Landolt-Börnstein / New Series

Transcription

1 Landolt-Börnstein / New Series

2 Landolt-Börnstein Numerical Data and Functional Relationships in Science and Technology New Series Editor in Chief: W. Martienssen Units and Fundamental Constants in Physics and Chemistry Elementary Particles, Nuclei and Atoms (Group I) (Formerly: Nuclear and Particle Physics) Molecules and Radicals (Group II) (Formerly: Atomic and Molecular Physics) Condensed Matter (Group III) (Formerly: Solid State Physics) Physical Chemistry (Group IV) (Formerly: Macroscopic Properties of Matter) Geophysics (Group V) Astronomy and Astrophysics (Group VI) Biophysics (Group VII) Advanced Materials and Technologies (Group VIII) Some of the group names have been changed to provide a better description of their contents.

3 Landolt-Börnstein Numerical Data and Functional Relationships in Science and Technology New Series / Editor in Chief: W. Martienssen Group III: Condensed Matter Volume 34 Semiconductor Quantum Structures Subvolume C Optical Properties Part 3 E. Kasper, N. Koshida, T.P. Pearsall, Y. Shiraki, G. Theodorou, N. Usami Edited by E. Kasper and C. Klingshirn

4 Online Version: ISSN (Condensed matter) ISBN Springer Berlin Heidelberg New York Print Version: ISSN (Condensed matter) ISBN Springer Berlin Heidelberg New York Library of Congress Cataloging in Publication Data Zahlenwerte und Funktionen aus Naturwissenschaften und Technik, Neue Serie Editor in Chief: W. Martienssen Vol. III/34C3: Editors: E. Kasper, C. Klingshirn At head of title: Landolt-Börnstein. Added t.p.: Numerical data and functional relationships in science and technology. Tables chiefly in English. Intended to supersede the Physikalisch-chemische Tabellen by H. Landolt and R. Börnstein of which the 6th ed. began publication in 1950 under title: Zahlenwerte und Funktionen aus Physik, Chemie, Astronomie, Geophysik und Technik. Vols. published after v. 1 of group I have imprint: Berlin, New York, Springer-Verlag Includes bibliographies. 1. Physics--Tables. 2. Chemistry--Tables. 3. Engineering--Tables. I. Börnstein, R. (Richard), II. Landolt, H. (Hans), III. Physikalisch-chemische Tabellen. IV. Title: Numerical data and functional relationships in science and technology. QC ' This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in other ways, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer- Verlag. Violations are liable for prosecution act under German Copyright Law. Springer is a part of Springer Science+Business Media springeronline.com Springer-Verlag Berlin Heidelberg 2007 Printed in Germany The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product Liability: The data and other information in this handbook have been carefully extracted and evaluated by experts from the original literature. Furthermore, they have been checked for correctness by authors and the editorial staff before printing. Nevertheless, the publisher can give no guarantee for the correctness of the data and information provided. In any individual case of application, the respective user must check the correctness by consulting other relevant sources of information. Cover layout: Erich Kirchner, Heidelberg Typesetting: Author and Redaktion Landolt-Börnstein, Darmstadt Printing and binding: AZ Druck, Kempten SPIN: (Online) (Print) 63/ Printed on acid-free paper

5 Editors E. Kasper Universität Stuttgart Institut für Halbleitertechnik Stutttgart, Germany C. Klingshirn Universität Karlsruhe (TH) Institut für Angewandte Physik Karlsruhe, Germany Authors E. Kasper Universität Stuttgart Institut für Halbleitertechnik Stutttgart, Germany N. Koshida Tokio University of A&T Faculty of Electrical and Electronics Engineering Koganei, Tokyo , Japan T.P. Pearsall 18, Rue des Petits Champs Paris, France Y. Shiraki Musashi Institute of Technology Tokyo , Japan G. Theodorou Aristotle University Department of Physics Solid State Physics Section Thessalonoki, Greece N. Usami Tohoku University Institute for Materials Research Sendai , Japan Editorial office Gagernstraße 8, Darmstadt, Germany fax: +49 (6151) Internet

6 Preface The first two subvolumes III/34Cl and C2 on the Optical Properties of Semiconductor Quantum Structures have been well received by the scientific community. They concentrated on theoretical concepts (chapter 1), experimental methods (chapter 2), III-V semiconductors (chapter 4), I-VII semiconductors (chapter 6), and IV-VI semiconductors (chapter 7) in subvolume Cl. The II-VII materials (chapter 5) have been treated in subvolume C2. The present subvolume III/34C3 finishes the review on optical properties, by adding the chapter 3 on group IV materials. There are exhaustive data on bulk materials including optical properties, starting from diamond C and going over SiC, Si, Ge, to the semimetal grey Sn, and including their alloys see e.g. Landolt-Börnstein, New Series, Group III, Vol. 41Al 1 and 2, and A2 1 and 2. Silicon is the backbone of the worldwide semiconductor industry. It is an indirect gap material, which seriously hampers its use in light emitting or even laser diodes. There are some ideas to overcome this problem by forming group IV quantum structures like Si/Ge superlattices or nanocrystals. This hope triggers to a large extend the applied aspects of the research on the optical properties of group IV quantum structures. Though there are also relevant publications on the optical properties of group IV quantum structures involving C or Sn, the by far largest part of work in this field is devoted to the system Si/Ge. Therefore we concentrate here on this system. The outline of this subvolume follows essentially the concept of the two preceding ones Cl and C2, but with some differences in the details. The first section 3.1 brings again some basic properties like the energy gaps or the effective masses and proceeds then with in-depth information on the growth processes and the influence of the lattice misfit on the growth techniques. It is not possible in the Si/Ge system to circumvent this problem as it is in the ternary or quaternary systems like AlGaAs, InGaAsP or ZnMgSSe, where the values of band gap and lattice constant can be chosen within some limits independently. For this reason we bring in section 3.2 an overview of the influence of strain on the band structures of Si and Ge and on the relative band line up between the two materials, going in this field even more into depth in some of the following sections. After these two introductory sections we start, similar as in the other subvolumes, in section 3.3 with single, coupled, and multiple quantum wells. Section 3.4 is then devoted to the optical properties of superlattices. Section 3.5 combines the data on quantum wires and on a special group of quantum dots, namely those prepared by lithography of quantum wells, of selforganized quantum dots or islands occurring in a similar way as in various III-V and II-VI systems such as InAs/GaAs or CdSe/ZnSe. Furthermore nanoclusters of e.g. Si in SiO 2 are considered here. Nanoislands or localization sites occurring usually in quantum wells due to thickness and/or composition fluctuations and with lateral dimension which hardly result in quantization effects are only marginally treated in section 3.5. A separate section 3.6 is devoted to porous or nanocrystalline Si. The observation of visible luminescence from porous Si or Ge triggered a lot of research, caused again by the hope to obtain materials based on these group IV semiconductors which allow the fabrication of efficient light emitting devices. During the years of investigation it became obvious that not all light emission in these etched structures is due to Si

