We have produced epitaxial Si1−x−yGexCy/Si heterostructures by rapid thermal chemical vapor deposition using methylsilane SiCH6). These layers were grown in the SiH4/GeH4/SiCH6/H2 system between 550 and 600 °C at 1.5 Torr. Suitable process conditions were found that allow very efficient substitutional carbon incorporation. No carbon cross contamination was observed. Crystal quality, chemical composition, and lattice strain were deduced from Nomarski microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, secondary ion mass spectrometry, and x-ray diffraction. Defect-free alloy layers with compositions of up to 20 at.% Ge and 2.2 at. % C were produced. The lattice parameter was tailored so that the strain in these layers gradually moved from compressive to tensile. A tensile strain of up to 0.35% was achieved.

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To investigate the effect of an adjacent hole on the blast-induced stress concentration in rock blasting, a rock blasting model with an adjacent hole is explored through theoretical analysis and numerical simulation. The commercial software LS-DYNA is utilized to simulate adjacent hole effect in rock blasting, in which the Johnson–Holmquist concrete material model is used to simulate rock and the high-explosive-burn-explosive and the equation of state of JWL are used to simulate explosive. Influences of the key parameters of adjacent hole effect in rock blasting, pitch of holes, adjacent hole diameter, and uncoupled medium in a blasting hole are extensively explored. According to the simulation results, when the explosion stress wave spreads to the adjacent hole wall, the tangential stress on the adjacent hole wall induced by the explosion stress wave is always greater than the radial stress. Adjacent hole diameter has a major effect on stress concentration, but with the adjacent hole diameter increasing, the stress concentration phenomenon weakens and the free surface effect of the adjacent hole plays a more important role.

All deposits were prepared using an automated LCVD system, which has previously been described in detail. 17,18 Briefly, a 519 J ournal

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