Point Defects in Materials Part II: Applications to Different Materials Problems

MRS Bulletin ◽  
1991 ◽  
Vol 16 (12) ◽  
pp. 18-21
Author(s):  
David Seidman ◽  
Donglu Shi
Keyword(s):  
Metal Oxides ◽  
Point Defect ◽  
Intermetallic Compounds ◽  
Point Defects ◽  
Electronic Materials ◽  
Material Behavior ◽  
Type Ii ◽  
Defect Engineering ◽  
Type Ii Superconductors ◽  
Wide Range

This issue of the MRS Bulletin follows up on the November issue's five articles on point defect phenomena in a wide range of materials with five more articles on point defects. The present articles emphasize the behavior of different phenomena in various materials—nonstoichiometric metal oxides, intermetallic compounds, type II superconductors and semiconductors—in terms of fundamental properties of point defects. Again, point defects is the unifying theme but the emphasis shifts to material behavior.This issue begins with Marshall Stoneham's article on the roles theory plays in predicting and understanding material behavior in terms of point defects in the different classes of materials. The following article by Rüdiger Dieckmann discusses the relationships between point defect concentrations in nonstoichiometric metal oxides and diffusion, i.e., mass transport. Next, Georges Martin and Pascal Bellon review their new approach for analyzing the role played by antisite defects in nonequilibrium phase transitions in intermetallic compounds. Then, Donglu Shi focuses on the effect of point, line, and planar defects on three major properties of type II superconductors—the critical transition temperature, the upper critical magnetic field, and the critical current density. Finally, Lionel Kimerling shows how defect engineering is used to achieve a high degree of complexity in product fabrication and greater sophistication in product performance; he illustrates what he means by defect engineering with examples from basic processes used in electronic materials processing.

Application of High Energy Ion Beam on the Control of Boron Diffusion

2003 ◽  
Vol 792 ◽  
Author(s):  
Wei-Kan Chu ◽  
Lin Shao ◽  
Jiarui Liu
Keyword(s):  
Point Defect ◽  
Point Defects ◽  
Anomalous Diffusion ◽  
Ion Beam ◽  
Surface Region ◽  
High Energy ◽  
Boron Diffusion ◽  
Defect Engineering ◽  
Projected Range ◽  
Ultrashallow Junction

ABSTRACTAnomalous diffusion of boron during annealing is a detriment on the fabrication of ultrashallow junction required by the next generation Si devices. This has driven the need to develop new doping methods. In the point defect engineering approach, high-energy ion bombardments inject vacancies near the surface region and create excessive interstitials near the end of projected range of incident ions. Such manipulation of point defects can retard boron diffusion and enhance activation of boron. We will review the current understanding of boron diffusion and our recent activities in point defect engineering.

Point Defect Detector Studies of Ge+ Implanted Silicon upon Oxidation

1992 ◽  
Vol 262 ◽  
Author(s):  
H. L. Meng ◽  
S. Prusstn ◽  
K. S. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Point Defect ◽  
Point Defects ◽  
Type Ii ◽  
Dislocation Loops ◽  
Furnace Annealing ◽  
Plan View ◽  
Atom Concentration ◽  
Transmission Electron

ABSTRACTPrevious results [1] have shown that type II (end-of-range) dislocation loops can be used as point defect detectors and are efficient in measuring oxidation induced point defects. This study investigates the interaction between oxidation-induced point defects and dislocation loops when Ge+ implantation was used to form the type II dislocation loops. The type II dislocation loops were introduced via Ge+ implants into <100> Si wafers at 100 keV to at doses ranging from 2×1015 to l×1016/cm2. The subsequent furnace annealing at 900 °C was done for times between 30 min and 4 hr in either a dry oxygen or nitrogen ambient. The change in atom concentration bound by dislocation loops as a result of oxidation was measured by plan-view transmission electron microscopy (PTEM). The results show that the oxidation rate for Ge implanted Si is similar to Si+ implanted Si. Upon oxidation a decrease in the interstitial injection was observed for the Ge implanted samples relative to the Si implanted samples. With increasing Ge+ dose the trapped atom concentration bound by the loops actually decreases upon oxidation relative to the inert ambient implying oxidation of Ge+ implanted silicon can result in either vacancy injection or the formation of an interstitial sink.

Mechanisms of the electron irradiation-induced amorphous transition in intermetallic compounds

1986 ◽  
Vol 1 (3) ◽  
pp. 425-441 ◽  
Author(s):  
D.F. Pedraza
Keyword(s):  
Point Defect ◽  
Intermetallic Compounds ◽  
Point Defects ◽  
Tini Alloy ◽  
Sink Strength ◽  
Lattice Instability ◽  
Temperature Dependent ◽  
Defect Production ◽  
Theoretical Predictions ◽  
Radiation Induced

A buildup of radiation-induced lattice defects is proposed as the cause for lattice instability that can give rise to a crystalline-to-amorphous transition. An analysis of published experiments on intermetallic compounds suggests that, when amorphization takes place, no microstructural evolution based on the aggregation of like-point defects occurs. This observation leads us to suggest that buildup of a different type of defect, which will destabilize the crystal, should occur. We thus propose that an interstitial and a vacancy may form a complex, giving rise to a relaxed configuration exhibiting a sort of short-range order. Two mechanisms of complex formation are analyzed, one diffusionless (limited by the point defect production rate) and the other temperature dependent. The amorphization kinetics as a function of temperature, dose, and point defect sink strength are studied. Theoretical predictions on the amorphization dose as a function of temperature are made for the equiatomic TiNi alloy and compared with available experimental results.

