Hydrogen in Crystalline Silicon under Compression and Tension

MRS Proceedings ◽

10.1557/proc-163-425 ◽

1989 ◽

Vol 163 ◽

Author(s):

C.S. Nichols ◽

D.R. Clarke

Keyword(s):

Tensile Stress ◽

Charge State ◽

First Principles ◽

Crystalline Silicon ◽

Hydrogen Charge ◽

Interstitial Site ◽

Crystalline Lattice ◽

Bond Center ◽

Crack Tips ◽

Center Site

AbstractThe behavior of hydrogen in crystalline silicon (c-Si) containing regions of compressive or tensile stress is important for understanding the solute’s interaction with dislocations, grain boundaries, and crack tips. A series of first-principles total-energy calculations probing the stable site for hydrogen as a function of its charge state, the Fermi level position, and the crystalline lattice constant has been performed. We find that the stable site for hydrogen depends critically on both pressure and on the hydrogen charge state. Furthermore, hydrogen is predicted to undergo a transition from an interstitial site to the bond-center site as a function of pressure.

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First-Principles Calculations Of Diffusion Of Chlorine Atoms In GaAs

MRS Proceedings ◽

10.1557/proc-442-529 ◽

1996 ◽

Vol 442 ◽

Author(s):

Takahisa Ohno ◽

Taizo Sasaki ◽

Akihito Taguchi

Keyword(s):

Fermi Level ◽

Charge State ◽

First Principles ◽

Interstitial Site ◽

High Electron ◽

Chlorine Atoms ◽

Tetrahedral Interstitial Site ◽

Bond Center ◽

Cl Atom ◽

Center Site

AbstractThe properties of chlorine atoms in crystalline GaAs, such as stable configurations, migration paths, charge-state effects, and interaction with dopant atoms are theoretically investigated. The calculations are based on the local density functional theory using first-principles pseudopotentials in a supercell geometry. We determine the stable charge state of an isolated Cl atom as a function of the Fermi energy. When the Fermi level is situated at the top of the valence band of GaAs, the Cl atom occupies preferentially the bond-center site of a Ga-As bond in the positive charge state. The Cl atom diffuses through the GaAs crystal via a path in the region of high electron density, with a fairly large energy barrier. When the Fermi level is at the bottom of the conduction band, the lowest-energy configuration of the Cl atom is the tetrahedral interstitial site in the negative charge state and the bond center site is very slightly higher in energy. In Si-doped GaAs, the C1 atom occupies the tetrahedral interstitial site with the substitutional Si donor atom as a nearest neighbor, forming a neutral Cl-Si complex. The Cl-Si complex is weak and easily dissociates into the isolated C1 and Si atoms in GaAs. A comparison will be made between the behavior of Cl and F atoms in GaAs.

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The Structure of the Boron-Hydrogen Complex in Silicon

MRS Proceedings ◽

10.1557/proc-104-259 ◽

1987 ◽

Vol 104 ◽

Cited By ~ 14

Author(s):

A. D. Marwick ◽

G. S. Oehrlein ◽

J. H. Barrett ◽

N. M Johnson

Keyword(s):

Monte Carlo ◽

Hydrogen Atom ◽

Monte Carlo Simulations ◽

Boron Atom ◽

Small Proportion ◽

Crystalline Silicon ◽

Hydrogen Atoms ◽

Substitutional Site ◽

Bond Center ◽

Center Site

ABSTRACTChanneling and lattice location has been used to investigate the structure of the boron-hydrogen complex in crystalline silicon. The positions of both the boron and hydrogen atoms have been determined. The results are compared with Monte-Carlo simulations. The boron atom in the B-H pair is found to be displaced from a substitutional site by 0.28±0.03Å, while the hydrogen atom is predominantly at a bond-center site, with a small proportion in a back-bonded position.

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Electronic Structure and Hyperfine Parameters for Hydrogen and Muonium in Silicon

MRS Proceedings ◽

10.1557/proc-163-419 ◽

1989 ◽

Vol 163 ◽

Author(s):

Chris G. Van De Walle

Keyword(s):

Spin Density ◽

First Principles ◽

Density Functional Calculations ◽

Density Functional ◽

Muon Spin ◽

Spin Rotation ◽

Muon Spin Rotation ◽

Hyperfine Parameters ◽

Bond Center ◽

Center Site

AbstractFirst-principles spin-density-functional calculations are used to evaluate hyperfine and superhyperfine parameters for hydrogen and muonium at various sites in the Si lattice. The results can be directly compared with values from muon-spin-rotation experiments, leading to an unambiguous identification of “anomalous muonium” with the bond-center site. The agreement found in this case instills confidence in the general use of spin-density-functional calculations for predicting hyperfine parameters of defects.

