Download or read book Ion induced Damage and Amorphization in Si written by and published by . This book was released on 1990 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ion-induced damage growth in high-energy, self-ion irradiated Si was studied using electron microscopy and Rutherford backscattering spectroscopy. The results show that there is a marked variation in the rate of damage growth, as well as the damage morphology, along the path of the ion. Near the ion end-of-range (eor), damage increases monotonically with ion fluence until a buried amorphous layer is formed, while damage growth saturates at a low level in the region ahead. The morphology of the damage in the saturated region is shown to consist predominantly of simple defect clusters such as the divacancy. Damage growth remains saturated ahead of the eor until expansion of the buried amorphous layer encroaches into the region. A homogeneous growth model is presented which accounts for damage saturation, and accurately predicts the dose-rate dependence of the saturation level. Modifications of the model are discussed which are needed to account for the rapid growth in the eor region and near the interface of the buried amorphous layer. Two important factors contributing to rapid damage growth are identified. Spatial separation of the Frenkel defect pairs (i.e. interstitials and vacancies) due to the momentum of the interstitials is shown to greatly impact damage growth near the eor, while uniaxial strain in the interfacial region of the amorphous layer is identified as an important factor contributing to growth at that location. 20 refs., 10 figs.
Download or read book Ion Implantation Induced Defect Formation and Amorphization in the Group IV Semiconductors written by Diane P. Hickey and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Damage in Si and Ge was produced by Si implantation at 40 keV to a dose of 1 x 1014 cm−2 and 1 x 1015 cm−2, and amorphizing damage in diamond was produced by Si implantation at 1 MeV to a dose of 3 and 7 x 1015 cm−2. All implants were carried out at room temperature. For non-amorphizing implants (1014 Si+ cm−2) into Ge, dot-like defects formed immediately upon implantation and were stable up to temperatures of 650 °C. The activation energy of these defects was determined to be approximately 0.2 " 0.1 eV. For amorphizing implants (1015 Si+ cm−2) into Ge and upon solid-phase epitaxial regrowth, the same types of defects seen in Si were also seen in Ge. However, in Ge, the end-of-range defects were the least stable, dissolving at temperatures around 650 °C. The activation energy for the dissolution of end-of-range defects in Ge is approximately 0.4 " 0.1 eV. For diamond, non-amorphizing Si+ implantation (
Download or read book The Formation of Amorphous Silicon by Light Ion Damage written by Yih-Cheng Shih and published by . This book was released on 1986 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Amorphization and the Effect of Implanted Ions in SiC written by and published by . This book was released on 1994 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of implanted ion chemistry and displacement damage on the amorphization threshold dose of SiC were studied using cross-section transmission electron microscopy. Room temperature as well as 200 and 400 C irradiations were carried out with 3.6 MeV Fe, 1.8 MeV Cl, 1 MeV He or 0.56 MeV Si ions. The room temperature amorphization threshold dose in irradiated regions well separated from the implanted ions was found to range from 0.3 to 0.5 dpa for the four different ion species. The threshold dose for amorphization in the He, Si and Fe ion-implanted regions was also (approximately)0.3 to 0.5 dpa. On the other hand, the amorphization threshold in the Cl-implanted region was only about 0.1 dpa. The volume change associated with amorphization was (approximately)17%. No evidence for amorphization was obtained in specimens irradiated at 200 or 400 C. An understanding of the microstructural evolution of SiC under irradiation is critical to the application of these materials in fusion energy systems.
Download or read book Amorphous damage Depth Distributions and the Amorphization of Silicon by Ion Bombardment written by Joseph Sadowski and published by . This book was released on 1980 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ion Beams in Materials Processing and Analysis written by Bernd Schmidt and published by Springer Science & Business Media. This book was released on 2012-12-13 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive review of ion beam application in modern materials research is provided, including the basics of ion beam physics and technology. The physics of ion-solid interactions for ion implantation, ion beam synthesis, sputtering and nano-patterning is treated in detail. Its applications in materials research, development and analysis, developments of special techniques and interaction mechanisms of ion beams with solid state matter result in the optimization of new material properties, which are discussed thoroughly. Solid-state properties optimization for functional materials such as doped semiconductors and metal layers for nano-electronics, metal alloys, and nano-patterned surfaces is demonstrated. The ion beam is an important tool for both materials processing and analysis. Researchers engaged in solid-state physics and materials research, engineers and technologists in the field of modern functional materials will welcome this text.
Download or read book Effect of Mass and Energy on Preferential Amorphization in Polycrystalline Silicon Film During Ion Irradiation written by S. Watanebe and published by . This book was released on 2001 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: In-situ transmission electron microscopy was applied for clarifying radiation-induced amorphization, the behavior of grain boundaries under ion irradiation. The effect of mass and energy of several ions on preferential amorphization was discussed. The critical fluence for amorphization strongly depended on the temperature, where it increased with increasing temperature. Further, with increasing ion mass and decreasing energy, the critical fluence was reduced. The onset temperature for preferential amorphization increased in the case of heavier mass and lower energy ion irradiation. All of the results imply the importance of the balance between damage production and recovery.
