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Elastic recoil detection analysis, using an incident beam of 200 MeV Au ions, has been used to measure indium nitride films grown by radio-frequency sputtering. It is shown that the films have nitrogen-rich stoichiometry. Nitrogen vacancies are therefore unlikely to be responsible for the commonly observed high background carrier concentration. Ultraviolet Raman and secondary ion mass spectroscopy measurements are used to probe the state of the excess nitrogen. The nitrogen on indium anti-site defect is implicated, though other possibilities for the site of the excess nitrogen, such as molecular nitrogen, or di-nitrogen interstitials cannot be excluded. It is further shown that a shift in the (0002) x-ray diffraction peak correlates with the excess nitrogen, but not with the oxygen observed in some samples. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The grain size for polycrystalline GaN, grown in low-temperature gallium-rich conditions, is shown to be correlated to the oxygen content of the films. Films with lower oxygen content were observed to have larger crystals with an increased tendency to a single-preferred crystal orientation. Elastic recoil detection analysis with heavy ions (i.e., 200 MeV [sup 197] Au ions) was used to determine the composition of the GaN films grown for the study, including the hydrogen, carbon, gallium, nitrogen, and oxygen content. Atomic force microscopy and x-ray diffraction were used to study the sample morphology. From these measurements, the available surface area of the films was found to be sufficient for a significant proportion of the oxygen present in the films to segregate at the grain boundaries. This interpretation is consistent with earlier theoretical studies of the formation and segregation of the V[sub Ga]-(O[sub N])[sub 3] defect complex at dislocation sites in gallium-rich GaN. For this work, however, the defect complex is believed to segregate at the grain boundary of the polycrystalline GaN. [ABSTRACT FROM AUTHOR]

Aluminum nitride insulating layers have been grown at room temperature with a film resistivity of 3.3 × 10[sup 16] Ω cm on mercury cadmium telluride substrates. Insulator breakdown fields of 640 MV/m were reached. Capacitance-voltage measurements with Al/AlN/Hg[sub 0.76]Cd[sub 0.24]Te metalinsulator-semiconductor devices demonstrate band bending at the semiconductor surface indicating that damage to the substrate was minimized during film growth. A fixed interface charge density (given here as total charge per unit area divided by the electron charge=Q[sub ss]/q) of +2 × 10[sup 11] cm[sup -]2 and slow interface state density of 4 × 10[sup 10] cm[sup -2] were measured. The procedures for achieving these high quality insulating layers are reported. Frequency dependent dielectric constant and dielectric loss tangent measurements, carried out at room temperature and 100 K, are also presented. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the room temperature optical absorption spectra of indium nitride films on the subband-gap energy range 40 meV to 20.0 eV. Schematic infrared absorption spectrum of indium nitride; Principal features of the infrared absorption measurements on sputtered indium nitride films; Analysis of optical excitation of the samples.

Describes the measurement of room-temperature band gap in indium nitride thin films prepared by reactive radio-frequency sputtering. Thickness range of the films; Contributory effects of the dependence of band gap on impurity concentration; Computational formulas for band gap measurement.

Presents electron mobilities in gallium nitride (GaN), indium nitride (InN) and aluminum nitride calculated over a range of temperatures, donor concentrations and compensation ratios using the variational principle (VP). Factors which the maximum mobilities of GaN and InN depend on; Fact that makes the calculation of the electron transport properties in the nitrides complicated; Difference between VP and a relaxation time approach to drift mobility.

Focuses on a study which examined the degree of applicability of the Mott variable range hopping model to electric transport processes in polypyrrole. Information on the potential applications of conducting polymers, such as polypyrrole; Example of possible structural features of polypyrrole; Range of the density of states of polypyrrole.

Presents a study which determine the insulator/semiconductor interface trap density by correlation deep level transient spectroscopy method. Analysis and derivation of the method; Results; Conclusion.

Proposes an approach that modeled the I-V characteristics of compositionally graded triangular heterostructure diodes by the use of a Wentzel-Kramer-Brillouin piecewise-approximation technique. Overview of graded barrier devices; Examination of diode characteristics; Calculation of the I-V characteristics of graded barrier structures.

Provides information on a study that investigated optical transitions in narrow, symmetric, triangular AlGaAs quantum well structures grown by molecular beam epitaxy. Description on graded quantum well models; Optical measurements; Conclusions.

Focuses on a study which analyzed the pressure dependence of the electrical conductivity of a range of polypyrrole samples doped at various levels in terms of variable-range hopping theory. Samples and model; Evidence for the presumption of invariance of wave-function inverse localization length; Definition of a single state-compressibility term.

Focuses on a study which evaluated optical transitions for the (001) AlGaAs/aluminum arsenide/gallium arsenide double-barrier superlattices for infrared photodetection. Calculation; Results and discussion; Conclusion.

Presents information on a study which investigated the photoluminescence excitation of gallium arsenide/gallium aluminum arsenide multiple-quantum-well structure. Influence of photon recycling on the optical-characteristics-photolumuniscense-excitation spectrum of the structure; Methodology of the study; Results and discussion.

Studies the dislocation scattering effects on electron mobility in indium compounds. Electric properties of indium compounds; Methodology of the study; Discussion on the results of the study.

Presents a study which observed electron mobility in InAs[sub1-x]Sb[subx]. Method of calculation; Information on the appropriate relaxation times for impurities, acoustic phonons, optical phonon and alloy scattering mechanisms; Details on the scattering mechanisms resuling from larger scale inhomogeneity.

Presents information on a study which calculated the electron mobility of indium arsenic--antimony by considering all the possible scattering mechanisms. Methodology of the study; Results and discussion; Conclusions.

Deals with a study which investigated the growth of thin films of carbon nitride on various substrates using low power radio frequency reactive sputtering of graphite in pure nitrogen plasma. Interest in carbon nitride thin films; Device in which carbon nitride is applicable; List of deposition techniques.

Presents a study which examined the conductivity of doped polypyrrole. Description of conductivity degradation in polypyrrole; Characteristics of the adsorption process; Effects of film thickness.

Discusses a study on film growth by method of laser-induced metalorganic chemical vapor deposition in aluminum nitride thin films. Methods for the growth of aluminum nitride thin films; Dielectric properties of the films; Measurement of relative permittivity and the loss tangent.

Presents a study which determined the alloy scattering potential for the ternary nitrides, Ga[sub1-x]Al[subx]N, N[sub1-x]Ga[subx]N, and In[sub1-x]Al[subx]N based on Phillips' electronegativity theory. Application of the growth of ternaries in quantum confinement and other heterostructures; Calculation of the alloy scattering potential; Overview of the alloy scattering potential for ternary alloys; Description of the electron drift mobilities.