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Diffusion of Fluorine-Silicon Interstitial Complex in Crystalline Silicon

MRS Proceedings ◽

10.1557/proc-864-e9.1 ◽

2005 ◽

Vol 864 ◽

Author(s):

Scott A. Harrison ◽

Thomas F. Edgar ◽

Gyeong S. Hwang

Keyword(s):

Density Functional Theory ◽

Binding Energy ◽

Charge State ◽

First Principles ◽

Density Functional ◽

Positive Charge ◽

Crystalline Silicon ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

And Diffusion

AbstractBased on first principles density functional theory calculations, we identify the structure and diffusion pathway for a fluorine-silicon interstitial complex (F-Sii). We find the F-Sii complex to be most stable in the singly positive charge state at all Fermi leVels. At mid-gap, the complex is found to have a binding energy of 1.08 eV relative to bond-centered F+ and (110)-split Sii. We find the F-Sii complex has an overall migration barrier of 0.76 eV, which suggests that this complex may play an important role in fluorine diffusion. Our results should lead to more accurate models that describe the behavior of fluorine co-implants crystalline silicon.

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Effect of Boron and Hydrogen on the Electronic Structure of Ni3Al

MRS Proceedings ◽

10.1557/proc-319-363 ◽

1993 ◽

Vol 319 ◽

Cited By ~ 2

Author(s):

N. Kioussis ◽

H. Watanabe ◽

R.G. Hemker ◽

W. Gourdin ◽

A. Gonis ◽

...

Keyword(s):

Electronic Structure ◽

Charge Density ◽

First Principles ◽

Electronic Structure Calculations ◽

Interstitial Site ◽

Octahedral Interstitial Site ◽

Interstitial Region ◽

Ordered Intermetallic ◽

Lmto Method ◽

Structure Calculations

AbstractUsing first-principles electronic structure calculations based on the Linear-Muffin-Tin Orbital (LMTO) method, we have investigated the effects of interstitial boron and hydrogen on the electronic structure of the L12 ordered intermetallic Ni3A1. When it occupies an octahedral interstitial site entirely coordinated by six Ni atoms, we find that boron enhances the charge distribution found in the strongly-bound “pure” Ni3AI crystal: Charge is depleted at Ni and Al sites and enhanced in interstitial region. Substitution of Al atoms for two of the Ni atoms coordinating the boron, however, reduces the interstitial charge density between certain atomic planes. In contrast to boron, hydrogen appears to deplete the interstitial charge, even when fully coordinated by Ni atoms. We suggest that these results are broadly consistent with the notion of boron as a cohesion enhancer and hydrogen as an embrittler.

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First-Principles Assessment of the Structure and Stability of 15 Intrinsic Point Defects in Zinc-Blende Indium Arsenide

Crystals ◽

10.3390/cryst9010048 ◽

2019 ◽

Vol 9 (1) ◽

pp. 48 ◽

Cited By ~ 2

Author(s):

Qing Peng ◽

Nanjun Chen ◽

Danhong Huang ◽

Eric Heller ◽

David Cardimona ◽

...

Keyword(s):

Fermi Level ◽

Charge State ◽

Indium Arsenide ◽

Point Defects ◽

First Principles ◽

Formation Energy ◽

Fast Diffusion ◽

Intrinsic Point Defects ◽

Zinc Blende ◽

Tetrahedral Sites

Point defects are inevitable, at least due to thermodynamics, and essential for engineering semiconductors. Herein, we investigate the formation and electronic structures of fifteen different kinds of intrinsic point defects of zinc blende indium arsenide (zb-InAs ) using first-principles calculations. For As-rich environment, substitutional point defects are the primary intrinsic point defects in zb-InAs until the n-type doping region with Fermi level above 0.32 eV is reached, where the dominant intrinsic point defects are changed to In vacancies. For In-rich environment, In tetrahedral interstitial has the lowest formation energy till n-type doped region with Fermi level 0.24 eV where substitutional point defects In A s take over. The dumbbell interstitials prefer < 110 > configurations. For tetrahedral interstitials, In atoms prefer 4-As tetrahedral site for both As-rich and In-rich environments until the Fermi level goes above 0.26 eV in n-type doped region, where In atoms acquire the same formation energy at both tetrahedral sites and the same charge state. This implies a fast diffusion along the t − T − t path among the tetrahedral sites for In atoms. The In vacancies V I n decrease quickly and monotonically with increasing Fermi level and has a q = − 3 e charge state at the same time. The most popular vacancy-type defect is V I n in an As-rich environment, but switches to V A s in an In-rich environment at light p-doped region when Fermi level below 0.2 eV. This study sheds light on the relative stabilities of these intrinsic point defects, their concentrations and possible diffusions, which is expected useful in defect-engineering zb-InAs based semiconductors, as well as the material design for radiation-tolerant electronics.

