rows of lighter Si columns. The image shows clearly that strain-induced interdiffusion has occurred on the monolayer scale.

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Theoretical analysis of a monopole antenna with conducting flat disk above the earth

Electronics and Communications in Japan (Part I Communications) ◽

10.1002/ecja.1021.abs ◽

2001 ◽

Vol 84 (7) ◽

pp. 27-36

Author(s):

Aki Yuasa ◽

Daisuke Itatsu ◽

Naoki Inagaki ◽

Nobuyoshi Kikuma

Keyword(s):

Theoretical Analysis ◽

Monopole Antenna ◽

The Earth ◽

Flat Disk

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Context Aversion, Pavlovian Conditioning, and the Psychological Side Effects of Chemotherapy

European Psychologist ◽

10.1027/1016-9040.2.118 ◽

1997 ◽

Vol 2 (2) ◽

pp. 118-124

Author(s):

Geoffrey Hall

Keyword(s):

Animal Model ◽

Side Effects ◽

Theoretical Analysis ◽

Conditioned Response ◽

Behavioral Strategies ◽

Contextual Cues ◽

Anticipatory Nausea ◽

Laboratory Rats ◽

Anticipatory Nausea And Vomiting ◽

Parallel Case

Patients who have undergone several sessions of chemotherapy for cancer will sometimes develop anticipatory nausea and vomiting (ANV), these unpleasant side effects occurring as the patients return to the clinic for a further session of treatment. Pavlov's analysis of learning allows that previously neutral cues, such as those that characterize a given place or context, can become associated with events that occur in that context. ANV could thus constitute an example of a conditioned response elicited by the contextual cues of the clinic. In order to investigate this proposal we have begun an experimental analysis of a parallel case in which laboratory rats are given a nausea-inducing treatment in a novel context. We have developed a robust procedure for assessing the acquisition of context aversion in rats given such training, a procedure that shows promise as a possible animal model of ANV. Theoretical analysis of the conditioning processes involved in the formation of context aversions in animals suggests possible behavioral strategies that might be used in the alleviation of ANV, and we report a preliminary experimental test of one of these.

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