Twin defect-triggered deformations and Bi segregation in GaAs/GaAsBi core–multishell nanowires

ABSTRACTWhile many studies have been made of liquid phase epitaxy impurity trapping and segregation in Si little is known about the equivalent processes in Ge. In this paper we have laser annealed Ge <100> and <111> crystals implanted, at liquid nitrogen temperature, with 200 keV 210Bi ions to doses of 2 × 1015 and 1016 ions cm−2. The samples were annealed with Q-switched ruby lasers and an XeCl excimer laser. We have observed 1) velocity and orientation dependence of the Bi segregation coefficient 2) interface instability and cell formation resulting from constitutional supercooling and 3) amorphization and defect production at high velocities. The phenomena are shown to be analogous to those seen in Si.

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Improving tensile and fatigue properties of Sn–58Bi/Cu solder joints through alloying substrate

Journal of Materials Research ◽

10.1557/jmr.2010.0035 ◽

2010 ◽

Vol 25 (2) ◽

pp. 303-314 ◽

Cited By ~ 33

Author(s):

QingKe Zhang ◽

HeFei Zou ◽

Zhe-Feng Zhang

Keyword(s):

Fatigue Life ◽

Tensile Property ◽

Adhesive Strength ◽

Solder Joints ◽

Fatigue Properties ◽

Fracture Mechanisms ◽

Cu Substrate ◽

Fatigue And Fracture ◽

Long Time ◽

Bi Segregation

To eliminate the Bi segregation and interfacial embrittlement of the SnBi/Cu joints, we deliberately added some Ag or Zn elements into the Cu substrate. Then, the reliability of the SnBi/Cu–X (X = Ag or Zn) solder joints was evaluated by investigating their interfacial reactions, tensile property, and fatigue life compared with those of the SnBi/Cu and SnAg/Cu joints. The experimental results demonstrate that even after aging for a long time, the addition of the Ag or Zn elements into the Cu substrate can effectively eliminate the interfacial Bi embrittlement of the SnBi/Cu–X joints under tensile or fatigue loadings. Compared with the conventional SnAg/Cu joints, the SnBi/Cu–X joints exhibit higher adhesive strength and comparable fatigue resistance. Finally, the fatigue and fracture mechanisms of the SnBi/Cu–X solder joints were discussed qualitatively. The current findings may pave the new way for the Sn–Bi solder widely used in the electronic interconnection in the future.

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Auger Electron Spectroscopical Investigation of Interfacial Segregation in the Cu-Bi System

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.237-240.1141 ◽

2005 ◽

Vol 237-240 ◽

pp. 1141-1146

Author(s):

Gabriel A. López ◽

Eric J. Mittemeijer

Keyword(s):

Grain Boundary ◽

Auger Electron ◽

Surface Segregation ◽

Vacuum Chamber ◽

Systematic Investigation ◽

Special Method ◽

Free Surfaces ◽

Internal Cavities ◽

Bi Segregation ◽

First Time

A systematic investigation of the segregation of Bi at both free surfaces and grain boundaries in Cu, under identical conditions, is reported. The problem of Bi evaporation upon Bi segregation at free surfaces was overcome using a special method for sample preparation. Cu bicrystals containing deliberately made internal cavities at the grain boundary were doped with Bi, annealed at temperatures between 1073 and 1223 K, and broken along the grain boundary in an ultrahigh vacuum chamber for Auger electron spectroscopy. For the first time, the equilibrium surface segregation of Bi in Cu has been measured. The segregation at the free surface was found to be stronger than the segregation at the grain boundary.

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Twin defect modes in one-dimensional photonic crystals with a single-negative material defect

Applied Physics Letters ◽

10.1063/1.2357600 ◽

2006 ◽

Vol 89 (14) ◽

pp. 141101 ◽

Cited By ~ 32

Author(s):

Y. H. Chen ◽

J. W. Dong ◽

H. Z. Wang

Keyword(s):

Photonic Crystals ◽

Defect Modes ◽

One Dimensional ◽

Twin Defect ◽

Negative Material

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Quantitative Determination of Bi Segregation at Grain Boundaries in Cu Bicrystals

Microscopy and Microanalysis ◽

10.1017/s1431927600009569 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 535-536

Author(s):

U. Alber ◽

H. Müllejans ◽

M. Rühle

Keyword(s):

Electron Beam ◽

Grain Boundaries ◽

Primary Electron ◽

Atomic Scale ◽

Beam Diameter ◽

Primary Electron Beam ◽

Impurity Segregation ◽

A Value ◽

Bi Segregation ◽

Beam Broadening

Impurity segregation at grain boundaries (GB) can be detected by EDS in a dedicated STEM. Quantification of the segregation requires not only quantification of the spectra but also consideration of the geometry of the experiment. Our aim was to obtain a value which characterises only the segregation of the impurity and is independent of experimental parameters. The problem is that the specimen composition at the GB is extremely inhomogeneous on an atomic scale in the case of Bi segregation at GBs in Cu. The analysed volume which is defined by the irradiated area and the beam broadening of the primary electron beam inside the specimen contains the interfacial plane as well as neighbouring bulk Cu. One approach is to put the focussed primary electron beam on the interface which is aligned edge on and acquire a spectrum. Both the primary beam diameter and the beam broadening inside the specimen have to be known.

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N-Channel Sub-Threshold Leakage “Pipes” Generated From Micro-Twinning Near Shallow Trench Isolation Interface

ISTFA 2002: Conference Proceedings from the 28th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2002p0599 ◽

2002 ◽

Author(s):

Erick M. Spory

Keyword(s):

Compressive Stress ◽

Process Parameters ◽

Shallow Trench Isolation ◽

Silicon Lattice ◽

Corner Region ◽

Twin Defect ◽

Close Proximity ◽

Trench Isolation ◽

Pipe Formation ◽

Very High

Abstract The pursuit of shorter and narrower channel transistor processes, especially those employing Shallow Trench Isolation (STI), can readily produce devices that are increasingly susceptible to the formation of sub-threshold, leakage-generating defects. Specifically, STI N-channel devices exhibiting lengths at or below 0.35 um and with widths below 1 um, are at a heightened risk of developing a channel micro-twin defect “pipe” due to the very high compressive stress within the silicon lattice. Wider, sub-0.35 um devices can also exhibit the problem if their channels are in extremely close proximity to an active/STI corner region. Modification of the relevant process parameters can significantly alleviate this stress and reduce the frequency of “pipe” formation.

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