Point defects generated during motion of dislocations in silicon have been investigated using their reaction with gold atoms during gold in‐diffusion. Deep Level Transient Spectroscopy (DLTS) measurements in n‐ and p‐type samples have revealed that in regions with dislocation densities of 104–106 cm−2, the concentration of gold atoms is by 1.5–2 orders of magnitude higher than in the dislocation‐free regions of the same samples. The increase in the gold atom concentration in the regions containing dislocations is explained by the presence of some vacancy complexes generated by dislocations moving in their slip planes. Just after dislocation motion, most of these complexes are not detectable by DLTS. They become observable in DLTS due to their reaction with gold atoms.

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We show experimentally that dislocations in Si crystals can generate some unknown vacancy complexes Vxtrailin their slip planes during their motion at 600°C. Most of these “dislocation trail defects” are not electrically active but can be detected by their reaction with gold atoms during in-diffusion experiments. It was also shown that contrary to gold, the Vxtrail-complexes do not react with interstitial Ni atoms. It means that the binding energy Ebindof Vxtrailcomplexes is quite high (Ebind>2.5eV), higher than the binding energy of vacancy complexes generated during FZ-Si crystal growth. It was also shown that Ni in-diffusion results in a strong increase of electron-hole recombination at dislocations and in a strong increase of dislocation-related DLTS C-line.

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We investigated the development of dislocation-related DLTS spectra in n-CZ-Si crystals with small (about 7.104 cm-2) number of long individual dislocations depending on the distance L that dislocations traveled during deformation at 600oC and on the velocity of dislocations. We found that a typical dislocation-related DLTS signal appeared only when dislocations traveled a significant distance that is more than 150-200μm, and it depended strongly on dislocation velocity. The results were interpreted on the assumption that the DLTS signal corresponds to some core defects and atomic impurities accumulated on the dislocations during their slow motion. At high concentration of deep level defects on dislocations a strange “negative DLTS” signal was observed. This can be explained by electron tunneling between deep defects along dislocations.

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Our progress in further development of “Induction Melting in Cold Crucible” (IMCC) method for continuous growth of mc‐Si for PV applications is reported and characteristics of material production by this method are presented. The productivity of our IMCC equipment is more than three times higher than the productivity of standard equipment for Directional Solidification (DS) in quartz crucible, the process is continuous and eliminates the need to consume expensive quartz crucibles. The properties of IMCC mc‐Si were investigated by Light Beam Induced Current (LBIC), Time of Flight Second Ion Mass Spectroscopy (TOF‐SIMS) measurements etc. The results obtained are compared with the properties of standard MC‐Si produced by DS in quartz crucibles. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)