The growth of extrinsic stacking faults associated with SiP platelets induced by phosphorus predeposition in thin silicon foils has been followed by transmission electron microscopy. The role of the precipitates and of the phosphorus diffusion on the climb of the Frank partials is discussed. Unfaulting reactions, observed to annihilate isolated extrinsic Frank loops, are assumed to take place also in the case of the stacking faults associated with precipitates, resulting in the generation of 60° perfect dislocations, which have been revealed by x-ray topography. Different climb rates for the 60° dislocations have been observed after predeposition experiments performed by varying the oxidation and the phosphorus-doping kinetics; the relationship between these two parameters and the vapor partial pressures of the gas flowing in the furnace has been obtained as a result of careful experimental work. From the results of all our experiments, it has been deduced that the ingoing phosphorus, rather than the associated oxidation, is the main factor responsible for the climb of both partial and unit dislocations. The growth of these defects is attributed to the interstitial supersaturation produced at the interface Si-SiO2 by the phosphorus atoms entering the silicon lattice.

The advantages in the use of high‐voltage electron microscopy in the observation of reverse‐biased p–n junctions are considered. Some theoretical results concerning the influence on the Fresnel image of the electric field inside the junction and of the external leakage field are presented for different values of the accelerating voltage. Preliminary experimental results obtained with a Hitachi microscope at the operating voltages ranging between 400 and 1000 kV are shown and compared with theoretical predictions. They indicate that the high voltage electron microscope may be a useful tool in investigating the internal electric field associated to the depletion layer of reverse‐biased p–n junctions. The working conditions are reported and discussed.

A method to reduce the mutual coupling in wide-band multilayer patch array operating in C band is presented. The proposed device use conveniently sized meander line parasites printed on the same substrate of the upper patch. Measurements on a 2 × 2 prototype shows a measured bandwidth of about 19.6% centred at 5.1 GHz, therefore adequate to cover the whole WLAN frequency range. The meander lines allow to reduce the patch mutual coupling by about 2.4 dB.

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Ion-implanted Si wafers were irradiated in air with a Q-switched ruby laser and then isochronally annealed between 450 and 850 degrees C. Within the depth corresponding to the melted thickness, a considerable amount of alpha-quartz was detected in the 700-800 degrees C range. Copper precipitation was observed associated with alpha-quartz formation. The role of a dissolved oxygen supersaturation, which seems to be generated by laser irradiation of air-exposed samples, is discussed briefly in the light of the use of laser annealing techniques for electronic device fabrication.