1. Introduction

Semiconductor technology and industry has enormously advanced in the past decades. Starting from a plastic triangle, a slab of germanium, some gold foil and gold contacts (the first bipolar transistor in 1947), as of 2004 the typical transistor density per circuit is around 140 million transistors/$cm^2$ for MPU (micro processor unit) applications, doubling every year (Moore's Law [2]). This trend is shown in Figure 1.1 starting with the 4040, the first Intel Processor in 1971.

Figure 1.1: Intel MPU transistor density trend starting with the 4040 processor [3]. The dashed line shows the ITRS chip size model [4]

Semiconductor Industry is the main driving force for technology innovation and ``New Economy'' markets. The ongoing development of faster integrated circuits with higher device density has led to highly complex and sophisticated products which are widely accepted by society. A modern integrated circuit cannot be developed without the massive use of computer aided design (CAD) in any step of the complex flow from the idea to the final product. This work concentrates on technology computer aided design (TCAD) [5] and its integration into the semiconductor fabrication process flow. The use of TCAD is twofold: Firstly it models the complex flow of semiconductor fabrication steps ending up with detailed information on geometric shape and doping profile distribution of a semiconductor device in scope (like CMOS- or Bipolar-Transistors) $\Rightarrow$ Process TCAD-Simulation. Secondly it uses the information of the first step to predict the device characteristics of semiconductor devices leading to circuit simulation models as implemented in any circuit simulator like PSPICE [6], ELDO [7], SPECTRE [8] etc. $\Rightarrow$ Device TCAD-Simulation. The setup of such a simulation methodology requires an almost completely documented semiconductor fabrication process flow including such fabrication details like angle of incidence of ions implanted in ion implantation process steps, or etch rate distribution as a function of the local angle of the etched layer surface. Any modern semiconductor fabrication facility maintains such documentation to an extremely high detail level, but commercial TCAD simulation software like Synopsys [9] or Silvaco [10] Tools need this information in a very specialized format [11] which cannot be directly deduced from the standard process flow documentation. The traditional way of setting up the process- and to some extent also the device TCAD-simulation framework is, entering it by hand, which is of course a source of numerous errors. This work proposes a new methodology with the main target to automate this conversion process to a high extent.

Chapter 2 describes the overall chain of processes, how integrated circuits are fabricated. An overview with respect to the related simulator tools is given.

Chapter 3 concentrates on the detailed simulation methodologies to model the IC (Integrated Circuit) fabrication.

Chapter 4 identifies the interfaces between the fabrication process and simulation. It outlines the detailed structure of the interfaces. A comprehensive overview over the interactions in this integrated system is given as well.

Chapter 5 provides the detailed description of how this interfaces are implemented.

Chapter 6 demonstrates the strengths of such a structured and integrated approach with a couple of cases in a real semiconductor fabrication environment.

Finally, Chapter 7 briefly summarizes this work with some conclusions and an outlook.