Hydrogenation of diamond has been carried out using the electron-cyclotron-resonance microwave plasma chemical-vapor deposition apparatus. According to reflection high-energy and low-energy electron diffraction and X-ray photoelectron spectroscopy measurements, the natural- and synthetic-diamond surfaces maintained their crystallinity even after the hydrogenation. Seebeck effect measurement and the temperature dependence of the resistance revealed an appearance of deep acceptor levels in the hydrogenated diamond layer. The diffusion depth of the hydrogen by the plasma treatment (2 h, 830°C) was roughly estimated to be ∼0.6 µm from the drain current-voltage characteristics of a rudimentary MISFET using the hydrogenated diamond.

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This paper investigates the difference in crystal quality between strained-layer multiple quantum wells with compressive (+0.5%) and tensile strains (-0.5 %). For the compressive strain, the photoluminescence intensity decreased and the length of fringe bending increased from 250 Å to 500 Å when the number of periods increased from 5 to 15. The amount of fringe bending increased when the InP thickness decreased, especially when the strain was compressive. We also investigated the relaxation process in an InGaAs layer as a function of the layer thickness (from 25 nm to 2 µ m). For a compressive strain (+1.1%), misfit dislocations were observed near the interface between InGaAs and InP substrate. On the other hand, for a tensile strain (-1.1 %), we observed cracks instead of misfit dislocations. Moreover, the cracks were considered to increase the X-ray full width at half maximum of both the InGaAs lattice-mismatched layer and the InP substrate.