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First-Principles Investigation of Atomic Hydrogen Adsorption and Diffusion on/into Mo-doped Nb (100) Surface

Applied Sciences ◽

10.3390/app8122466 ◽

2018 ◽

Vol 8 (12) ◽

pp. 2466 ◽

Cited By ~ 7

Author(s):

Yang Wu ◽

Zhongmin Wang ◽

Dianhui Wang ◽

Jiayao Qin ◽

Zhenzhen Wan ◽

...

Keyword(s):

First Principles ◽

Atomic Hydrogen ◽

Energy Barrier ◽

Hydrogen Adsorption ◽

Hydrogen Permeation ◽

Diffusion Path ◽

Interstitial Site ◽

Octahedral Interstitial Site ◽

Tetrahedral Interstitial Site ◽

And Diffusion

To investigate Mo doping effects on the hydrogen permeation performance of Nb membranes, we study the most likely process of atomic hydrogen adsorption and diffusion on/into Mo-doped Nb (100) surface/subsurface (in the Nb12Mo4 case) via first-principles calculations. Our results reveal that the (100) surface is the most stable Mo-doped Nb surface with the smallest surface energy (2.75 J/m2). Hollow sites (HSs) in the Mo-doped Nb (100) surface are H-adsorption-favorable mainly due to their large adsorption energy (−4.27 eV), and the H-diffusion path should preferentially be HS→TIS (tetrahedral interstitial site) over HS→OIS (octahedral interstitial site) because of the correspondingly lower H-diffusion energy barrier. With respect to a pure Nb (100) surface, the Mo-doped Nb (100) surface has a smaller energy barrier along the HS→TIS pathway (0.31 eV).

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p-Type conductivity mechanism and defect structure of nitrogen-doped LiNbO3 from first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05019a ◽

2020 ◽

Vol 22 (1) ◽

pp. 20-27 ◽

Cited By ~ 2

Author(s):

Weiwei Wang ◽

Yang Zhong ◽

Dahuai Zheng ◽

Hongde Liu ◽

Yongfa Kong ◽

...

Keyword(s):

Charge State ◽

First Principles ◽

Defect Structure ◽

State Transition ◽

First Principles Calculations ◽

Type Conductivity ◽

Nitrogen Doped ◽

Conductivity Mechanism ◽

Transition Level ◽

P Type

The charge-state transition level and geometry structure of non-metallic N-doped LiNbO3 are calculated by DFT, which reveal the p-type conductivity mechanism of LiNbO3:N.

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Nonequilibrium processes for generating silicon nanostructures in single-crystalline silicon

Pure and Applied Chemistry ◽

10.1351/pac200274091631 ◽

2002 ◽

Vol 74 (9) ◽

pp. 1631-1641 ◽

Cited By ~ 4

Author(s):

P. Sen ◽

J. Akhtar

Keyword(s):

Vibrational Energy ◽

Crystalline Silicon ◽

Ion Irradiation ◽

Heavy Ion ◽

High Energy ◽

Crystalline Lattice ◽

Periodic Lattice ◽

Silicon Nanostructures ◽

Nonlinear Transport ◽

Single Crystalline

The possibility of modifying existing materials through technology has become the recipe for preparation of advanced materials. Nonequilibrium processing of silicon through MeV ion irradiation will be shown here to yield interesting properties. We propose localization of vibrational energy following an ion irradiation process and their transport (nonlinear transport of energy) through linear chains of a single-crystalline lattice. The localization of energy can involve 34 atoms, and, hence, nanometer-sized entities evolve, distinguishable from the remaining periodic lattice owing to their unique interatomic distances. The energy required to produce these structures is supplied by a single high-energy heavy ion, incident normal to a suitable crystal face so as to lose energy by the electronic energy loss mechanism. These entities can be trapped at a desired location that leads to silicon nanostructures with modified band-gaps.

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