7 nanocrystals, but that there may be also contributions from siloxanes and similar Si x O y H z compounds formed during the etching process. Since the latter lead beyond the scope of this compilation, section 3.6 is devoted to results where the important role of Si nanocrystals is rather well established. As in the two preceding subvolumes it is not the aim to cite and comment all work published so far on optical properties of group IV quantum structures but to explain and to highlight prominent examples. Some of the topics which are extensively studied in quantum structures of direct gap semiconductors such as four wave mixing, lasing processes etc. are of minor importance for the group IV semiconductors. Therefore the detailed structuring of this subvolume deviates in parts from the one of the chapters on e.g. direct gap III-V, II-VI or I-VII quantum structures. Acknowledgements The editors thank all co-authors of this subvolume for the committed and careful preparation of their manuscripts and the fruitful and stimulating cooperation during this book project. Thanks are due to Prof. Dr. W. Martienssen, the editor in chief of Landolt-Börnstein, for his steady and demanding interest in the progress of this work, and last but not least to Drs. R. Poerschke, W. Polzin and S. Scherer from Springer for their patient, competent and extremely helpful support during the production on this book. Stuttgart and Karlsruhe, January 2007 The Editors

8 Table of contents Semiconductor Quantum Structures Subvolume C3: Optical Properties (Part 3) (edited by E. KASPER and C. KLINGSHIRN) 3 Group IV semiconductors Basic properties, growth and preparation methods of group IV heterostructures (by E. KASPER) Epitaxial growth processes Lattice mismatch and its implication on critical thickness and interface structure Virtual substrates and strain relaxation References for Influence of strain on bandstructure (by E. KASPER) Hydrostatic strain Uniaxial strain Band alignment of strained SiGe Average valence band energy E 0 v,av Compressive strain Tensile strain References for Single and coupled quantum wells: SiGe (by N. USAMI and Y. SHIRAKI) Introduction Photoluminescence from SiGe/Si quantum wells: Spectral features Excitation power dependence of photoluminescence Temperature dependence of photoluminescence Quantum confinement effect Effect of post-growth annealing Effect of electric field Effect of external stress Fermi-edge singularity Time-resolved photoluminescence Growth mode transition Type-II strained Si quantum well Coupled quantum wells Electroluminescence Interband absorption Intraband absorption Second-harmonic generation Phonon modes Cyclotron resonance References for

9 Table of Contents ix 3.4 Optical properties of Si/Ge superlattices (by G. THEODOROU and E. KASPER) Introduction The empirical tight-binding model Uniaxial strain along the [001] direction Uniaxial strain along the [111] direction Optical properties Si/Ge SLs grown along the [001] direction Electronic properties Optical properties Interface intermixing Si/Ge SLs grown along the [111] direction Raman spectroscopy Zone-folded acoustic phonons Confined optical modes and interface modes Photoluminescence (PL) Effect of hydrostatic pressure on the PL Electroluminescence (EL) Photoconductivity (PC) and optical Junction Space Charge Techniques (JSCT) Wannier-Stark localization Spectroscopic ellipsometry Piezoreflectance and electroreflectance Second-harmonic generation Quantum dot superlattices (QDSL) Conclusions References for Si, Ge, and SiGe quantum wires and quantum dots (by T.P. PEARSALL) Introduction Silicon and germanium quantum-wire quantum-dot structures Synthesis of quantum wires and quantum dots Self-organized epitaxy of quantum dots Lithographic definition of quantum structures Synthesis of free-standing Si quantum dots Photoluminescence properties of Si nanoclusters Si quantum dots formed by controlled segregation of excess Si in SiO Si quantum dots formed by the controlled segregation of excess Si in SiN x Applications of SiGe quantum-dot structures SiGe quantum-dot photodetectors Si quantum-dot light-emitting diodes Er-doped Si-SiO 2 nanocluster optical amplification Si quantum-dot memories Conclusions References for Luminescence and related properties of nanocrystalline porous silicon (by N. KOSHIDA) Introduction An overview of nanostructured silicon Fabrication technology Nanocrystalline porous silicon Dry-processed silicon nanocrystallites

10 x Table of Contents Nanocrystalline porous silicon Properties as a confined system Photoluminescence Electroluminescent devices Related functions Carrier charging effects Ballistic transport and emission Thermally induced acoustic emission Toward monolithic functional integration Conclusions References for