Download or read book Direct Simulation of Ion Beam Induced Stressing and Amorphization of Silicon written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using molecular dynamics (MD) simulation, the authors investigate the mechanical response of silicon to high dose ion-irradiation. The authors employ a realistic model to directly simulate ion beam induced amorphization. Structural properties of the amorphized sample are compared with experimental data and results of other simulation studies. The authors find the behavior of the irradiated material is related to the rate at which it can relax. Depending upon the ability to deform, the authors observe either the generation of a high compressive stress and subsequent expansion of the material, or generation of tensile stress and densification. The authors note that statistical material properties, such as radial distribution functions are not sufficient to differentiate between the different densities of the amorphous samples. For any reasonable deformation rate, the authors observe an expansion of the target upon amorphization in agreement with experimental observations. This is in contrast to simulations of quenching which usually result in a denser structure relative to crystalline Si. The authors conclude that although there is substantial agreement between experimental measurements and simulation results, the amorphous structures being investigated may have fundamental differences; the difference in density can be attributed to local defects within the amorphous network. Finally the authors show that annealing simulations of their amorphized samples can lead to a reduction of high energy local defects without a large scale rearrangement of the amorphous network. This supports the proposal that defects in a-Si are analogous to those in c-Si.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of Semiconductor Processes and Devices 2001 written by Dimitris Tsoukalas and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the Proceedings of the International Conference on Simulation of Semiconductor Devices and Processes, SISPAD 01, held on September 5–7, 2001, in Athens. The conference provided an open forum for the presentation of the latest results and trends in process and device simulation. The trend towards shrinking device dimensions and increasing complexity in process technology demands the continuous development of advanced models describing basic physical phenomena involved. New simulation tools are developed to complete the hierarchy in the Technology Computer Aided Design simulation chain between microscopic and macroscopic approaches. The conference program featured 8 invited papers, 60 papers for oral presentation and 34 papers for poster presentation, selected from a total of 165 abstracts from 30 countries around the world. These papers disclose new and interesting concepts for simulating processes and devices.
Download or read book Ion Beam Modification of Solids written by Werner Wesch and published by Springer. This book was released on 2016-07-14 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the method of ion beam modification of solids in realization, theory and applications in a comprehensive way. It provides a review of the physical basics of ion-solid interaction and on ion-beam induced structural modifications of solids. Ion beams are widely used to modify the physical properties of materials. A complete theory of ion stopping in matter and the calculation of the energy loss due to nuclear and electronic interactions are presented including the effect of ion channeling. To explain structural modifications due to high electronic excitations, different concepts are presented with special emphasis on the thermal spike model. Furthermore, general concepts of damage evolution as a function of ion mass, ion fluence, ion flux and temperature are described in detail and their limits and applicability are discussed. The effect of nuclear and electronic energy loss on structural modifications of solids such as damage formation, phase transitions and amorphization is reviewed for insulators and semiconductors. Finally some selected applications of ion beams are given.
Download or read book On the Amorphization of Si and WO3 by Particle Impact Studies on Bombardment induced Disorder V written by Roger Kelly and published by . This book was released on 1971 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Estimates of the depth of bombardment-induced amorphization (R sub a) are presently available for seven different ions injected into Si(Ar, As, B, Ne, P, Sb and Si) as well as for Kr injected into WO3. These depths can be interpreted in terms of recent damage-distribution theories to yield F sub d(R sub a), the initial displacement fraction at depth R sub a. (Here the term 'initial' means 'present before thermal and athermal annealing'.) The resulting values of F sub d(R sub a) were found to be reasonably constant, such that, depending on which theory was used, they had an average of either 0.7 plus or minus 0.2 or 0.4 plus or minus 0.2 for Si and either 0.9 plus or minus 0.03 or 0.17 plus or minus 0.06 for WO3. It is concluded, in view of the constancy of F sub d(R sub a), that the amorphization of Si and WO3 can be self-consistently explained by homogeneous damage accumulation. (Author Modified Abstract).
Download or read book Pre amorphization Damage in Ion implanted Silicon written by Robert Jan Schreutelkamp and published by . This book was released on 1991 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Formation of Amorphous Silicon by Light Ion Damage written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Amorphization by implantation of boron ions (which is the lightest element generally used in I.C. fabrication processes) has been systematically studied for various temperatures, various voltages and various dose rates. Based on theoretical considerations and experimental results, a new amorphization model for light and intermediate mass ion damage is proposed consisting of two stages. The role of interstitial type point defects or clusters in amorphization is emphasized. Due to the higher mobility of interstitials out-diffusion to the surface particularly during amorphization with low energy can be significant. From a review of the idealized amorphous structure, diinterstitial-divacancy pairs are suggested to be the embryos of amorphous zones formed during room temperature implantation. The stacking fault loops found in specimens implanted with boron at room temperature are considered to be the origin of secondary defects formed during annealing.
