Partial dislocations in the wurtzite lattice

Osip’yan, Yu. A.; Смирнова, И. С.

doi:10.1016/s0022-3697(71)80046-x

Cited by 23 publications

(12 citation statements)

References 12 publications

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“…3. There are several possibilities that could lead to the formation of this kind of fault in the wurtzite lattice, including the removal of a double layer from distant atoms of the aA type, or the removal of a double layer from neighboring atoms of the Ab or Ba types [37]. These faults are bordered by Frank partial dislocations.…”

Section: Structure and Microstructure Of The Zno Substratesmentioning

confidence: 99%

Homoepitaxial growth of (0001)- and -oriented ZnO thin films via metalorganic vapor-phase epitaxy and their characterization

Smith

Mclean

Smith

et al. 2004

Journal of Crystal Growth

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Section: Structure and Microstructure Of The Zno Substratesmentioning

confidence: 99%

Homoepitaxial growth of (0001)- and -oriented ZnO thin films via metalorganic vapor-phase epitaxy and their characterization

Smith

Mclean

Smith

et al. 2004

Journal of Crystal Growth

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“…Instead of using the four Miller-Bravais indices for HCP, the coordinates of atomic positions in HCP are indexed with three orthogonal axes, using a double-tetrahedral notation similar to the Thompson Tetrahedral for FCC [2,4]. Two long straight dislocations  1 and  2 gliding with different slip systems intersect each other at the midpoint.…”

Section: Simulation Methodsmentioning

confidence: 99%

“…Instead of unanimously gliding on the close-packed basal planes (0001) as all dislocations do in FCC and BCC, the slip systems for dislocations in HCP also involve higher-order non-basal slip planes including {1 0 -1 0} prismatic, first-order {10-11} pyramidal, and second-order {11-22} pyramidal slip planes, and several possible Burgers vectors including <11-20>, <0001>, or <11-2-3> [1][2]. Despite of these complexities, the HCP structure and all slip systems and cross-slip planes can still be conveniently described by employing a simple three-index orthogonal coordinate system based on the double tetrahedron notation for DD simulations [3][4]. In plastic deformation, dislocation junctions can form energetically (the so called "zipping" phenomena) but also can be destroyed via "unzipping" by an applied stress [5][6][7][8][9][10][11][12][13][14][15].…”

Section: Introductionmentioning

confidence: 99%

Dislocation Dynamics Simulations of Junctions in Hexagonal Close-Packed Crystals

Aubry

Chung

et al. 2012

MRS Proc.

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The formation and strength of dislocations in the hexagonal closed packed material beryllium are studied through dislocation junctions and the critical stress required to break them.Dislocation dynamics calculations (using the code ParaDiS) of junction maps are compared to an analytical line tension approximation in order to validate our model. Results show that the two models agree very well. Also the critical shear stress necessary to break 30 o -30 o and 30 o -90 o dislocation junctions is computed numerically. Yield surfaces are mapped out for these junctions to describe their stability regions as function of resolved shear stresses on the glide planes.The example of two non-coplanar binary dislocation junctions with slip planes [2-1-10] (01-10) and [-12-10] (0001) corresponding to a prismatic and basal slip respectively is chosen to verify and validate our implementation.

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“…Because the current version of the code was originally designed for modeling perfect dislocations in bulk hcp crystals, several slip systems that are important to wurtzite but do not exist in hcp crystals are not included, such as the a-planes , the r-plane , and the type Burgers vectors (23). In addition, partial dislocations can exist in wurtzite crystals (24,25) and have been found frequently in III-V wurtzite semiconductors in experiments (e.g., reference 26). Furthermore, experimental findings have also indicated a possible dependence of dislocation velocity on the slip systems.…”

Section: Wurtzite Ganmentioning

confidence: 99%

“…This would stabilize the ZB phase if the reduction in the energy of forming this phase to create shorter dislocations without creating stacking faults is greater than the increase in the energy of formation of this phase. These PDs are Frank partials, which are formed during growth when, e.g., a segment of an Aα double layer is replaced by a Cγ segment or a αB segment is replaced by a γC double layer (24). Unlike glissile Shockley dislocations such as those formed by the decomposition of a 60° basal plane dislocation in which the b i make an angle of 30° or 90° with l, these PDs are sessile and they make angles of arcos[±1/(4 + 3γ 2 ) ½ ] with l.…”

Section: Derivation Of Most Probable Slip Systemsmentioning

confidence: 99%

Control of Defects in Aluminum Gallium Nitride ((Al)GaN) Films on Grown Aluminum Nitride (AlN) Substrates

Batyrev¹,

Wu²,

Chung³

et al. 2013

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Sensors and Electron Devices Directorate, ARLApproved for public release; distribution unlimited. ii REPORT DOCUMENTATION PAGEForm Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY)February 2013 ARL-TR-6350 SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S) SPONSOR/MONITOR'S REPORT NUMBER(S) DISTRIBUTION/AVAILABILITY STATEMENTApproved for public release; distribution unlimited. SUPPLEMENTARY NOTES ABSTRACTWe present efforts aimed at establishing a multiscale approach for simulating dislocations in aluminum gallium nitride ((Al)GaN) semiconductors. We performed quantum mechanical and classical molecular dynamics (MD) simulations to study the electronic and atomic structure of threading edge and screw dislocations in AlGaN, focusing on the structure of the dislocation core and the electrical activity of dislocations, and estimating dislocation velocities as a function of applied stress and temperature. We used the calculated mobility functions from MD to study different junction configurations using a discrete dislocation dynamics (DDD) simulator, ParaDiS. Finally, we predicted the most likely slip planes in wurtzite (Al)GaN semiconductors based on general crystallographic principles. The most important results are (1) aluminum (Al) atoms do not segregate to the dislocation core and atoms in the dislocation core do not produce any defect levels in the bandgap; (2) we performed first time classical MD calculations of dislocation velocity as a function of applied stress for three slip systems in gallium nitride (GaN); (3) we adapted ParaDiS to simulate wurtzite semiconductors; and (4) the plane strain produced by the lattice mismatch during growth on the plane does not create a shear stress on the basal or prismatic planes, hence the operational slip plane must be a pyramidal plane, the most probable being the slip system. iii Contents SUBJECT TERMS

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Partial dislocations in the wurtzite lattice

Cited by 23 publications

References 12 publications

Homoepitaxial growth of (0001)- and -oriented ZnO thin films via metalorganic vapor-phase epitaxy and their characterization

Homoepitaxial growth of (0001)- and -oriented ZnO thin films via metalorganic vapor-phase epitaxy and their characterization

Dislocation Dynamics Simulations of Junctions in Hexagonal Close-Packed Crystals

Control of Defects in Aluminum Gallium Nitride ((Al)GaN) Films on Grown Aluminum Nitride (AlN) Substrates

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