The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Paul C. Mcintyre - One of the best experts on this subject based on the ideXlab platform.
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Strain Relaxation mechanisms in compressively Strained thin SiGe-on-insulator films grown by selective Si oxidation
Journal of Applied Physics, 2011Co-Authors: Marika Gunji, Ann F. Marshall, Paul C. McintyreAbstract:We report on Strain Relaxation mechanisms in highly compressive-Strained (0.67%–2.33% biaxial Strain), thin SiGe-on-insulator (SGOI) structures with Ge atomic fraction ranging from 0.18 to 0.81. SGOI layers (8.7–75 nm thickness) were fabricated by selective oxidization of Si from compressively Strained SiGe films epitaxially grown on single crystalline Si-on-insulator (SOI) layers. During high temperature oxidation annealing, Strain Relaxation occurred due to both intrinsic stacking fault (SF) formation and biaxial stress-driven buckling of the SiGe layers through viscous flow of the overlying and underlying SiO2 layers. Transmission electron microscopy (TEM) and x-ray diffraction were performed to confirm the simultaneous occurrence of these two Strain Relaxation mechanisms. The results indicate that ∼30% of the observed Strain Relaxation can be attributed to formation of intrinsic SFs and the remaining Strain Relaxation to stress-driven buckling of the SiGe layers. In addition, cross-sectional TEM image...
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Synthesis and Strain Relaxation of Ge-core/Si-shell nanowire arrays.
Nano letters, 2008Co-Authors: Irene A. Goldthorpe, Ann F. Marshall, Paul C. McintyreAbstract:Analogous to planar heteroepitaxy, misfit dislocation formation and stress-driven surface roughening can relax coherency Strains in misfitting core-shell nanowires. The effects of coaxial dimensions on Strain Relaxation in aligned arrays of Ge-core/Si-shell nanowires are analyzed quantitatively by transmission electron microscopy and synchrotron X-ray diffraction. Relating these results to reported continuum elasticity models for coaxial nanowire heterostructures provides valuable insights into the observed interplay of roughening and dislocation-mediated Strain Relaxation.
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synthesis and Strain Relaxation of ge core si shell nanowire arrays
Nano Letters, 2008Co-Authors: Irene A. Goldthorpe, Ann F. Marshall, Paul C. McintyreAbstract:Analogous to planar heteroepitaxy, misfit dislocation formation and stress-driven surface roughening can relax coherency Strains in misfitting core-shell nanowires. The effects of coaxial dimensions on Strain Relaxation in aligned arrays of Ge-core/Si-shell nanowires are analyzed quantitatively by transmission electron microscopy and synchrotron X-ray diffraction. Relating these results to reported continuum elasticity models for coaxial nanowire heterostructures provides valuable insights into the observed interplay of roughening and dislocation-mediated Strain Relaxation.
Conal E Murray - One of the best experts on this subject based on the ideXlab platform.
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Elastic Strain Relaxation in free-standing SiGe/Si structures
Applied Physics Letters, 2004Co-Authors: P M Mooney, Guy M Cohen, J. O. Chu, Conal E MurrayAbstract:We have investigated elastic Strain Relaxation, i.e., Strain Relaxation without the introduction of dislocations or other defects, in free-standing SiGe/Si structures. We fabricated free-standing Si layers supported at a single point by an SiO2 pedestal and subsequently grew an epitaxial SiGe layer. The measured Strain Relaxation of the SiGe layer agrees well with that calculated using a force-balance model for Strain sharing between the SiGe and Strained Si layers. We report Strained Si layers with biaxial tensile Strain equal to 0.007 and 0.012.
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elastic Strain Relaxation in free standing sige si structures
Applied Physics Letters, 2004Co-Authors: P M Mooney, Guy M Cohen, Conal E MurrayAbstract:We have investigated elastic Strain Relaxation, i.e., Strain Relaxation without the introduction of dislocations or other defects, in free-standing SiGe/Si structures. We fabricated free-standing Si layers supported at a single point by an SiO2 pedestal and subsequently grew an epitaxial SiGe layer. The measured Strain Relaxation of the SiGe layer agrees well with that calculated using a force-balance model for Strain sharing between the SiGe and Strained Si layers. We report Strained Si layers with biaxial tensile Strain equal to 0.007 and 0.012.