Download or read book Ion Solid Interactions written by Michael Nastasi and published by Cambridge University Press. This book was released on 1996-03-29 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive guide to an important materials science technique for students and researchers.
Download or read book Swift Heavy Ion Irradiation of Amorphous Ge Amorphous Si and Amorphous Si1 xgex Alloys written by Thomas Bierschenk and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interaction of swift heavy ions (SHIs) with solids is characterised by inelastic collisions between the ions and the target electrons. SHIs typically deposit tens of keV/nm of energy in the target material causing extreme excitation of the electronic subsystem that result in different damage formation mechanisms than for ion implantation such as the formation of ion tracks, plastic deformation or porous layer formation. The crystalline phases of the elemental semiconductors Ge and Si are relatively resistant to SHI irradiation induced damage. In contrast, their amorphous counterparts (a-Ge and a-Si, respectively) are subject to SHI irradiation induced plastic deformation and porous layer formation. The former is caused by ion hammering and entirely predicated on the creation of ion tracks and thus provides indirect evidence for ion-track formation in a-Ge and a-Si. SHI irradiation was performed on a-Ge, a-Si and amorphous Si(1-x)Ge(x) (a-Si(1-x)Ge(x)) with different stoichiometries to study the study ion-track and porous layer formation in these materials. Synchrotron-based small-angle x-ray scattering was utilised to characterise the structure of ion tracks in the amorphous materials and the formation of nanoporosity was investigated by scanning electron microscopy. The experimental observations were complemented by a novel theoretical approach comprising a Monte Carlo calculation of the electron dynamics, a Two-Temperature Model description of the heat dissipation, and Molecular Dynamics simulations of the atom dynamics. Ion-track formation has been identified for a-Ge, a-Si and a-Si(1-x)Ge(x) alloys. While SHI irradiation of all such materials results in the formation of overall densified ion tracks with an underlying core-shell morphology, different mechanisms for the formation of ion tracks are revealed. Ion tracks in a-Ge are comprised of an under-dense shell surrounded by an over-dense core. The formation of ion-tracks is accompanied by the formation of non-spherical voids which are identified as the precursors for the porous layer formation under continuing SHI irradiation. On the contrary, ion tracks in a-Si and a-Si(1-x)Ge(x) alloys feature a dominant over-dense core surrounded by an under-dense shell. The formation of non-spherical voids was observed for a-Si(0.2)Ge(0.8), however, voids are absent in all other SHI irradiated alloys and a-Si. Continuous SHI irradiation leads to the formation of porosity in a-Ge, a-Si and a-Si(1-x)Ge(x) alloys. In a-Ge and Ge-rich a-Si(1-x)Ge(x) alloys, self-organisation of pores into well separated porous layers occurs. The layering effect depends on the irradiation energy, angle of incidence and thickness of the amorphous layer. SHI irradiation induced void formation in a-Si occurs at much higher ion fluences relative to a-Ge. In contrast to a-Ge, no self-organisation of pores is apparent in a-Si and the voids exhibit a cavity-like morphology, which implies a different void formation mechanism in the two elemental semiconductors. The results on ion-track and porous layer formation in a-Ge, a-Si and a-Si(1-x)Ge(x) alloys shed new light on the damage evolution in amorphous semiconductors due to high electronic excitation and may provide a pathway for the development of novel materials.
Download or read book A Mechanistic Model for Radiation induced Crystallization and Amorphization in U3Si written by and published by . This book was released on 1994 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiation-induced amorphization is assessed. A rate-theory model is formulated wherein amorphous clusters are formed by the damage event These clusters are considered centers of expansion (CE), or excess-free-volume zones. Simultaneously, centers of compression (CC) are created in the material. The CCs are local regions of increased density that travel through the material as an elastic (e.g., acoustic) shock wave. The CEs can be annihilated upon contact with CCs (annihilation probability depends on height of the energy barrier), forming either a crystallized region indistinguishable from the host material, or a region with a slight disorientation (recrystallized grain). Recrystallized grains grow by the accumulation of additional CCs. Full amorphization is calculated on the basis of achieving a fuel volume fraction consistent with the close packing of spherical entities. Amorphization of a recrystallized grain is hindered by the grain boundary. Preirradiation of U3Si above the critical temperature for amorphization results in of nanometer-size grains. Subsequent reirradiation below the critical temperature shows that the material has developed a resistance to radiation-induced amorphization higher dose needed to amorphize the preirradiated samples than now preirradiated samples. In the model, it is assumed that grain boundaries act as effective defect sinks, and that enhanced defect annihilation is responsible for retarding amorphization at low temperature. The calculations have been validated against data from ion-irradiation experiments with U3Si. To obtain additional validation, the model has also been applied to the ion-induced motion of the interface between crystalline and amorphous phases of U3Si. Results of this analysis are compared to data and results of calculations for ion bombardment of Si.
