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In an effort to combine group III-V semiconductors with carbon nanotubes, a simple solution-based technique for gallium functionalization of nitrogen-doped multi-wall carbon nanotubes has been developed. With an aqueous solution of a gallium salt (GaI(3)), it was possible to form covalent bonds between the Ga(3+) ion and the nitrogen atoms of the doped carbon nanotubes to form a gallium nitride...

We present a simple analytic scheme for calculating the binding energy of excitons in semiconductors that takes full account of the existing anisotropy in the effective mass, as a complement to the qualitative treatment in most textbooks. Results obtained for excitons in gallium nitride form the basis for a discussion of the accuracy of this approach. Zusammenfassung. Wir präsentieren ein einfa...

We review the surface stability and growth kinetics of III-V and III-nitride semiconductors. The theoretical approach used in these studies is based on ab initio calculations and includes gas-phase free energy. With this method, we can investigate the influence of growth conditions, such as partial pressure and temperature, on the surface stability and growth kinetics. First, we examine the fea...

The structure of boron nitride nanotubes is investigated using a generalized tight-binding molecular dynamics method. It is shown that dynamic relaxation results in a wave-like or ‘rippled’ surface in which the B atoms rotate inward and the N atoms move outward, reminiscent of the surface relaxation of the III–V semiconductors. More importantly, the three different morphologies of the tube clos...

Although the demand for high-speed telecommunications has increased in recent years, the performance of transistors fabricated with traditional semiconductors such as silicon, gallium arsenide, and gallium nitride have reached their physical performance limits. Therefore, new materials with high carrier velocities should be sought for the fabrication of next-generation, ultra-high-speed transis...

Ever since Gallium Nitride based high electron mobility transistor (HEMT) operation was demonstrated (Khan, 1993), there is a tremendous interest in the design and growth of GaN based transistors for high power device applications. The nitride semiconductors have wide application in the fields of high electron mobility transistors (HEMTs), light emitting diodes, and various high power electroni...

The early stages of thin film growth from the rf glow discharge of silane-based gas mixtures have been systematically studied by structural characterizations of the silicon based multilayers. The x-ray diffraction, its rocking curve and x-ray interference of hydrogenated amorphous silicon(a-Si:H, 10 % 200 A thick)/stoichiometric silicon nitride (a-SigNq:H, 25 % 250 A) multiple layers have been ...