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Hydrogen bonding in β-Ga2O2 is investigated using hydrogen effusion measurements. The samples were grown by plasma-assisted pulsed laser deposition. With increasing deposition temperature, the total H concentration decreases from 8.1 × 1019 to 9.2 × 1018 cm−3. The dependence of the hydrogen chemical potential, μH, on the H concentration is derived from the effusion spectra and subsequently used to determine the H density-of-states distribution. β-Ga2O2 deposited at Tdep ≤ 723 K exhibits a needle-like peak in the H density-of-states distribution at ≈1.8 eV below the H transport states. With increasing Tdep, the H density-of-states changes and two broad peaks emerge that are located at ≈1.7 and 2.4 eV below the H transport states for Tdep ≥ 873 K. [ABSTRACT FROM AUTHOR]

The nature of hydrogen migration in β-Ga2O3 was investigated with respect to molecular or monatomic diffusion. For this purpose, β-Ga2O3 samples were grown by plasma-assisted pulsed laser deposition in which H and D were spatially separated. The samples were characterized using secondary-ion-mass spectrometry and hydrogen effusion measurements. The combination of these methods provides clear evidence for monatomic H and D diffusion in β-Ga2O3. [ABSTRACT FROM AUTHOR]

Raman backscattering measurements were performed on single crystal ZnO for different excitation wavelengths before and after ion implantation with hydrogen and nitrogen. In addition to the formation of H- and N-related defects due to implantation, anomalous Raman modes were observed. Recently, the anomalous Raman modes have been attributed to the disorder-induced activation of silent modes. However, we will show that part of the observed modes are due to the resonantly enhanced longitudinal optical phonons. [ABSTRACT FROM AUTHOR]

Hydrogen equilibration in polycrystalline silicon was investigated as a function of annealing time and temperature using electron spin resonance and hydrogen effusion measurements. During a vacuum anneal at least 1.5×1021 cm-3 H atoms are mobile in the lattice, however, only about 3.7×1018 cm-3 H atoms passivate Si dangling bonds. The results show that the annealing treatment can cause the vast majority of H atoms to accumulate in H stabilized platelets. Since defect passivation preferentially occurs at grain boundaries and platelet nucleation and growth are confined to the interior of single-crystal grains, H equilibration is governed by two spatially separated processes. Moreover, the data demonstrate that the hydrogen density-of-states distribution is dynamic and changes in response to experimental parameters. [ABSTRACT FROM AUTHOR]