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Next: 1.1 ECAD - Electronic Computer-Aided Design Up: PhD Thesis Rui Martins Previous: List of Abbreviations


1. Introduction

Almost at the end of the second millennium we experience what has been called the information revolution. This was made possible because Very Large Scale Integration (VLSI) technology gave man, for the first time, a huge computing and reasoning power. It all started in 1947 when John Bardeen, Walter Brattain and William Shockely invented the bipolar transistor. A decade later Jack Kilby of Texas Instruments achieved a major breakthrough when he created the first Integrated Circuit (IC), which was then improved by Robert Noyce and Gordon Moore of Fairchild Semiconductor with the development of the planar transistor. Since this latter invention the microelectronic industry has been growing exponentially, in close agreement with the doubling of component (and functional) density every 1.5 years and of the maximum circuit speed every 2 years, as Gordon Moore early noted [1]. Albeit integrated circuit miniaturization is always associated with some sort of new unwanted phenomena, these have always been successfully solved in the past and is expected to happen in the future. This is what our work is about - The design of CAD tools capable of handling the problems that modern integrated circuits face and will face.

Everyday more and more applications for integrated circuits are discovered, some of them for use in trivial objects of our quotidian lives, such as automobiles, telephones, or a simple toaster. The objective is to replace the complexity (and cost) of the electronics in such systems by an integrated circuit, aiming the system on chip as ultimate target. But the huge density of modern integrated circuits brings about several new problems in both manufacture and design areas. From these the power dissipation and in-chip interconnections are considered to be of paramount relevance [2][3]. The power dissipation (which below a density level of $10^6$ transistors/cm$^2$ was never of crucial importance) is expected to be the main limitation of high performance integrated circuits by the year 2012 [2][4]. Besides, power consumption is also of considerable importance in the very fast growing market of the portable equipment, where despite some improvements in batteries, there is still a lack of good power supplies. In the near future interconnections are expected to be responsible for a large part of the chip area and to constitute a severe limitation in maximum circuit's speed [3][5]. Due to the extremely high budgets required for fabrication facilities and equipment, the development strategies based on experimental work are becoming impracticable, forcing the semiconductor industry to rely, to a large extend, on Computer-Aided Design (CAD) methodologies. In addition to the well-established and extensively used Electronic CAD (ECAD), Technology CAD (TCAD) tools are indispensable in the development of future generations of fabrication processes [6]. ECAD is concerned with the design of an integrated circuit in terms of behavioral descriptions, netlists, schematics and layout. It can model the integrated circuit as a whole or as a set of functional blocks. TCAD tools have been developed to simulate the several fabrication process steps and to characterize the resultant devices% latex2html id marker 7967
\setcounter{footnote}{1}\fnsymbol{footnote}% latex2html id marker 7967
ootnote}{1}42#1</SUP></A> prior to actual fabrication. Usually only a reduced number
of devices can be analyzed at once, although they can be used to
create higher-level models employed by ECAD circuit simulators, provided
an interface between ECAD and TCAD exists. 

<P>
In the following sections an overview of ECAD and TCAD roles is
presented. Then, the introduction closes with a short description of
the TCAD environment used in this work and the outline of the thesis.

<P>
<BR><HR><H4>Footnotes</H4>
<DL>
<DT><A NAME=... devices% latex2html id marker 7967
\setcounter{footnote}{1}\fnsymbol{footnote}% latex2html id marker 7967
ootnote}{1}42#1</SUP></A>
<DD>Devices, in this context, are not
restricted to active devices. They can represent, for example, resistors or even
parasitic capacitors.

</DL>
<BR> <HR>
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<A NAME=


next up previous
Next: 1.1 ECAD - Electronic Computer-Aided Design Up: PhD Thesis Rui Martins Previous: List of Abbreviations
Rui Martins
1999-02-24