Effects of arsenic concentration on the formation of dislocation loops near the projected ion range in high‐dose As+‐implanted (001) Si

1989 ◽  
Vol 55 (22) ◽  
pp. 2304-2306 ◽  
Author(s):  
S. N. Hsu ◽  
L. J. Chen
Keyword(s):  
Arsenic Concentration ◽  
High Dose ◽  
Dislocation Loops

Study of dislocation loops in Arsenic-Rich as-grown GaAs

1987 ◽  
Vol 45 ◽  
pp. 350-351
Author(s):  
Byung-Teak Lee
Keyword(s):  
Point Defects ◽  
Electronic Devices ◽  
Arsenic Concentration ◽  
Stoichiometric Compound ◽  
Dislocation Loops ◽  
Gaas Crystal ◽  
Ion Milling ◽  
Transmission Electron ◽  
Arsenic Source ◽  
High Arsenic

Grown-in dislocations in GaAs have been a major obstacle in utilizing this material for the potential electronic devices. Although it has been proposed in many reports that supersaturation of point defects can generate dislocation loops in growing crystals and can be a main formation mechanism of grown-in dislocations, there are very few reports on either the observation or the structural analysis of the stoichiometry-generated loops. In this work, dislocation loops in an arsenic-rich GaAs crystal have been studied by transmission electron microscopy.The single crystal with high arsenic concentration was grown using the Horizontal Bridgman method. The arsenic source temperature during the crystal growth was about 630°C whereas 617±1°C is normally believed to be optimum one to grow a stoichiometric compound. Samples with various orientations were prepared either by chemical thinning or ion milling and examined in both a JEOL JEM 200CX and a Siemens Elmiskop 102.

An Investigation Of Vacancy Population During Arsenic Activation In Silicon

1996 ◽  
Vol 442 ◽  
Author(s):  
O. Dokumaci ◽  
H.-J. Gossmann ◽  
K. S. Jones ◽  
M. E. Law
Keyword(s):  
Arsenic Concentration ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Experimental Investigations ◽  
Excess Vacancy ◽  
Activation Process ◽  
Dislocation Loops ◽  
Plan View ◽  
Sb Doping ◽  
Superlattice Structures

AbstractRecent experimental investigations have shown that electrical deactivation of arsenic in silicon creates excess silicon interstitials. This study investigated the possibility of excess vacancy generation during arsenic activation. We used Sb doping superlattice structures containing six 10 nm wide Sb doped spikes separated by 100 nm. It was found that antimony diffusion was not enhanced as active arsenic concentration increased, indicating there is no observable vacancy injection out of the arsenic layer during the activation process. Plan-view transmission electron microscopy study of the samples revealed dislocation loops before the activation anneal. Although the loops completely dissolved during the activation anneal, they do not seem to be sufficient enough to absorb all the vacancies generated by the activated arsenic. When germanium was present at the surface instead of arsenic, antimony diffusion was enhanced.

Ion Beam Induced Intermixing of Wsi0.45 on GaAs

1988 ◽  
Vol 128 ◽  
Author(s):  
S. J. Pearton ◽  
K. T. Short ◽  
K. S. Jones ◽  
A. G. Baca ◽  
C. S. Wu
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Ion Beam ◽  
Dose Range ◽  
Device Fabrication ◽  
Electrical Activation ◽  
High Dose ◽  
Dislocation Loops ◽  
Semiconductor Interface ◽  
High Level

ABSTRACTThe systematics of ion beam induced intermixing of WSi0.45 on GaAs have been studied after through-implantation of Si or O in the dose range 1013 − 5 × 1016 cm−2. SIMS profiling shows significant knock-on of Si and W into the GaAs at the high dose range in accordance with Monte Carlo simulations, but there is virtually no electrical activation (≤0.1%) of this Si after normal implant annealing (900°C, 10 sec). This appears to be a result of the high level of disorder near the metal-semiconductor interface, which is not repaired by annealing. This damage consists primarily of dislocation loops extending a few hundred angstroms below the end of range of the implanted ions. Extrapolation of the ion doses used in this work to the usual doses used in GaAs device fabrication would imply that ion-induced intermixing of WSix will not be significant in through-implantation processes.

Defect-Characterization in Implanted Locos + Trench-Isolated Structures

1991 ◽  
Vol 239 ◽  
Author(s):  
N. David Theodore ◽  
Barbara Vasquez ◽  
Peter Fejes
Keyword(s):  
Integrated Circuits ◽  
Cross Section ◽  
High Dose ◽  
Defect Characterization ◽  
Dislocation Loops ◽  
Etch Pits ◽  
Local Oxidation ◽  
Silicon Integrated Circuits ◽  
Trench Isolation ◽  
Dislocation Sources

ABSTRACTAs device dimensions decrease in silicon integrated-circuits, conventional LOCOS (local-oxidation of silicon) isolation becomes inadequate to meet dimensional demands. Variations on LOCOS are therefore being explored for further miniaturization of devices. One such variation involves poly-buffered LOCOS + trench-isolation (PBLT). In this study, PBLT structures were characterized using TEM. Wright-etched cross-section SEM micrographs showed etch-pits associated with a combination of high-dose (> 5E14 cm-2) phosphorous implants and PBLT isolation. TEM characterization showed that dislocations were formed in the structures for a combination of high-dose (1E15 cm-2) phosphorous implants (followed by an anneal) and PBLT isolation. Structures exposed to lower-dose (1E14 cm-2) implants showed no defects and neither did 1E15 implanted structures prior to annealing. The results are modelled in terms of the stress configurations present in the structures, and in terms of dislocation-sources resulting from implantation-related dislocation-loops. The dislocation-sources operate in the presence of stresses associated with the isolation-trenches. Glide-loops form, which then grow in response to stresses in the structures and dislocations result on glide planes.

