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61.
A novel structure is proposed for doubling the vertical breakdown voltage of silicon-on-insulator(SOI) devices. In this new structure, the conventional buried oxide(BOX) in an SOI device is split into two sections: the source-section BOX and the drain-section BOX. A highly-doped Si layer, referred to as a non-depletion potential-clamped layer(NPCL), is positioned under and close to the two BOX sections. In the split BOXes and the Si region above the BOXes, the blocking voltage(BV) is divided into two parts by the NPCL. The voltage in the NPCL is clamped to be nearly half of the drain voltage. When the drain voltage approaches a breakdown value, the voltage sustained by the source-section BOX and the Si region under the source are nearly the same as the voltage sustained by the drain-section BOX and the Si region under the drain. The vertical BV is therefore almost doubled. The effectiveness of this new structure was verified for a P-channel SOI lateral double-diffused metal-oxide semiconductor(LDMOS) and can be applied to other high-voltage SOI devices. The simulation results show that the BV in an NPCL P-channel SOI LDMOS is improved by 55% and the specific on-resistance(Ron,sp) is reduced by 69% in comparison to the conventional structure. 相似文献
62.
63.
Christoph Scheven Thomas Schmidt 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2018,35(5):1175-1207
We investigate the Dirichlet minimization problem for the total variation and the area functional with a one-sided obstacle. Relying on techniques of convex analysis, we identify certain dual maximization problems for bounded divergence-measure fields, and we establish duality formulas and pointwise relations between (generalized) BV minimizers and dual maximizers. As a particular case, these considerations yield a full characterization of BV minimizers in terms of Euler equations with a measure datum. Notably, our results apply to very general obstacles such as BV obstacles, thin obstacles, and boundary obstacles, and they include information on exceptional sets and up to the boundary. As a side benefit, in some cases we also obtain assertions on the limit behavior of p-Laplace type obstacle problems for .On the technical side, the statements and proofs of our results crucially depend on new versions of Anzellotti type pairings which involve general divergence-measure fields and specific representatives of BV functions. In addition, in the proofs we employ several fine results on (BV) capacities and one-sided approximation. 相似文献
64.
In this paper we consider a new variational model for multiplicative noise removal. We prove the existence and uniqueness of the minimizer for the variational problem. Furthermore, we derive the existence and uniqueness of weak solutions for the associated evolution equation. Finally, some numerical experiments are shown to compare the proposed model with the model given by Aubert and Aujol. 相似文献
65.
A high performance trench insulated gate bipolar transistor which combines a semi-superjunction struc- ture and an accumulation channel (sSJTAC-IGBT) is proposed for the first time. Compared with the TAC-IGBT, the new device not only retains the advantages of the accumulation channel, but also obtains a larger breakdown voltage (BV), a faster turn-off speed and a smaller saturation current level while keeping the on-state voltage drop lower as the TAC-IGBT does as well. Therefore, the new structure enlarges the short circuit safe operating area (SCSOA) and reduces the energy loss during the turn-off process. 相似文献
66.
D.A. Parkes 《Chemical physics letters》1981,77(3):527-532
A continuum-absorption spectrum between 200 and 240 nm is assigned to the acetyl radical. Kinetic measurements using molecular modulation spectroscopy show for the reaction CH3 + CO (+M) → CH3CO + M the rate constants are (1.8 ± 0.2) × 10?18 cm3 molecule?1 s?1 at 100 Torr and (6 ± 1) × 10?18 at 750 Torr. The rate constant for acetyl combination 2CH3CO → (CH3CO)2 is (3.0 ± 10) × 10?11 at 25°C. 相似文献
67.
Luigi Ambrosio 《Set-Valued Analysis》2002,10(2-3):111-128
The aim of this paper is to study the properties of the perimeter measure in the quite general setting of metric measure spaces. In particular, defining the essential boundary *
E of E as the set of points where neither the density of E nor the density of XE is 0, we show that the perimeter measure is concentrated on *
E and is representable by an Hausdorff-type measure. 相似文献
68.
Seung-Yeal Ha 《Journal of Differential Equations》2005,215(1):178-205
We present nonlinear functionals measuring physical space variation and L1-distance between two classical solutions for the Boltzmann equation with a cut-off inverse power potential. In the case that initial datum is a small, smooth perturbation of vacuum and decays fast enough in the phase space, we show that these functionals satisfy stability estimates which lead to BV-type estimates and a uniform L1-stability. 相似文献
69.
The aim of this paper is to discuss the Cauchy problem of the quasilinear hyperbolic equation of the form
ut+x(um)=up 相似文献
70.
In this article, we give a uniform BV estimates and L 1-stability of solutions to the Lax–Friedrichs' scheme for a model of radiating gas when the strict C–F–L (Courant–Friedrichs–Levy) condition is satisfied. This result implies that the approximate solutions generated by the Lax–Friedrichs' scheme converge to the solution given by the method of vanishing viscosity [C. Lattanzio and P. Marcati (2003). Global well-posedness and relaxation limits of a model for radiating gas. Journal of Differential Equations, 190, 439–465]. 相似文献