S. Mantl - One of the best experts on this subject based on the ideXlab platform.
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Anisotropy of Strain Relaxation in (100) and (110) Si/SiGe heterostructures
Journal of Applied Physics, 2012Co-Authors: H. Trinkaus, Dan Buca, R. A. Minamisawa, Bernhard Holländer, Martina Luysberg, S. MantlAbstract:Plastic Strain Relaxation of SiGe layers of different crystal orientations is analytically analyzed and compared with experimental results. First, Strain Relaxation induced by ion implantation and annealing, considering dislocation loop punching and loop interactions with interfaces/surfaces is discussed. A flexible curved dislocation model is used to determine the relation of critical layer thickness with Strain/stress. Specific critical conditions to be fulfilled, at both the start and end of the Relaxation, are discussed by introducing a quality parameter for efficient Strain Relaxation, defined as the ratio of real to ideal critical thickness versus Strain/stress. The anisotropy of the resolved shear stress is discussed for (001) and (011) crystal orientations in comparison with the experimentally observed anisotropy of Strain Relaxation for Si/SiGe heterostructures.
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Performance enhancement of uniaxially-tensile Strained Si NW-nFETs fabricated by lateral Strain Relaxation of SSOI
2009 10th International Conference on Ultimate Integration of Silicon, 2009Co-Authors: S.f. Feste, Joachim Knoch, S. Habicht, Dan Buca, Qing-tai Zhao, S. MantlAbstract:We present experimental results on mobility enhancement and on-current gain in Si NW-FETs fabricated on SOI and biaxially Strained SOI. In SSOI long channel devices a 2.3 times larger mobility and similar on-current improvement compared to SOI are measured. Measurements on SSOI NW-FETs with different length to width ratio highlight that mobility enhancement due to lateral Strain Relaxation sensitively depends on the device geometry due to the size dependence of lateral Strain Relaxation. For maximum performance enhancement due to lateral Strain Relaxation SSOI devices must have a large length to width ratio. Furthermore, the geometry dependence of lateral Strain Relaxation to achieve uniaxial tensile Strain is investigated with finite element simulations.
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Strain Relaxation of pseudomorphic Si1−xGex/Si(100) heterostructures by Si+ ion implantation
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2005Co-Authors: Bernhard Holländer, Dan Buca, S. Mantl, St. Lenk, H.-j. Herzog, T. Hackbarth, Roger Loo, Matty Caymax, Marcio José Mörschbächer, Paulo Fernando Papaleo FichtnerAbstract:Abstract Strain Relaxation of pseudomorphic Si1−xGex layers (x = 0.21–0.33) grown by chemical vapor deposition or molecular-beam epitaxy on Si(1 0 0) or silicon-on-insulator was investigated after low-fluence Si+ ion implantation and annealing. Strain Relaxation of up to 75% of the initial pseudomorphic Strain was observed at temperatures as low as 850 °C after implantation of Si+ ions with fluences below 2 × 1014 cm−2. We suggest that the Si implantation generates a high density of dislocation loops in the SiGe layer and in the underlying Si, which convert to Strain relaxing misfit segments. The obtained results are comparable to Strain Relaxation achieved after He+ implantation with fluences of 0.7–2 × 1016 cm−2.
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Strain Relaxation mechanism for hydrogen implanted si1 xgex si 100 heterostructures
Applied Physics Letters, 2000Co-Authors: H. Trinkaus, S. Mantl, H.-j. Herzog, B Hollander, St Rongen, J Kuchenbecker, T. HackbarthAbstract:A mechanism of Strain relief of H+ ion implanted and annealed pseudomorphic Si1−xGex/Si(100) heterostructures grown by molecular beam epitaxy is proposed and analyzed. Complete Strain Relaxation was obtained at temperatures as low as 800 °C and the samples appeared free of threading dislocations within the SiGe layer to the limit of transmission electron microscopy analysis. In our model, H filled nanocracks are assumed to generate dislocation loops, which glide to the interface where they form Strain relieving misfit segments. On the basis of this assumption, the conditions for efficient Strain Relaxation are discussed.
P M Mooney - One of the best experts on this subject based on the ideXlab platform.
