An approximate continuum theory for interaction between dislocation and inhomogeneity of any shape and properties J. Appl. Phys. 109, 113529 (2011) Direct comparison of boron, phosphorus, and aluminum gettering of iron in crystalline silicon J. Appl. Phys. 109, 073521 (2011) Impact of type of crystal defects in multicrystalline Si on electrical properties and interaction with impurities J. Appl. Phys. 109, 033504 (2011) Low-temperature acoustic properties of nanostructured zirconium obtained by intensive plastic deformation Low Temp.The isochronal and isothermal annealing characteristics of acceptor-doped GaAs:Be grown at low substrate temperatures (300 "C) by molecular-beam epitaxy (LTMBE) have been studied. The Be was introduced in a range of concentrations from lOi to 1019 cm -3. Electrical measurements of as-grown material up to the highest Be concentration of lOI cm -3 show that no free holes are contributed to the valence band even though Raman spectroscopy of the Be local vibrational mode indicates that the majority of the Be impurities occupy substitutional sites. It is proposed that Be acceptors are rendered inactive by the high concentration of Aso,-related native donor defects present in LTMBE material. The concentration of Aso,-related defects in the neutral charge state was estimated from infrared absorption measurements to be as high as 3 X 1019 cm -3. A distinct annealing stage at 5OO.Y!, similar to that found in irradiation-damaged and plastically deformed GaAs, marks a rapid decrease in the concentration of As o,-related defects. A second annealing stage near 800 "C corresponds to the activation of Be acceptors. The presence of gallium vacancies V,, was investigated by slow positron annihilation. Results indicate an excess concentration of Voa in LTMBE layers over bulk-grown crystals. Analysis of isothermal annealing kinetics for the removal of Aso=-related defects gives an activation energy of 1.7 kO.3 eV. The defect removal mechanism is modeled with VG,-assisted diffusion of AsGa to As precipitates.

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We report the results of deep level transient spectroscopy experiments with the second ionization level of the double donor defect (EL2) under uniaxial stress in p-type GaAs. We measure the shift in the hole emission rate as a function of stress applied in the [100] and [110] directions. By modeling the valence band with two independently displacing bands and appropriately derived effective masses, we determine the absolute hydrostatic pressure derivative of the defect to be 39±15 meV GPa−1. The shear contribution is negligible. These results are very different from those obtained for the first ionization level, which has a much higher absolute pressure derivative of 90 meV GPa−1.