The paper combines two theoretical approaches – the method of grazing dynamical diffraction (which allows performing the nondestructive structural diagnostics of defects in the near‐surface layers) with efficient numerical simulation method (which enables computation of electron structure in realistically large systems with millions of atoms) – for studying electronic properties in uniaxially strained graphene layers with point defects: impurity atoms. Electron density of states (DOS) is proved sensitive to the direction of uniaxial tensile deformation and configuration of defects. If defects are distributed orderly, the band gap value (estimated from the DOS curves) varies nonmonotonically versus the stretching deformation along zigzag‐edge direction. In this case, the minimal tensile strain required for the band gap opening is found to be smaller than that for defect‐free graphene, and the maximum band gap value is close to that predicted for failure limit of the defect‐free graphene. The obtained results play a significant part for band gap engineering in graphene: via spatial configuring of defects and external tensile stresses.

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Radio-frequency (RF) hydrogen plasma treatment, thermal annealing in a furnace, and rapid thermal annealing of high-dose P+ ion implanted p-type Ge layers have been studied by Raman scattering spectroscopy, atomic force microscopy, secondary ion mass spectrometry, electrochemical capacitance-voltage profiling, four-point probes method, and x-ray reflectometry. It was shown that low-temperature RF plasma treatment at temperature about 200 degrees C resulted in full recrystallization of amorphous Ge layer implanted by P+ ions and activation of implanted impurity up to 6.5 x 10(19) cm(-3) with a maximum concentration at the depth of about 20 nm. Rapid thermal annealing (15 s) and thermal annealing (10 min) in nitrogen ambient required considerably higher temperatures for the recrystallization and activation processes that resulted in diffusion of implanted impurity inside the Ge bulk. It was demonstrated that RF plasma treatment from the samples with front (implanted) side resulted in considerable stronger effects of recrystallization and activation as compared with the same treatment from the back (unimplanted) side. The experiment shows that nonthermal processes play an important role in enhanced recrystallization and dopant activation during the RF plasma treatment. Mechanisms of enhanced modification of the subsurface implanted Ge layer under plasma treatment are analyzed. (C) 2017 American Vacuum Society

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