Structure Determination of Clusters Formed in Ultra-Low Energy High-Dose Implanted Silicon

2005 ◽  
Vol 108-109 ◽  
pp. 303-308 ◽  
Author(s):  
N. Cherkashin ◽  
Martin J. Hÿtch ◽  
Fuccio Cristiano ◽  
A. Claverie
Keyword(s):  
Electron Microscopy ◽  
Geometric Phase ◽  
Low Energy ◽  
High Dose ◽  
Dislocation Loops ◽  
Weak Beam ◽  
Transmission Electron ◽  
Geometric Phase Analysis

In this work, we present a detailed structural characterization of the defects formed after 0.5 keV B+ implantation into Si to a dose of 1x1015 ions/cm2 and annealed at 650°C and 750°C during different times up to 160 s. The clusters were characterized by making use of Weak Beam and High Resolution Transmission Electron Microscopy (HRTEM) imaging. They are found to be platelets of several nanometer size with (001) habit plane. Conventional TEM procedure based on defect contrast behavior was applied to determine the directions of their Burger’s vectors. Geometric Phase Analysis of HRTEM images was used to measure the displacement field around these objects and, thus, to unambiguously determine their Burger’s vectors. Finally five types of dislocation loops lying on (001) plane are marked out: with ] 001 [1/3 ≅ b and b ∝ [1 0 1], [-1 0 1], [0 1 1], [0 -1 1].

On the Energetics of Extrinsic Defects in Si and their Role in Nonequilibrium Dopant Diffusion

2000 ◽  
Vol 610 ◽  
Author(s):  
Alain Claverie ◽  
Filadelfo Cristiano ◽  
Benjamin Colombeau ◽  
Nicholas Cowern
Keyword(s):  
Formation Energy ◽  
Ostwald Ripening ◽  
High Dose ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Dynamical Equilibrium ◽  
Defect Interactions ◽  
Small Clusters ◽  
Dose Levels ◽  
Extrinsic Defects

AbstractIn this paper, we discuss the mechanisms by which small clusters evolve through “magic” sizes into {113} defects and then, at sufficiently high dose levels, transform into dislocation loops of two types. This ripening process is mediated by the interchange of free Si(int)s between different extended defects, leading to a decrease of their formation energy. The calculation of the supersaturation of free Si-interstitials in dynamical equilibrium with these defects shows a hierarchy of levels of nonequilibrium diffusion, ranging from supersaturations S of about 106 in the presence of small clusters, through 103 in the presence of {113} defects, to S in the range 100 down to 1 as loops are formed, evolve and finally evaporate. A detailed analysis of defect energetics has been carried out and it is shown that Ostwald ripening is the key concept for understanding and modelling defect interactions during TED of dopants in silicon.

Damage Removal Processes in Ion Implanted, Rapidly Annealed GaAs

1985 ◽  
Vol 52 ◽  
Author(s):  
D. C. Jacobson ◽  
S. J. Pearton ◽  
R. Hull ◽  
J. M. Poate ◽  
J. S. Williams
Keyword(s):  
Carrier Mobility ◽  
Secondary Ion Mass Spectrometry ◽  
High Dose ◽  
Electrical Characteristics ◽  
Dislocation Loops ◽  
Transmission Electron ◽  
Capacitance Voltage ◽  
Lattice Damage ◽  
Removal Processes ◽  
Secondary Ion

ABSTRACTThe removal of lattice damage and consequent activation by rapid thermal annealing of implanted Si, Se, Zn and Be in GaAs was investigated by capacitance-voltage profiling, Hall measurements, transmission electron microscopy (TEM), secondary ion mass spectrometry and Rutherford backscattering. The lighter species show optimum electrical characteristics at lower annealing temperatures (˜850°C for Be, ˜950°C for Si) than the heavier species (˜900°C for Zn, ˜1000°C for Se), consistent with the amount of lattice damage remaining after annealing. TEM reveals the formation of high densities (107 cm−2) of dislocation loops after 800°C, 3s anneals of high dose (1×1015 cm−2) implanted GaAs, which are gradually reduced in density after higher temperatures anneals (˜1000°C). The remaining loops do not appear to effect the electrical activation or carrier mobility in the implanted layer, the latter being comparable to bulk values.

scholarly journals Association between lung cancer risk and inorganic arsenic concentration in drinking water: a dose–response meta-analysis

2018 ◽  
Vol 7 (6) ◽  
pp. 1257-1266 ◽  
Author(s):  
Tanwei Yuan ◽  
Hongbo zhang ◽  
Bin Chen ◽  
Hong Zhang ◽  
Shasha Tao
Keyword(s):  
Lung Cancer ◽  
Drinking Water ◽  
Dose Response ◽  
Lung Cancer Risk ◽  
Meta Analysis ◽  
Arsenic Concentration ◽  
Inorganic Arsenic ◽  
High Dose ◽  
Cancer Risks ◽  
Dose Response Relationship

High dose arsenic in drinking water (≥100 μg L−1) is known to induce lung cancer, but lung cancer risks at low to moderate arsenic levels and its dose–response relationship remains inconclusive.

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