Entries by Graham Bell

How to Achieve Good Parameter Optimization Using The New Methodology in UTMOST III Optimizer

January 1, 2002in /by

Optimization is the task of finding the absolute best set of admissible conditions to achieve your objective, formulated in mathematical terms. The goal of optimization is, given a system, to find the setting of it’s parameters so that to obtain the optimal performance. The performance of the system is given by an evaluation function. Optimization problems are commonly found in a wide range of fields, and it is also of central concern to many problems.

Connectivity Options for DRC Spacing Check Operations in Savage

December 1, 2000in /by

An IC layout has to satisfy many technological design requirements. One of these is spacing, i.e., a layout object has to be separated from another one by some minimal distance. In addition, any spacing requirement (e.g. minimal distance between layout objects) varies depending on the particular features of the layout objects, e.g. the layer the objects belong to, the purpose of these objects, etc.

Optimal Packing of Orthoblocks For ULSI Floorplanning

December 1, 2000in /by

Virtually all latest and prospective enhancements of Expert Layout processor (for example, semi-automatic floorplanning) are based on sophisticated geometrical models. In some cases some advanced mathematical research is necessary to develop efficient algorithms. This article is devoted to the problem of optimal packing of orthoblock which is originated from several areas of VLSI design automation.

Simulating Impurity Freeze-Out During Low Temperature Operation

November 1, 2000in /by

The low temperature operation of many device structures has been shown as an effective method for improving device performance without reducing device size. By modeling low temperature phenomena, numerical simulation of device operation at low temperatures provides an effective means for analyzing such performance improvements before investing manufacturing time or money. It is the purpose of this paper to discuss the modeling of the dopant freeze-out phenomenon in ATLAS and provide an application example of its use.

Simulation of Vertical Double-Gate SOI MOSFETs Using Device3D

November 1, 2000in /by

This article will present the simulation methodology of a self-aligned double-gate MOSFET structure (FinFET) using SILVACO 3-D simulation suite. The double-gate MOSFET is one of the most attractive alternative to classical MOSFET structure for gate length down to 20nm. The main advantage of the FinFET is the ability to drastically reduce the short channel effect. In spite of his double-gate structure, the FinFET is closed to its root, the conventional MOSFET in layout and fabrication. 3-D numerical simulations of the FinFET are performed in this article, in order to validate the basic principles and to uncover several important aspects: evaluation of the length , width and quantum effects.

Non-Stationary Transport Effects: Impact on Performances of Realistic 50nm MOSFET Technology

November 1, 2000in /by

We analyze quantitatively the real impact of technology on the needed level for carrier transport modeling. The results, based on theoretical analyzes, are applied to existing devices. This work shows which recipes must be used to evaluate the performances of advanced device architectures (down to 50nm gate length). An original point of this work is the investigation of technology influence (channel doping and LDD doping) on injection velocity at source side and on drain current. The results open the perspective of specific engineering of access regions in order to take full advantage of non-stationary effects on the drain current.