Building the blue laser diode
The Blue Laser Diode: GaN Based Light Emitters and Lasers
Shuji Nakamura and Gerhard Fasol, Springer-Verlag, Berlin, Germany, 1997, 343 pages, $69.95
Because of the incredibly rapid development of gallium nitride (GaN), there has previously been no book available with more than a few paragraphs about this material. The Blue Laser Diode provides an extensive accumulation of data on the properties of GaN-based materials--crystal structure, transport, optical properties--in addition to a description of the metal-organic chemical-vapor-deposition (MOCVD) growth technique and device structures used by Shuji Nakamura to achieve record performance in various LEDs and lasers. The book chronicles Nakamura`s systematic development of MOCVD growth, p-type doping, and LED structures that led to the quantum-well laser.
In the preface, the authors claim the goals of their book are "to close the information ga¥. . . , to report the development of gallium nitride-based light emitters and lasers and their properties . . . , and to document an amazing success story of great historical importance." However, the book does not close the information ga¥between Nakamura and the rest of the world. There is minimal information about the two-flow MOCVD growth system and particularly what materials-characterization techniques and parameters of quality were used to improve growth or how critical the parameter space is for various growth parameters. The fact that it has taken very large research groups several years to approach Nakamura`s results suggests that in critical regions the growth parameter space approaches a delta function--thus requiring a long, arduous search. The detail of specific LED and laser-diode structures and their performance is more extensive; the book is not a "how to" manual.
The authors have a Web page (www.gifuro-technology.com/ bluelaserbook.html) that provides corrections, a useful feature. However, there are some irritating shortcomings, which will require a second edition. The book is largely an extension of Nakamura`s published papers over the past ten years, plus a review of progress and key contributions of others with an extensive list of 430 references. This is extremely useful because it is very authoritative, u¥to date, and all in one easily accessible place. However, several sections and tables served as introductory material in published papers and appear verbatim multiple times in the book, giving it a "glued together" feeling.
Overall, The Blue Laser Diode is a useful and interesting book and highly recommended to readers for both its technical content and a review of how this amazing revolution occurred. It is an essential starting point for any graduate student or researcher entering the field of wide-bandga¥semiconductors.
James S. Harris
JAMES S. HARRIS is James and Ellenor Chesebrough Professor of Electrical Engineering, Materials Science and Applied Physics, at Stanford University (Stanford, CA); e-mail: [email protected].