Author: S. Pizzini
Publisher: Materials Research Forum LLC
ISBN: 1945291230
Category : Technology & Engineering
Languages : en
Pages : 134
Book Description
A self-consistent model of point defects requires a reliable connection with the experimentally deduced structural, spectroscopic and thermodynamic properties of the defect centres, to allow their unambiguous identification. This book focuses on the properties of defects in group IV semiconductors and seeks to clarify whether full knowledge of their chemical nature can account for several problems encountered in practice. It is shown how difficult the fulfilment of self-consistency conditions can be, even today, after more than four decades of dedicated research work, especially in the case of compound semiconductors, such as SiC, but also in the apparently simple cases of silicon and germanium. The reason for this is that the available microscopic models do not yet account for defect interactions in real solids.
Point Defects in Group IV Semiconductors
Author: S. Pizzini
Publisher: Materials Research Forum LLC
ISBN: 1945291230
Category : Technology & Engineering
Languages : en
Pages : 134
Book Description
A self-consistent model of point defects requires a reliable connection with the experimentally deduced structural, spectroscopic and thermodynamic properties of the defect centres, to allow their unambiguous identification. This book focuses on the properties of defects in group IV semiconductors and seeks to clarify whether full knowledge of their chemical nature can account for several problems encountered in practice. It is shown how difficult the fulfilment of self-consistency conditions can be, even today, after more than four decades of dedicated research work, especially in the case of compound semiconductors, such as SiC, but also in the apparently simple cases of silicon and germanium. The reason for this is that the available microscopic models do not yet account for defect interactions in real solids.
Publisher: Materials Research Forum LLC
ISBN: 1945291230
Category : Technology & Engineering
Languages : en
Pages : 134
Book Description
A self-consistent model of point defects requires a reliable connection with the experimentally deduced structural, spectroscopic and thermodynamic properties of the defect centres, to allow their unambiguous identification. This book focuses on the properties of defects in group IV semiconductors and seeks to clarify whether full knowledge of their chemical nature can account for several problems encountered in practice. It is shown how difficult the fulfilment of self-consistency conditions can be, even today, after more than four decades of dedicated research work, especially in the case of compound semiconductors, such as SiC, but also in the apparently simple cases of silicon and germanium. The reason for this is that the available microscopic models do not yet account for defect interactions in real solids.
Defects in Semiconductors
Author:
Publisher: Academic Press
ISBN: 0128019409
Category : Technology & Engineering
Languages : en
Pages : 458
Book Description
This volume, number 91 in the Semiconductor and Semimetals series, focuses on defects in semiconductors. Defects in semiconductors help to explain several phenomena, from diffusion to getter, and to draw theories on materials' behavior in response to electrical or mechanical fields. The volume includes chapters focusing specifically on electron and proton irradiation of silicon, point defects in zinc oxide and gallium nitride, ion implantation defects and shallow junctions in silicon and germanium, and much more. It will help support students and scientists in their experimental and theoretical paths. - Expert contributors - Reviews of the most important recent literature - Clear illustrations - A broad view, including examination of defects in different semiconductors
Publisher: Academic Press
ISBN: 0128019409
Category : Technology & Engineering
Languages : en
Pages : 458
Book Description
This volume, number 91 in the Semiconductor and Semimetals series, focuses on defects in semiconductors. Defects in semiconductors help to explain several phenomena, from diffusion to getter, and to draw theories on materials' behavior in response to electrical or mechanical fields. The volume includes chapters focusing specifically on electron and proton irradiation of silicon, point defects in zinc oxide and gallium nitride, ion implantation defects and shallow junctions in silicon and germanium, and much more. It will help support students and scientists in their experimental and theoretical paths. - Expert contributors - Reviews of the most important recent literature - Clear illustrations - A broad view, including examination of defects in different semiconductors
Charged Semiconductor Defects
Author: Edmund G. Seebauer
Publisher: Springer Science & Business Media
ISBN: 1848820593
Category : Science
Languages : en
Pages : 304
Book Description
Defects in semiconductors have been studied for many years, in many cases with a view toward controlling their behaviour through various forms of “defect engineering”. For example, in the bulk, charging significantly affects the total concentration of defects that are available to mediate phenomena such as solid-state diffusion. Surface defects play an important role in mediating surface mass transport during high temperature processing steps such as epitaxial film deposition, diffusional smoothing in reflow, and nanostructure formation in memory device fabrication. “Charged Defects in Semiconductors” details the current state of knowledge regarding the properties of the ionized defects that can affect the behaviour of advanced transistors, photo-active devices, catalysts, and sensors. Features: group IV, III-V, and oxide semiconductors; intrinsic and extrinsic defects; and, point defects, as well as defect pairs, complexes and clusters.
