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Si(111) wafers patterned with an array of vertical 100 µm-wide Al-doped (1 × 1019 cm−3) p-channels extending through the whole wafer were studied by X-ray Laue diffraction techniques. The X-ray techniques included projection topography, and measurement of rocking curves and cross sections in the vicinity of the 02\overline 2 reciprocal space node in the double- and triple-crystal geometry, respectively. The channels are uniform along the depth of the wafer, and their structural perfection is comparable to that of the silicon matrix between the channels. Simulation of the rocking curves was performed using the methods of the dynamical theory of X-ray diffraction. The rocking-curve calculations both taking into account and neglecting the effect of the instrumental function were carried out using the Takagi–Taupin equations. The calculated angular dependences of intensities of both diffracted and transmitted X-rays correspond well to the experimentally obtained rocking curves and demonstrate their high sensitivity to the structural distortions in the channel. An unambiguous reconstruction of strain and structural distortions in the Si(Al) channel using the Laue diffraction data requires further development of the theoretical model.

We present the results of optimization of the temperature gradient zone melting technique, also known as the thermomigration (ThM) technique, aimed on improvement of the quality of p-layers and formation of p-n junctions with sharper boundaries compared to those obtained by conventional thermal diffusion technique. In addition, ThM allows an expansion of the range of doping of silicon substrates with an acceptor impurity, usually limited by the solidus value. The ternary Al-Ga-Si and Al-Sn-Si melts were used as ligatures. The dependences of the migration rate of the liquid zones on temperature and composition for the Al-Ga and Al-Sn solvent metal are presented. The possibility of changing the acceptor concentration from 2·1019 cm−3 to 6·1019 cm−3 is shown. A threshold temperature of 1400 K was experimentally found for the ThM process with stable migration of triple liquid zones in a crystal. X-ray diffractional rocking curves and projection topography confirmed high structural quality of the Si(Al) p-layer with a thickness of 25 µm, obtained by ThM with stable moving liquid zones. The experimentally measured strain Δd/d=2.3×10−5 for the p-layer and the silicon substrate was used in the substitution model to estimate the Al concentration of 1×1019 cm−3. X-ray topographic images of the layers did not reveal both growth S-defects and misfit dislocations, confirming the high structural perfection of the layers and phase boundaries.

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