| 1. |
- Zetterling, Carl-Mikael, et al.
(författare)
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Junction barrier Schottky diodes in 6H SiC
- 1998
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Ingår i: Solid-State Electronics. - 0038-1101 .- 1879-2405. ; 42:9, s. 1757-1759
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Tidskriftsartikel (refereegranskat)abstract
- Junction barrier Schottky (JBS) diodes in 6H SiC have been fabricated and characterised electrically. This device, demonstrated in silicon technology, has the advantage of a low forward voltage drop comparable to that of Schottky diodes, as well as a high blocking voltage and low reverse leakage current of a pn junction. This is especially attractive for wide bandgap materials such as SiC in which pn junctions have a large forward voltage drop. The devices were capable of blocking up to 1100 V with a leakage current density of 0.15 A cm-2, limited by the leakage when the drift region was fully depleted, or breakdown of the SiC material itself. The forward conduction was limited by an on-resistance of 20 mΩ cm2, resulting in forward voltage drops of 2.6 V at 100 A cm-2. © 1998 Published by Elsevier Science Ltd. All rights reserved.
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| 2. |
- Eriksson, Anders, 1953-
(författare)
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Structural instability analyses based on generalised path-following
- 1998
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Ingår i: Computer Methods in Applied Mechanics and Engineering. - 0045-7825 .- 1879-2138. ; 156:1-4, s. 45-74
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes how quasi-static, conservative instability problems can be completely described, using generalised path-following procedures for augmented equilibrium formulations. In particular, methods for treatment of compound critical states are discussed. The numerical methods are seen as extensions to common equilibrium path methods, allowing the solution of subsets of equilibrium states, also fulfilling auxiliary relations, e.g. criticality. These formulations are in general used to describe the parameter dependence in structural response, in instability analyses and in optimisation. The paper describes the general setting of these generalised equilibrium problems, and discusses some details in their numerical treatment. Emphasis is given to the evaluation of path tangent vectors, in the presence of critical eigenvectors for the structural tangential stiffness matrix. Also, the isolation of special states, i.e. vanishing variables, turning points and exchanges of stability, is discussed. Numerical examples are used to show the possibilities and properties of the obtained solution paths, together with some aspects of the numerical procedures.
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| 3. |
- Eriksson, A.
(författare)
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Equilibrium subsets for multi-parametric structural analysis
- 1997
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Ingår i: Computer Methods in Applied Mechanics and Engineering. - 0045-7825 .- 1879-2138. ; 140:3-4, s. 305-327
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Tidskriftsartikel (refereegranskat)abstract
- The paper discusses multi-parametric formulations for structural equilibrium problems. By seeking subsets of equilibrium states, which also fulfil extra conditions, more detailed information on structural behaviour can be obtained. These conditions can be related to analyses of, e.g. critical behaviour, imperfections or optimisation. The paper shows a general problem setting and some interesting augmentations. A solution method for the special case of one-dimensional equilibrium subsets is described. The algorithm is a generalisation of a path-following algorithm, where new methods are developed for the evaluation of the path tangent, and for the isolation of special solution points. Examples are used to show the properties and the possibilities of the ideas.
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| 4. |
- Eriksson, Anders, 1953-, et al.
(författare)
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Numerical analysis of complex instability behaviour using incremental-iterative strategies
- 1999
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Ingår i: Computer Methods in Applied Mechanics and Engineering. - 0045-7825 .- 1879-2138. ; 179:3-4, s. 265-305
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Tidskriftsartikel (refereegranskat)abstract
- The paper describes how quasi-static, conservative instability problems can be analysed in a multi-parametric space, using generalised path-following procedures for augmented equilibrium problems. The general formulation of such augmented equilibrium problems is discussed in some detail. The focus is set on two classes of generalised 1D paths: basic equilibrium paths and fold lines, i.e. critical subset paths. The solution methods are seen as extensions to common incremental-iterative strategies, allowing the computation of subsets of equilibrium states which also fulfil some auxiliary conditions, e.g. criticality. In this context, some emphasis is also given to the evaluation of the properties of the problem, at a certain state; the tangential stiffness is here used to evaluate - possibly multidimensional - tangent spaces, and in the isolation of special states, i.e. vanishing variables, turning points and exchanges of stability, being important aspects of instability analyses. A set of carefully chosen numerical examples demonstrate on one hand the ability of the numerical procedures to deal with complex instability phenomena, including coincident or near coincident buckling modes, modal interaction, secondary bifurcations, and, on the other hand, their versatility in performing parameter sensitivity analyses. Finally, comparisons with alternative techniques, based on asymptotic strategies, are also put forth. © 1999 Elsevier Science S.A.
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