Publisher: Springer Science & Business Media
ISBN: 1848820593
Category : Science
Languages : en
Pages : 304
Book Description
Defects in semiconductors have been studied for many years, in many cases with a view toward controlling their behaviour through various forms of “defect engineering”. For example, in the bulk, charging significantly affects the total concentration of defects that are available to mediate phenomena such as solid-state diffusion. Surface defects play an important role in mediating surface mass transport during high temperature processing steps such as epitaxial film deposition, diffusional smoothing in reflow, and nanostructure formation in memory device fabrication. “Charged Defects in Semiconductors” details the current state of knowledge regarding the properties of the ionized defects that can affect the behaviour of advanced transistors, photo-active devices, catalysts, and sensors. Features: group IV, III-V, and oxide semiconductors; intrinsic and extrinsic defects; and, point defects, as well as defect pairs, complexes and clusters.
Miniaturized Silicon Photodetectors
Author: Maurizio Casalino
Publisher: MDPI
ISBN: 3036500448
Category : Technology & Engineering
Languages : en
Pages : 148
Book Description
Silicon (Si) technologies provide an excellent platform for the design of microsystems where photonic and microelectronic functionalities are monolithically integrated on the same substrate. In recent years, a variety of passive and active Si photonic devices have been developed, and among them, photodetectors have attracted particular interest from the scientific community. Si photodiodes are typically designed to operate at visible wavelengths, but, unfortunately, their employment in the infrared (IR) range is limited due to the neglectable Si absorption over 1100 nm, even though the use of germanium (Ge) grown on Si has historically allowed operations to be extended up to 1550 nm. In recent years, significant progress has been achieved both by improving the performance of Si-based photodetectors in the visible range and by extending their operation to infrared wavelengths. Near-infrared (NIR) SiGe photodetectors have been demonstrated to have a “zero change” CMOS process flow, while the investigation of new effects and structures has shown that an all-Si approach could be a viable option to construct devices comparable with Ge technology. In addition, the capability to integrate new emerging 2D and 3D materials with Si, together with the capability of manufacturing devices at the nanometric scale, has led to the development of new device families with unexpected performance. Accordingly, this Special Issue of Micromachines seeks to showcase research papers, short communications, and review articles that show the most recent advances in the field of silicon photodetectors and their respective applications.
Publisher: MDPI
ISBN: 3036500448
Category : Technology & Engineering
Languages : en
Pages : 148
Book Description
Silicon (Si) technologies provide an excellent platform for the design of microsystems where photonic and microelectronic functionalities are monolithically integrated on the same substrate. In recent years, a variety of passive and active Si photonic devices have been developed, and among them, photodetectors have attracted particular interest from the scientific community. Si photodiodes are typically designed to operate at visible wavelengths, but, unfortunately, their employment in the infrared (IR) range is limited due to the neglectable Si absorption over 1100 nm, even though the use of germanium (Ge) grown on Si has historically allowed operations to be extended up to 1550 nm. In recent years, significant progress has been achieved both by improving the performance of Si-based photodetectors in the visible range and by extending their operation to infrared wavelengths. Near-infrared (NIR) SiGe photodetectors have been demonstrated to have a “zero change” CMOS process flow, while the investigation of new effects and structures has shown that an all-Si approach could be a viable option to construct devices comparable with Ge technology. In addition, the capability to integrate new emerging 2D and 3D materials with Si, together with the capability of manufacturing devices at the nanometric scale, has led to the development of new device families with unexpected performance. Accordingly, this Special Issue of Micromachines seeks to showcase research papers, short communications, and review articles that show the most recent advances in the field of silicon photodetectors and their respective applications.
Point Defects in Semiconductors I
Author: M. Lannoo
Publisher: Springer Science & Business Media
ISBN: 364281574X
Category : Science
Languages : en
Pages : 283
Book Description
From its early beginning before the war, the field of semiconductors has developped as a classical example where the standard approximations of 'band theory' can be safely used to study its interesting electronic properties. Thus in these covalent crystals, the electronic structure is only weakly coupled with the atomic vibrations; one-electron Bloch functions can be used and their energy bands can be accurately computed in the neighborhood of the energy gap between the valence and conduction bands; nand p doping can be obtained by introducing substitutional impurities which only introduce shallow donors and acceptors and can be studied by an effective-mass weak-scattering description. Yet, even at the beginning, it was known from luminescence studies that these simple concepts failed to describe the various 'deep levels' introduced near the middle of the energy gap by strong localized imperfections. These imperfections not only include some interstitial and many substitutional atoms, but also 'broken bonds' associated with surfaces and interfaces, dis location cores and 'vacancies', i.e., vacant iattice sites in the crystal. In all these cases, the electronic structure can be strongly correlated with the details of the atomic structure and the atomic motion. Because these 'deep levels' are strongly localised, electron-electron correlations can also playa significant role, and any weak perturbation treatment from the perfect crystal structure obviously fails. Thus, approximate 'strong coupling' techniques must often be used, in line' with a more chemical de scription of bonding.
