[SY-C6] Symposium C-6

[SY-C6] Investigation of the energy pathway for generation of dislocations in silicon at Σ3 grain boundaries with the kinetic Activation-Relaxation Technique

^○Simen Nut Hansen Eliassen¹, Normand Mousseau³, Mickaël Trochet³, Yanjun Li¹, Jesper Friis², Inga Gudem Ringdalen² (1.Dept. of Materials Science and Engineering, Norwegian Univ. of Science and Technology, Norway, 2.SINTEF Materials and Chemistry, Norway, 3.Dept. of Physics, Univ. de Montréal, Canada)

Multicrystalline silicon (mc-Si) is widely used for solar cell applications due to the low production costs and high efficiency. However, the crystallization processes of mc-Si induces different kinds of defects in the structure which reduces the overall conversion efficiency. Regions containing a high density of defects such as dislocations are especially detrimental. The origin of dislocations is an ongoing debate. Previous studies indicates that generation of dislocations in mc-Si can occur at Σ3 grain boundaries; however, a detailed atomistic description of the mechanisms governing the generation of dislocations is lacking. To cast light on the mechanisms behind generation of dislocations, we have deployed the kinetic Activation-Relaxation Technique (k-ART), an off-lattice Kinetic Monte Carlo code with an on-the fly cataloging of events. K-ART allows us to construct an extensive description of the energy landscape around defects and obtain the energy barriers of diffusion pathways. Furthermore, this is achievable at a time scale and in a temperature regime relevant to experimental observations. In this work, we have constructed a model structure containing an asymmetric and a symmetric Σ3 grain boundary which are joined together to form a kink. We present here an energy pathway for generation of dislocations from the kink with the associated energy barriers, and how the energy barriers is affected when the system is subjected to a shear force.