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Experiments and Modeling of Si-Ge Interdiffusion with Partial Strain Relaxation in Epitaxial SiGe Heterostructures
ECS Journal of Solid State Science and Technology, 2014Co-Authors: Yuanwei Dong, P M Mooney, Feiyang Cai, Dalaver H. Anjum, Naeem Ur-rehman, Xixiang Zhang, Guangrui XiaAbstract:Si-Ge interdiffusion and Strain Relaxation were studied in a metastable SiGe epitaxial structure. With Ge concentration profiling and ex-situ Strain analysis, it was shown that during thermal anneals, both Si-Ge interdiffusion and Strain Relaxation occurred. Furthermore, the time evolutions of both Strain Relaxation and interdiffusion were characterized. It showed that during the ramp-up stage of thermal anneals at higher temperatures (800°C and 840°C), the degree of Relaxation, R, reached a “plateau”, while interdiffusion was negligible. With the approximation that the R value is constant after the ramp-up stage, a quantitative interdiffusivity model was built to account for both the effect of Strain Relaxation and the impact of the Relaxation induced dislocations, which gave good agreement with the experiment data
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Elastic Strain Relaxation in free-standing SiGe/Si structures
Applied Physics Letters, 2004Co-Authors: P M Mooney, Guy M Cohen, J. O. Chu, Conal E MurrayAbstract:We have investigated elastic Strain Relaxation, i.e., Strain Relaxation without the introduction of dislocations or other defects, in free-standing SiGe/Si structures. We fabricated free-standing Si layers supported at a single point by an SiO2 pedestal and subsequently grew an epitaxial SiGe layer. The measured Strain Relaxation of the SiGe layer agrees well with that calculated using a force-balance model for Strain sharing between the SiGe and Strained Si layers. We report Strained Si layers with biaxial tensile Strain equal to 0.007 and 0.012.
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elastic Strain Relaxation in free standing sige si structures
Applied Physics Letters, 2004Co-Authors: P M Mooney, Guy M Cohen, Conal E MurrayAbstract:We have investigated elastic Strain Relaxation, i.e., Strain Relaxation without the introduction of dislocations or other defects, in free-standing SiGe/Si structures. We fabricated free-standing Si layers supported at a single point by an SiO2 pedestal and subsequently grew an epitaxial SiGe layer. The measured Strain Relaxation of the SiGe layer agrees well with that calculated using a force-balance model for Strain sharing between the SiGe and Strained Si layers. We report Strained Si layers with biaxial tensile Strain equal to 0.007 and 0.012.
Ann F. Marshall - One of the best experts on this subject based on the ideXlab platform.
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Strain Relaxation mechanisms in compressively Strained thin SiGe-on-insulator films grown by selective Si oxidation
Journal of Applied Physics, 2011Co-Authors: Marika Gunji, Ann F. Marshall, Paul C. McintyreAbstract:We report on Strain Relaxation mechanisms in highly compressive-Strained (0.67%–2.33% biaxial Strain), thin SiGe-on-insulator (SGOI) structures with Ge atomic fraction ranging from 0.18 to 0.81. SGOI layers (8.7–75 nm thickness) were fabricated by selective oxidization of Si from compressively Strained SiGe films epitaxially grown on single crystalline Si-on-insulator (SOI) layers. During high temperature oxidation annealing, Strain Relaxation occurred due to both intrinsic stacking fault (SF) formation and biaxial stress-driven buckling of the SiGe layers through viscous flow of the overlying and underlying SiO2 layers. Transmission electron microscopy (TEM) and x-ray diffraction were performed to confirm the simultaneous occurrence of these two Strain Relaxation mechanisms. The results indicate that ∼30% of the observed Strain Relaxation can be attributed to formation of intrinsic SFs and the remaining Strain Relaxation to stress-driven buckling of the SiGe layers. In addition, cross-sectional TEM image...
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Synthesis and Strain Relaxation of Ge-core/Si-shell nanowire arrays.
Nano letters, 2008Co-Authors: Irene A. Goldthorpe, Ann F. Marshall, Paul C. McintyreAbstract:Analogous to planar heteroepitaxy, misfit dislocation formation and stress-driven surface roughening can relax coherency Strains in misfitting core-shell nanowires. The effects of coaxial dimensions on Strain Relaxation in aligned arrays of Ge-core/Si-shell nanowires are analyzed quantitatively by transmission electron microscopy and synchrotron X-ray diffraction. Relating these results to reported continuum elasticity models for coaxial nanowire heterostructures provides valuable insights into the observed interplay of roughening and dislocation-mediated Strain Relaxation.
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synthesis and Strain Relaxation of ge core si shell nanowire arrays
Nano Letters, 2008Co-Authors: Irene A. Goldthorpe, Ann F. Marshall, Paul C. McintyreAbstract:Analogous to planar heteroepitaxy, misfit dislocation formation and stress-driven surface roughening can relax coherency Strains in misfitting core-shell nanowires. The effects of coaxial dimensions on Strain Relaxation in aligned arrays of Ge-core/Si-shell nanowires are analyzed quantitatively by transmission electron microscopy and synchrotron X-ray diffraction. Relating these results to reported continuum elasticity models for coaxial nanowire heterostructures provides valuable insights into the observed interplay of roughening and dislocation-mediated Strain Relaxation.