Publisher: Springer Science & Business Media
ISBN: 364281574X
Category : Science
Languages : en
Pages : 283
Book Description
From its early beginning before the war, the field of semiconductors has developped as a classical example where the standard approximations of 'band theory' can be safely used to study its interesting electronic properties. Thus in these covalent crystals, the electronic structure is only weakly coupled with the atomic vibrations; one-electron Bloch functions can be used and their energy bands can be accurately computed in the neighborhood of the energy gap between the valence and conduction bands; nand p doping can be obtained by introducing substitutional impurities which only introduce shallow donors and acceptors and can be studied by an effective-mass weak-scattering description. Yet, even at the beginning, it was known from luminescence studies that these simple concepts failed to describe the various 'deep levels' introduced near the middle of the energy gap by strong localized imperfections. These imperfections not only include some interstitial and many substitutional atoms, but also 'broken bonds' associated with surfaces and interfaces, dis location cores and 'vacancies', i.e., vacant iattice sites in the crystal. In all these cases, the electronic structure can be strongly correlated with the details of the atomic structure and the atomic motion. Because these 'deep levels' are strongly localised, electron-electron correlations can also playa significant role, and any weak perturbation treatment from the perfect crystal structure obviously fails. Thus, approximate 'strong coupling' techniques must often be used, in line' with a more chemical de scription of bonding.
Point Defects in Semiconductors and Insulators
Author: Johann-Martin Spaeth
Publisher: Springer Science & Business Media
ISBN: 9783540426950
Category : Technology & Engineering
Languages : en
Pages : 508
Book Description
The precedent book with the title "Structural Analysis of Point Defects in Solids: An introduction to multiple magnetic resonance spectroscopy" ap peared about 10 years ago. Since then a very active development has oc curred both with respect to the experimental methods and the theoretical interpretation of the experimental results. It would therefore not have been sufficient to simply publish a second edition of the precedent book with cor rections and a few additions. Furthermore the application of the multiple magnetic resonance methods has more and more shifted towards materials science and represents one of the important methods of materials analysis. Multiple magnetic resonances are used less now for "fundamental" studies in solid state physics. Therefore a more "pedestrian" access to the meth ods is called for to help the materials scientist to use them or to appreciate results obtained by using these methods. We have kept the two introduc tory chapters on conventional electron paramagnetic resonance (EPR) of the precedent book which are the base for the multiple resonance methods. The chapter on optical detection of EPR (ODEPR) was supplemented by sections on the structural information one can get from "forbidden" transitions as well as on spatial correlations between defects in the so-called "cross relaxation spectroscopy". High-field ODEPR/ENDOR was also added. The chapter on stationary electron nuclear double resonance (ENDOR) was supplemented by the method of stochastic END OR developed a few years ago in Paderborn which is now also commercially available.
Publisher: Springer Science & Business Media
ISBN: 9783540426950
Category : Technology & Engineering
Languages : en
Pages : 508
Book Description
The precedent book with the title "Structural Analysis of Point Defects in Solids: An introduction to multiple magnetic resonance spectroscopy" ap peared about 10 years ago. Since then a very active development has oc curred both with respect to the experimental methods and the theoretical interpretation of the experimental results. It would therefore not have been sufficient to simply publish a second edition of the precedent book with cor rections and a few additions. Furthermore the application of the multiple magnetic resonance methods has more and more shifted towards materials science and represents one of the important methods of materials analysis. Multiple magnetic resonances are used less now for "fundamental" studies in solid state physics. Therefore a more "pedestrian" access to the meth ods is called for to help the materials scientist to use them or to appreciate results obtained by using these methods. We have kept the two introduc tory chapters on conventional electron paramagnetic resonance (EPR) of the precedent book which are the base for the multiple resonance methods. The chapter on optical detection of EPR (ODEPR) was supplemented by sections on the structural information one can get from "forbidden" transitions as well as on spatial correlations between defects in the so-called "cross relaxation spectroscopy". High-field ODEPR/ENDOR was also added. The chapter on stationary electron nuclear double resonance (ENDOR) was supplemented by the method of stochastic END OR developed a few years ago in Paderborn which is now also commercially available.
