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The interfacial characteristics of GaInP GaAs heterostructures reveals that a photoluminescence (PL) peak having an energy of 1.425 electron volts is found in samples with GaInP-to-GaAs interfaces. The interfacial characteristics are determined by performing PL measurements. The PL peak is caused by the excitonic recombination in the heterostructures.

We report on the technology and the electrical properties of two different contact systems on n-GaAs nanowires. Annealed Ge/Ni/Ge/Au and Pd/Ge/Au multilayer metallization were investigated. Rapid thermal annealing at temperatures common for identical contact systems on n-GaAs layers is found to be crucial due to an enhanced out-diffusion of the Ga component into the Au contact layer. The maximum annealing temperatures ensuring intact nanowires are 320 °C for Ge/Ni/Ge/Au and 280 °C for Pd/Ge/Au. The fabricated Pd/Ge/Au contacts reveal a specific contacts resistance of 2.77 × 10-7 Ωcm2, which is about one order of magnitude lower compared to the values of Ge/Ni/Ge/Au and also lower than Pd/Ge/Au contacts on bulk material (1.2 × 10-6 Ωcm2). [ABSTRACT FROM AUTHOR]

InGaAs nanowhiskers were grown by metal-organic vapor-phase epitaxy on (111)B GaAs substrates using the vapor-liquid-solid growth mode. The diameter of nanowhiskers was defined by monodisperse gold nanoparticles deposited on the GaAs substrate from the liquid phase. By adjusting the triethylgallium to trimethylindium flow ratio, InxGa1-xAs whiskers with various compositions were realized. The composition characterization of the grown whiskers was done by high-resolution x-ray diffractometry. A detailed analysis of measured spectra allowed resolving the presence of an InGaAs three-dimensional layer between whiskers. High-resolution transmission electron microscopy investigation revealed the lattice constant of the grown whisker structures, which agrees with the whisker composition defined by x-ray diffractometry. Finally, low-temperature photoluminescence measurements of the realized InGaAs whiskers were carried out. [ABSTRACT FROM AUTHOR]

We systematically investigated the DC-characteristics of Si/SiGe interband tunneling diodes as a function of layer structure and device geometry. The Si spacer thicknesses Xp and XN between the intrinsic SiGe layer and the p- and n-δ-doped layers were varied. We obtained a peak current density of 16 kA/cm² and a peak-to-valley current ratio of 2.7 (with a device area of 45 μm²) for a structure with Xp= 0 nm and XN= 1 nm. A good homogeneity of all measured diode parameters was achieved over the wafer area. [ABSTRACT FROM AUTHOR]

Both the self- and non-self-aligned graded-base InP/InGaAs/InP double heterostructure bipolar transistors (DHBTs) were passivated by room-temperature deposited SiNx. Current gains were found to increase significantly after SiNx passivation. The passivation resulted in an increase in the leakage current of base-collector junction. The larger leakage current in the non-self-aligned DHBT made the sudden increase of the collector current in the common-emitter I–V curve occur at smaller collector-emitter bias than that in the self-aligned DHBT, which has smaller leakage current. Further increase in the current gain was found after the DHBTs were exposed to air for 200 days. The leakage current in the base-collector diode was reduced. The sudden increase of the collector current in the non-self-aligned DHBT in the common-emitter I–V characteristics was also suppressed. Investigation of reverse Gummel plots showed that the surface recombination in the base-collector diode was suppressed by the passivation. The leakage current in the base-collector diode was attributed to the increase of the generation rate. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Focuses on a study which presented a photoluminescence (PL) analysis of gallium indium phosphide/gallium arsenide single-quantum well structures grown by metal-organic vapor-phase epitaxy. Description of the sample and procedure; Estimation of the growth temperature dependent conduction and valence band discontinuity of the heterojunction; Results of x-ray diffraction measurements and simulations.

Studies the use of high resolution x-ray diffraction thin indium arsenide and gallium arsenide layers grown on InP substrates by low-pressure metalorganic vapor-phase epitaxy. Growth parameter and structural parameter of the investigated samples; Superlattice periods determined from the observed satellites separations; Enlargement of an experimental rocking curve of sample IX in the vicinity of the zeroth-order peak.

The surface recombination at extrinsic base region in graded-base InGaAs-InP heterostructure bipolar transistors (HBTs) is studied. The combination of the surface recombination mechanisms results in the bias-dependent ideality factor in the nonself-aligned HBT.