Papers by Keyword: Moore’s Law

Abstract: Elemental semiconductors play an important role in high-technology equipment used in industry and everyday life. The first transistors were made in the 1950ies of germanium. Later silicon took over because its electronic band-gap is larger. Nowadays, germanium is the base material mainly for γ-radiation detectors. Silicon is the most important semiconductor for the fabrication of solid-state electronic devices (memory chips, processors chips, ...) in computers, cellphones, smartphones. Silicon is also important for photovoltaic devices of energy production.Diffusion is a key process in the fabrication of semiconductor devices. This chapter deals with diffusion and point defects in silicon and germanium. It aims at making the reader familiar with the present understanding rather than painstakingly presenting all diffusion data available a good deal of which may be found in a data collection by Stolwijk and Bracht [1], in the author’s textbook [2], and in recent review papers by Bracht [3, 4]. We mainly review self-diffusion, diffusion of doping elements, oxygen diffusion, and diffusion modes of hybrid foreign elements in elemental semiconductors.Self-diffusion in elemental semiconductors is a very slow process compared to metals. One of the reasons is that the equilibrium concentrations of vacancies and self-interstitials are low. In contrast to metals, point defects in semiconductors exist in neutral and in charged states. The concentrations of charged point defects are therefore affected by doping [2 - 4].

Abstract: Microelectronics is a central area within information technology, which is still one of the most important global technologies. It will be shown that the development of integrated circuits is based on a long and fascinating history, which is unique in modern time. Yet, the fantastic growth in semiconductor electronics is due to a unique combination of basic conceptional advances, the perfection of new materials and the development of new device principles. A brief survey of the development of microelectronics is given by not only focusing on the history of microelectronics but also taking into account materials and market aspects. Since microelectronics is an extremely complex area, a few criteria and reference points for integrated circuits are given. Thereafter, some examples are presented indicating the rapidly changing state-of-the-art. It will be shown that the development of material science within the area of microelectronics is not always driven by scientific curiosity but often by arbitrary and not always obvious preferences. After a short discussion of the performance advantages and disadvantages of germanium, silicon and III-V compound semiconductors, the SiGe heterojunction bipolar transistor is taken as an example for demonstrating a few important differences in the performance of all-silicon devices with regard to silicon-based heterojunction devices in general. In conclusion, the impact of human enterprise and research policy on the development of microelectronics is briefly discussed.