Chemistry of Semiconductors
Author: Sergio Pizzini
Publisher: Royal Society of Chemistry
ISBN: 1839162120
Category : Science
Languages : en
Pages : 375
Book Description
Publisher: Royal Society of Chemistry
ISBN: 1839162120
Category : Science
Languages : en
Pages : 375
Book Description
Defects in Nanocrystals
Author: Sergio Pizzini
Publisher: CRC Press
ISBN: 1000066150
Category : Technology & Engineering
Languages : en
Pages : 253
Book Description
Defects in Nanocrystals: Structural and Physico-Chemical Aspects discusses the nature of semiconductor systems and the effect of the size and shape on their thermodynamic and optoelectronic properties at the mesoscopic and nanoscopic levels. The nanostructures considered in this book are individual nanometric crystallites, nanocrystalline films, and nanowires of which the thermodynamic, structural, and optical properties are discussed in detail. The work: Outlines the influence of growth processes on their morphology and structure Describes the benefits of optical spectroscopies in the understanding of the role and nature of defects in nanostructured semiconductors Considers the limits of nanothermodynamics Details the critical role of interfaces in nanostructural behavior Covers the importance of embedding media in the physico-chemical properties of nanostructured semiconductors Explains the negligible role of core point defects vs. surface and interface defects Written for researchers, engineers, and those working in the physical and physicochemical sciences, this work comprehensively details the chemical, structural, and optical properties of semiconductor nanostructures for the development of more powerful and efficient devices.
Publisher: CRC Press
ISBN: 1000066150
Category : Technology & Engineering
Languages : en
Pages : 253
Book Description
Defects in Nanocrystals: Structural and Physico-Chemical Aspects discusses the nature of semiconductor systems and the effect of the size and shape on their thermodynamic and optoelectronic properties at the mesoscopic and nanoscopic levels. The nanostructures considered in this book are individual nanometric crystallites, nanocrystalline films, and nanowires of which the thermodynamic, structural, and optical properties are discussed in detail. The work: Outlines the influence of growth processes on their morphology and structure Describes the benefits of optical spectroscopies in the understanding of the role and nature of defects in nanostructured semiconductors Considers the limits of nanothermodynamics Details the critical role of interfaces in nanostructural behavior Covers the importance of embedding media in the physico-chemical properties of nanostructured semiconductors Explains the negligible role of core point defects vs. surface and interface defects Written for researchers, engineers, and those working in the physical and physicochemical sciences, this work comprehensively details the chemical, structural, and optical properties of semiconductor nanostructures for the development of more powerful and efficient devices.
Color Centers in Semiconductors for Quantum Applications
Author: Joel Davidsson
Publisher: Linköping University Electronic Press
ISBN: 9179297307
Category : Electronic books
Languages : en
Pages : 72
Book Description
Point defects in semiconductors have been and will continue to be relevant for applications. Shallow defects realize transistors, which power the modern age of information, and in the not-too-distant future, deep-level defects could provide the foundation for a revolution in quantum information processing. Deep-level defects (in particular color centers) are also of interest for other applications such as a single photon emitter, especially one that emits at 1550 nm, which is the optimal frequency for long-range communication via fiber optics. First-principle calculations can predict the energies and optical properties of point defects. I performed extensive convergence tests for magneto-optical properties, such as zero phonon lines, hyperfine coupling parameters, and zero-field splitting for the four different configurations of the divacancy in 4H-SiC. Comparing the converged results with experimental measurements, a clear identification of the different configurations was made. With this approach, I also identified all configurations for the silicon vacancy in 4H-SiC as well as the divacancy and silicon vacancy in 6H-SiC. The same method was further used to identify two additional configurations belonging to the divacancy present in a 3C stacking fault inclusion in 4H-SiC. I extended the calculated properties to include the transition dipole moment which provides the polarization, intensity, and lifetime of the zero phonon lines. When calculating the transition dipole moment, I show that it is crucial to include the self-consistent change of the electronic orbitals in the excited state due to the geometry relaxation. I tested the method on the divacancy in 4H-SiC, further strengthening the previous identification and providing accurate photoluminescence intensities and lifetimes. Finding stable point defects with the right properties for a given application is a challenging task. Due to the vast number of possible point defects present in bulk semiconductor materials, I designed and implemented a collection of automatic workflows to systematically investigate any point defects. This collection is called ADAQ (Automatic Defect Analysis and Qualification) and automates every step of the theoretical process, from creating defects to predicting their properties. Using ADAQ, I screened about 8000 intrinsic point defect clusters in 4H-SiC. This thesis presents an overview of the formation energy and the most relevant optical properties for these single and double point defects. These results show great promise for finding new color centers suitable for various quantum applications.
