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The investigation of the conditions for the generation of the misfit dislocations during the dopant impurities in silicon is of a grate interest for the defect control of the highly doped device structures [1 ,2J. Although the solid solubility of boron in silicon is lower than that of the phosphorus atoms, we expect that high densities of misfit dislocations to be induced in silicon even during the boron doping process (prediffusion step). We present in this paper our results concerning the control of the misfit dislocations after the boron diffusion in silicon at high concentrations (higher than the concentration of the intrinsic carriers n1, at the diffusion temperature). The defect control process consists in two main components: (i) the development of suitable criteria to evaluate the conditions for the generation of the misfit dislocations; (ii) the development of suitable techniques to reveal the region of the boron diffusion-induced misfit dislocations in the doped region. We evaluate the theoretical criteria for the generation of the misfit dislocations induced by the boron diffusion in silicon and we compared with the experimental results. We investigate by the bevel-angle selective chemical etching technique (BASCET) and by secondary ion mass spectroscopy (SIMS) the conditions for the generation of the misfit dislocations in the boron-doped silicon by predifflision at 1 100°C for 60mm. As we reported previously [3], the critical conditions for the generation of the misfit dislocation into the phosphorus highly-doped silicon layers can be explicitly given taking into account the behavior of the flat region of the phosphorus diffusion profile during the diffusion in silicon. In this paper we present an analytical model suitable to calculate the critical conditions for the generation of the misfit dislocation during the boron prediffusion in silicon is proposed. However, the substantial difference between the shape of the concentration profiles of boron with respect to that of phosphorus in silicon leads to corresponding differences in the way in which the problem of the misfit dislocation during the boron diffusion in silicon is approached. It is therefore necessary first of all to focus on the specific shape of the boron diffusion profile in silicon and the possibility of the evaluation of its properties.
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