Defects in SiC Single Crystals and Their Influence on Device Performance PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Defects in SiC Single Crystals and Their Influence on Device Performance PDF full book. Access full book title Defects in SiC Single Crystals and Their Influence on Device Performance by . Download full books in PDF and EPUB format.
Author: Publisher: ISBN: Category : Languages : en Pages : 0
Book Description
This project constituted an extensive program of research aimed at applying the techniques of Synchrotron White Beam X-ray Topography (SWBXT), Nomarski Optical Microscopy, Stereo Transmission Optical Microscopy and Scanning Electron Microscopy to the detailed analysis of defect structures in SiC crystals of various polytypes, and to determine how these defect structures can influence the performance of various kinds of device manufactured therein. It has served to establish a heightened awareness of the importance of a detailed understanding of growth defect microstructure to the future of SiC technology. Results obtained in this project have helped prioritize SiC crystal quality improvements. Two kinds of defect have been identified in 6H and 4H-SiC, basal plane dislocations, and dislocations with mostly screw component lying either at a small angle, or parallel, to the c-axis, with screw component of Burgers vector being equal to nc, where c is the lattice parameter. In 6H, dislocations with b greater than or equal 2c have hollow cores, the diameters of which conform to the theory of F.C. Frank. The same is true for dislocations in 4H with b greater than equal 3c. Preliminary results show that all such dislocations (from n=1 to n>8) can modify the I-V characteristics of diodes, giving rise to higher leakage currents and premature breakdown point-failures.
Author: Publisher: ISBN: Category : Languages : en Pages : 0
Book Description
This project constituted an extensive program of research aimed at applying the techniques of Synchrotron White Beam X-ray Topography (SWBXT), Nomarski Optical Microscopy, Stereo Transmission Optical Microscopy and Scanning Electron Microscopy to the detailed analysis of defect structures in SiC crystals of various polytypes, and to determine how these defect structures can influence the performance of various kinds of device manufactured therein. It has served to establish a heightened awareness of the importance of a detailed understanding of growth defect microstructure to the future of SiC technology. Results obtained in this project have helped prioritize SiC crystal quality improvements. Two kinds of defect have been identified in 6H and 4H-SiC, basal plane dislocations, and dislocations with mostly screw component lying either at a small angle, or parallel, to the c-axis, with screw component of Burgers vector being equal to nc, where c is the lattice parameter. In 6H, dislocations with b greater than or equal 2c have hollow cores, the diameters of which conform to the theory of F.C. Frank. The same is true for dislocations in 4H with b greater than equal 3c. Preliminary results show that all such dislocations (from n=1 to n>8) can modify the I-V characteristics of diodes, giving rise to higher leakage currents and premature breakdown point-failures.
Author: Publisher: ISBN: Category : Languages : en Pages : 9
Book Description
Structural perfection of silicon carbide (SiC) single crystals is essential to achieve high-performance power devices. A new bulk growth process for SiC proposed by researchers at NASA Glenn Research Center, called large tapered crystal (LTC) growth, based on axial fiber growth followed by lateral expansion, could produce SiC boules with potentially as few as one threading screw dislocation per wafer. In this study, the lateral expansion aspect of LTC growth is addressed through analysis of lateral growth of 6H-SiC a/m-plane seed crystals by hot-wall chemical vapor deposition. Preliminary synchrotron white-beam x-ray topography (SWBXT) indicates that the as-grown boules match the polytype structure of the underlying seed and have a faceted hexagonal morphology with a strain-free surface marked by steps. SWBXT Laue diffraction patterns of transverse and axial slices of the boules reveal streaks suggesting the existence of stacking faults/polytypes, and this is confirmed by micro-Raman spectroscopy. Transmission x-ray topography of both transverse and axial slices reveals inhomogeneous strains at the seed-epilayer interface and linear features propagating from the seed along the growth direction. Micro-Raman mapping of an axial slice reveals that the seed contains high stacking disorder, while contrast extinction analysis (g·b and g·b×l) of the linear features reveals that these are mostly edge-type basal plane dislocations. Further high-resolution transmission electron microscopy investigation of the seed-homoepilayer interface also reveals nanobands of different SiC polytypes. A model for their formation mechanism is proposed. Lastly, the implication of these results for improving the LTC growth process is addressed.
Author: S. Ashok Publisher: ISBN: Category : Technology & Engineering Languages : en Pages : 522
Book Description
This book focuses on the deliberate introduction and manipulation of defects and impurities in order to engineer desired properties in semiconductor materials and devices. In view of current exciting developments in wide-bandgap semiconductors like GaN for blue light emission, as well as high-speed and high-temperature electronics, dopant and defect issues relevant to these materials are addressed. Also featured are semiconductor nanocavities and nano-structures, with emphasis on the formation and impact of vacancy-type defects. Defect reaction problems pertaining to impurity gettering, precipitation and hydrogen passivation are specific examples of defect engineering that improve the electronic quality of the material. A number of papers also deal with characterization techniques needed to study and to identify defects in materials and device structures. Finally, papers also address issues such as interface control and passivation, application of ion implantation, plasma treatment and rapid thermal processing for creating/activating/suppressing trap levels, and device applications.
Author: A.A. Lebedev Publisher: Materials Research Forum LLC ISBN: 1945291117 Category : Technology & Engineering Languages : en Pages : 172
Book Description
The book reviews the most interesting research concerning the radiation defects formed in 6H-, 4H-, and 3C-SiC under irradiation with electrons, neutrons, and some kinds of ions. The electrical parameters that make SiC a promising material for applications in modern electronics are discussed in detail. Specific features of the crystal structure of SiC are considered. It is shown that, when wide-bandgap semiconductors are studied, it is necessary to take into account the temperature dependence of the carrier removal rate, which is a standard parameter for determining the radiation hardness of semiconductors. The carrier removal rate values obtained by irradiation of various SiC polytypes with n- and p-type conductivity are analyzed in relation to the type and energy of the irradiating particles. The influence exerted by the energy of charged particles on how radiation defects are formed and conductivity is compensated in semiconductors under irradiation is analyzed. Furthermore, the possibility to produce controlled transformation of silicon carbide polytype is considered. The involvement of radiation defects in radiative and nonradiative recombination processes in SiC is analyzed. Data are also presented regarding the degradation of particular SiC electronic devices under the influence of radiation and a conclusion is made regarding the radiation resistance of SiC. Lastly, the radiation hardness of devices based on silicon and silicon carbide are compared.
Author: Peter Friedrichs Publisher: John Wiley & Sons ISBN: 3527629068 Category : Science Languages : en Pages : 528
Book Description
This book prestigiously covers our current understanding of SiC as a semiconductor material in electronics. Its physical properties make it more promising for high-powered devices than silicon. The volume is devoted to the material and covers methods of epitaxial and bulk growth. Identification and characterization of defects is discussed in detail. The contributions help the reader to develop a deeper understanding of defects by combining theoretical and experimental approaches. Apart from applications in power electronics, sensors, and NEMS, SiC has recently gained new interest as a substrate material for the manufacture of controlled graphene. SiC and graphene research is oriented towards end markets and has high impact on areas of rapidly growing interest like electric vehicles. The list of contributors reads like a "Who's Who" of the SiC community, strongly benefiting from collaborations between research institutions and enterprises active in SiC crystal growth and device development.
Author: 
Author: 
Author: 
Author: 
Author: S. Ashok
Author: K. Shenai
Author: W. Dietze
Author: A.A. Lebedev
Author: 
Author: K. N. Bhat
Author: Peter Friedrichs