Publisher: Linköping University Electronic Press
ISBN: 9179297307
Category : Electronic books
Languages : en
Pages : 72
Book Description
Point defects in semiconductors have been and will continue to be relevant for applications. Shallow defects realize transistors, which power the modern age of information, and in the not-too-distant future, deep-level defects could provide the foundation for a revolution in quantum information processing. Deep-level defects (in particular color centers) are also of interest for other applications such as a single photon emitter, especially one that emits at 1550 nm, which is the optimal frequency for long-range communication via fiber optics. First-principle calculations can predict the energies and optical properties of point defects. I performed extensive convergence tests for magneto-optical properties, such as zero phonon lines, hyperfine coupling parameters, and zero-field splitting for the four different configurations of the divacancy in 4H-SiC. Comparing the converged results with experimental measurements, a clear identification of the different configurations was made. With this approach, I also identified all configurations for the silicon vacancy in 4H-SiC as well as the divacancy and silicon vacancy in 6H-SiC. The same method was further used to identify two additional configurations belonging to the divacancy present in a 3C stacking fault inclusion in 4H-SiC. I extended the calculated properties to include the transition dipole moment which provides the polarization, intensity, and lifetime of the zero phonon lines. When calculating the transition dipole moment, I show that it is crucial to include the self-consistent change of the electronic orbitals in the excited state due to the geometry relaxation. I tested the method on the divacancy in 4H-SiC, further strengthening the previous identification and providing accurate photoluminescence intensities and lifetimes. Finding stable point defects with the right properties for a given application is a challenging task. Due to the vast number of possible point defects present in bulk semiconductor materials, I designed and implemented a collection of automatic workflows to systematically investigate any point defects. This collection is called ADAQ (Automatic Defect Analysis and Qualification) and automates every step of the theoretical process, from creating defects to predicting their properties. Using ADAQ, I screened about 8000 intrinsic point defect clusters in 4H-SiC. This thesis presents an overview of the formation energy and the most relevant optical properties for these single and double point defects. These results show great promise for finding new color centers suitable for various quantum applications.
Silicon, Germanium, and Their Alloys
Author: Gudrun Kissinger
Publisher: CRC Press
ISBN: 1466586648
Category : Science
Languages : en
Pages : 436
Book Description
Despite the vast knowledge accumulated on silicon, germanium, and their alloys, these materials still demand research, eminently in view of the improvement of knowledge on silicon–germanium alloys and the potentialities of silicon as a substrate for high-efficiency solar cells and for compound semiconductors and the ongoing development of nanodevices based on nanowires and nanodots. Silicon, Germanium, and Their Alloys: Growth, Defects, Impurities, and Nanocrystals covers the entire spectrum of R&D activities in silicon, germanium, and their alloys, presenting the latest achievements in the field of crystal growth, point defects, extended defects, and impurities of silicon and germanium nanocrystals. World-recognized experts are the authors of the book’s chapters, which span bulk, thin film, and nanostructured materials growth and characterization problems, theoretical modeling, crystal defects, diffusion, and issues of key applicative value, including chemical etching as a defect delineation technique, the spectroscopic analysis of impurities, and the use of devices as tools for the measurement of materials quality.
Publisher: CRC Press
ISBN: 1466586648
Category : Science
Languages : en
Pages : 436
Book Description
Despite the vast knowledge accumulated on silicon, germanium, and their alloys, these materials still demand research, eminently in view of the improvement of knowledge on silicon–germanium alloys and the potentialities of silicon as a substrate for high-efficiency solar cells and for compound semiconductors and the ongoing development of nanodevices based on nanowires and nanodots. Silicon, Germanium, and Their Alloys: Growth, Defects, Impurities, and Nanocrystals covers the entire spectrum of R&D activities in silicon, germanium, and their alloys, presenting the latest achievements in the field of crystal growth, point defects, extended defects, and impurities of silicon and germanium nanocrystals. World-recognized experts are the authors of the book’s chapters, which span bulk, thin film, and nanostructured materials growth and characterization problems, theoretical modeling, crystal defects, diffusion, and issues of key applicative value, including chemical etching as a defect delineation technique, the spectroscopic analysis of impurities, and the use of devices as tools for the measurement of materials quality.