scholarly journals Structure and Superconductivity of Tin-Containing HfTiZrSnM (M = Cu, Fe, Nb, Ni) Medium-Entropy and High-Entropy Alloys

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3953
Author(s):  
Darja Gačnik ◽  
Andreja Jelen ◽  
Mitja Krnel ◽  
Stanislav Vrtnik ◽  
Jože Luzar ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Transition Metals ◽  
Physical Properties ◽  
Specific Heat ◽  
Intermetallic Compounds ◽  
High Entropy Alloys ◽  
Type Ii ◽  
High Entropy ◽  
Type Ii Superconductors ◽  
Multi Phase

In an attempt to incorporate tin (Sn) into high-entropy alloys composed of refractory metals Hf, Nb, Ti and Zr with the addition of 3d transition metals Cu, Fe, and Ni, we synthesized a series of alloys in the system HfTiZrSnM (M = Cu, Fe, Nb, Ni). The alloys were characterized crystallographically, microstructurally, and compositionally, and their physical properties were determined, with the emphasis on superconductivity. All Sn-containing alloys are multi-phase mixtures of intermetallic compounds (in most cases four). A common feature of the alloys is a microstructure of large crystalline grains of a hexagonal (Hf, Ti, Zr)5Sn3 partially ordered phase embedded in a matrix that also contains many small inclusions. In the HfTiZrSnCu alloy, some Cu is also incorporated into the grains. Based on the electrical resistivity, specific heat, and magnetization measurements, a superconducting (SC) state was observed in the HfTiZr, HfTiZrSn, HfTiZrSnNi, and HfTiZrSnNb alloys. The HfTiZrSnFe alloy shows a partial SC transition, whereas the HfTiZrSnCu alloy is non-superconducting. All SC alloys are type II superconductors and belong to the Anderson class of “dirty” superconductors.

Point Defects and Diffusion in Nonstoichiometric Metal Oxides

MRS Bulletin ◽  
1991 ◽  
Vol 16 (12) ◽  
pp. 27-32 ◽  
Author(s):  
Rüdiger Dieckmann
Keyword(s):  
Metal Oxides ◽  
Grain Boundaries ◽  
Point Defect ◽  
Point Defects ◽  
Defect Structure ◽  
Ionic Crystals ◽  
Ion Diffusion ◽  
Crystalline Materials ◽  
And Diffusion ◽  
Point Defect Structure

This article briefly reviews the relationships between point defects and ion diffusion in nonstoichiometric ionic crystals, with special emphasis on cubic oxides. It focuses on crystalline materials with negligibly small concentrations of nonequilibrium defects such as dislocations and grain boundaries. First, the concepts used to analyze the point defect structure and the diffusion of ions in nonstoichiometric crystals will be discussed. Then, specific oxides will be considered as examples. These oxides are manganosite, Mn1−ΔO, and spinels of the type Me3−δO4 with Fe and Mn cations, respectively.

Point Defect Detector Studies of Oxidized Silicon

1991 ◽  
Vol 238 ◽  
Author(s):  
H. L. Meng ◽  
K. S. Jones ◽  
S. Prussin
Keyword(s):  
Ion Implantation ◽  
Point Defect ◽  
Point Defects ◽  
Device Fabrication ◽  
Type Ii ◽  
Dislocation Loops ◽  
Plan View ◽  
Atom Concentration ◽  
Enhanced Diffusion ◽  
Transmission Electron

ABSTRACTIon implantation and thermal oxidation are device fabrication processes that lead to perturbation of equilibrium point defects concentration in silicon. This study investigates the interaction between oxidation-induced point defects and type II dislocation loops intentionally introduced in silicon via ion implantation. The type II dislocation loops were introduced via Si implants into (100) Si wafers at 50 keV to a dose ranging from 2×1015 to 1×1016/cm2. The subsequent furnace annealing at 900 °C was done for times between 30 min and 4 hr in either a dry oxygen or nitrogen ambient. Plan-view transmission electron microscopy (PTEM) was used to characterize the increase in atom concentration bound by dislocation loops as a result of oxidation. The results show type II dislocation loops can be used as point defect detector and they are efficient in measuring oxidation-induced point defects. It is also shown that the measured net interstitials flux trapped by dislocation loops is linearly proportional to the total supersaturation of interstitials as measured by oxidation enhanced diffusion (OED) studies.

Detection of a point defect in a silicon single crystal by high-resolution TEM

1995 ◽  
Vol 53 ◽  
pp. 466-467
Author(s):  
M. Awaji
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Point Defect ◽  
Point Defects ◽  
Noise Level ◽  
Dark Field ◽  
Silicon Single Crystal ◽  
High Resolution Image ◽  
Dark Field Imaging ◽  
Field Imaging

It is necessary to improve the resolution, brightness and signal-to-noise ratio(s/n) for the detection and identification of point defects in crystals. In order to observe point defects, multi-beam dark-field imaging is one of the useful methods. Though this method can improve resolution and brightness compared with dark-field imaging by diffuse scattering, the problem of s/n still exists. In order to improve the exposure time due to the low intensity of the dark-field image and the low resolution, we discuss in this paper the bright-field high-resolution image and the corresponding subtracted image with reference to a changing noise level, and examine the possibility for in-situ observation, identification and detection of the movement of a point defect produced in the early stage of damage process by high energy electron bombardment.The high-resolution image contrast of a silicon single crystal in the [10] orientation containing a triple divacancy cluster is calculated using the Cowley-Moodie dynamical theory and for a changing gaussian noise level. This divacancy model was deduced from experimental results obtained by electron spin resonance. The calculation condition was for the lMeV Berkeley ARM operated at 800KeV.

Sign in / Sign up

Export Citation Format

Share Document