This is a well-organized, concise introduction to the field of compound semiconductors and their applications in optoelectronic and electronic devices. The fundamental science and technology necessary to understand research in this field is covered in easy-to-read text: short paragraphs, bullet lists of key points, copious figures, and short chapters (typically less than 20 pages). There is a logical flow from basic properties through process technologies to device applications. The emphasis is on III–V compound semiconductors, particularly gallium arsenide, indium phosphide, and gallium nitride, with the occasional comparison to silicon. Aside from the coverage on gallium nitride, many of the characterization techniques and materials processing methods have been well established and written about for close to 40 years; more than 75% of the references are from before 2000. Still, Scholz’s presentation is fresh with its inclusion of quantum effects, low dimensional systems, and group III nitrides and their distinctive properties.
The book is roughly divided into four sections.The first four chapters cover the basic properties of compound semiconductors and their synthesis. The defining general properties of semiconductors such as crystal lattices, energy bandgaps, and charge-carrier statistics are covered in chapter 1. The distinguishing properties of compound semiconductors, their direct bandgaps, the ability to control the bandgap by forming alloys such as AlxGa1–xAs, and energy bandgap discontinuities realized with heterojunctions, are described in chapter 2. Methods of growing bulk single crystals from melts (the Czochralski method) and solutions (the Bridgman method) are detailed in chapter 3. Chapter 4 describes the main epitaxial growth methods, including liquid-phase epitaxy, metal–organic vapor-phase epitaxy, and molecular beam epitaxy.
The second section, chapters 5–7, is an overview of characterization methods. How the electrical properties of charge mobility and carrier concentrations are measured by the Hall effect and CV methods is the subject of chapter 5. Optical characterization by photoluminescence and absorption, and structural characterization by x-ray diffraction of the properties are recounted in chapters 6 and 7.
The third section describes some of the distinguishing characteristics important to compound semiconductors. Chapter 8 chronicles the property changes introduced by quantum wells and their applications. The importance of strain as a design parameter for changing the band structure and its influence on the critical thickness are covered next in chapter 9. Chapter 10 describes the methods of synthesizing quantum wells, wires, and dots. Group III nitrides are distinctive enough to have their own chapter; the challenges of doping, forming ternary alloys in the nitride system, and the implications of polarization and piezoelectricity are described in chapter 11.
The final section, chapters 12 and 13, is on devices at which compound semiconductors excel due to their direct bandgaps and high carrier mobilities. These include optoelectronic devices, such as light-emitting diodes, laser diodes, and solar cells, and electronic devices, especially field-effect transistors and heterobipolar transistors.
This could be used as a textbook, as questions are included at the end of each chapter. There are a few questions that require quantitative numerical solutions, but the vast majority are more qualitative, requiring only descriptive answers.
This book presents a good overview of compound semiconductors, their properties, synthesis, characterization, and device applications. It is appropriate for upper-level undergraduates or graduate students.
Reviewer: J.H. Edgar, Department of Chemical Engineering, Kansas State University, USA.
