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We have simulated the technological processes for the well formation in CMOS technology. The general problem of coupled impurities diffusion under oxidizing conditions has been treated by the finite‐element method. The obtained results have been compared to measured profiles. The study of the influence of the technological parameters on the well's structures allowed us to optimize the lateral diffusion, as well as the effects of the field oxidation.

Numerical simulation of the static semiconductor device equations using mixed finite element for the approximation and A.D.I. techniques (Douglas‐Rachford with local time steps) for the solution is presented in this paper. The formulation with electrostatic potential φ and quasi‐Fermi levels φn,φp is used.

A 2D numerical simulation using a finite element technique is presented for computing spreading resistance of a semiconductor buried ridge stripe laser. The simplified physical model is analyzed from the functional analysis point of view and a proof of existence and uniqueness of the nonlinear partial differential equations obtained from this simplified model is given. The discrete associated nonlinear problem is solved on triangular finite elements using conjugate gradient algorithms. Some results are presented for a specific semiconductor laser

Some results related to the algorithmic behaviour in semiconductor devices numerical simulations (‐static case‐), using mixed finite elements and operator splitting techniques have been presented in. The drift‐diffusion model written with the electrostatic potential φ and the quasi‐Fermi levels φn and φp is used.

We present an abstract mathematical and numerical analysis for Drift‐Diffusion equation of heterojunction semiconductor devices with Fermi‐Dirac statistic. For the approximation, a mixed finite element method is considered. This can be profitably used in the investigation of the current through the device structure. A peculiar feature of this mixed formulation is that the electric displacement D and the current densities jn and jp for electrons and holes, are taken as unknowns, together with the potential φ and quas‐Fermi levels φn and φp. This enably D, jn and jp to be determined directly and accurately. For decoupled system, existence, uniqueness, regularity and stability results of the approximate solution are given. A priori and a posteriori error estimates are also presented. A nonlinear implicit scheme with local time steps is used. This algorithm appears to be efficient and gives satisfactory results. Numerical results for an heterojunction bipolar transistor, In two dimension, are presented.

The finite element method is used to solve the non‐linear diffusion equation, taking account of the interaction between impurities due to self‐induced electric field and charged vacancies effects, and of various boundary conditions (evaporation, segregation, oxidation growth…). An incomplete implicit scheme gives the solution of the temporal equation deduced from a quadratic space discretization. The temporal and spatial problems being proved to be quite independent, specific locally refined meshes are developed. The quadratic shape functions allow the use of evolutive mesh for the oxidation simulation without profile degradation. Two realistic industrial steps are described to demonstrate the efficiency of the code.

Recent advances in the fabrication technology of heterojunction semiconductor nanostructures have made possible the realization of systems with extremely small sizes. In these devices, electrons are confined along some directions and are free to move in others. Semiconductor nanostructures have become so small that we have to take into account quantum effects. The two dimensional physical model consists of Poisson’s equation for the electrostatic potential φ, coupled with an eigenvalue problem for Schrödinger’s equation. Proposes

Kite Balloons and Kites 247. Two models of Caquot kite‐balloons. Tests on. Nov. 1916. (3d.).

The design of cantilever pile walls (CPWs) presents several common challenges. These challenges include soil variability, groundwater conditions, complex loading conditions, construction considerations, structural integrity, uncertainties in design parameters and construction and monitoring costs. Accordingly, this paper is to provide a detailed literature review on the design criteria of CPWs, specifically in cohesionless soil. This study aims to present a comprehensive overview of the current state of knowledge in this area.

The paper uses a literature review approach to gather information on the design criteria of CPWs in cohesionless soil. It covers various aspects such as excavation support systems (ESSs), deformation behavior, design criteria, lateral earth pressure calculation theories, load distribution methods and conventional design approaches.

The review identifies and discusses common challenges associated with the design of CPWs in cohesionless soil. It highlights the uncertainties in determining load distribution and the potential for excessive wall deformations. The paper presents various approaches and methodologies proposed by researchers to address these challenges.

The paper contributes to the field of geotechnical engineering by providing a valuable resource for geotechnical engineers and researchers involved in the design and analysis of CPWs in cohesionless soil. It offers insights into the design criteria, challenges and potential solutions specific to CPWs in cohesionless soil, filling a gap in the existing knowledge base. The paper draws attention to the limitations of existing analytical methods that neglect the serviceability limit state and assume rigid plastic soil behavior, highlighting the need for improved design approaches in this context.

A monthly feature giving news of recent Government and professional appointments, industrial changes and business appointments, etc.. The Lord Brabazon of Tara, M.C., P.C., has accepted the Presidency of the College of Aeronautical and Automobile Engineering at Sydney Street, Chelsea.