Gallium nitride semiconductor

Pankove J I and Moustaka T D 1997 Gallium Nitride (Semiconductors and Semimetals 50) (Boston Academic)... 

Bulk elastic modulus, of binary compound semiconductors, 22 145, 146-147t Bulk enzymes, from genetically engineered microbes, 22 480 Bulk erosion, 9 78 Bulk fluid velocity method, 16 688 Bulk gallium nitride, supercritical ammonia solution growth of, 14 96-97 Bulk gases... 

Blue lasers allow higher resolution, and hence higher density of optical storage of information, on devices such as DVDs than the infrared GaAs lasers allow. The earliest blue lasers were based on ZnSe but their lifetime proved too short for commercial applications. Lasers based on gallium nitride (GaN), first demonstrated in 1995, have proved to have greater lifetimes. In these lasers, the photons are produced not in a bulk semiconductor but in quantum wells. 

From an optical viewpoint, on the other hand, the difference between semiconductors and insulators lies in the value of Eg. The admitted boundary is usually set at 3 eV (see Appendix A for the energy units) and materials with Eg below this value are categorized as semiconductors, but crystals considered as semiconductors like the wurtzite forms of silicon carbide and gallium nitride have band gaps larger than 3 eV, and this value is somewhat arbitrary. The translation into the electrical resistivity domain depends on the value of Eg, and also on the effective mass of the electrons and holes, and on their mobilities. The solution is not unique moreover, the boundary is not clearly defined. Semi-insulating silicon carbide 4H polytype samples with reported room temperature resistivities of the order of 1010flcm could constitute the... 

Silicon carbide. 2. Gallium nitride. 3. Semiconductors. I. Wood, Colin E.C. II. Title. 

The very high thermal conductivity and close lattice match to gallium nitride (GaN), another wide band gap semiconductor, has recently... 

In materials science we often divide materials into distinct classes. The primary classes of solid materials are ceramics, metals, and polymers. This classification is based on the types of atoms involved and the bonding between them. The other widely recognized classes are semiconductors and composites. Composites are combinations of more than one material and often involve ceramics, such as fiberglass. Semiconductors are materials with electrical conductivities that are very sensitive to minute amounts of impurities. As we will see later, most materials that are semiconductors are actually ceramics, for example, gallium nitride, the blue-green laser diode material. 

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