Development of a second-nearest-neighbor modified embedded atom method potential for silicon-phosphorus binary system

作者：Liu, Bin; Zhang, Hao; Tao, Junyong^*; Liu, Ziran; Chen, Xun; Zhang, Yun'an

来源：Computational Materials Science, 2016, 120: 1-12.

DOI：10.1016/j.commatsci.2016.04.002

• Second nearest-neighbor modified
• embedded atom method
• Genetic algorithm
• Silicon
• Phosphorus
• Mechanical properties

Phosphorus (P) is one of the most common impurities in silicon (Si). To investigate the effects of P on the mechanical properties of Si at nano or atomic scale, the second-nearest-neighbor Modified Embedded Atom Method model (2NN MEAM) potentials for pure P and Si-P binary system are developed using genetic algorithm (GA). The reference physical properties for the parameterization for pure P include cohesive energies, lattice constants, bulk moduli and first order pressure derivatives of experimentally-existing phases. The van der Waals interactions in P are not considered since it's beyond the description of MEAM and it's less important in covalently bonded Si-P compounds. For Si-P binary system, cohesive or formation energies, lattice constants and elastic constants of typical Si-P structures, properties of point defects and P-vacancy pairs are considered. The robustness of the newly developed potentials is examined by testing the thermal stability and transformation from non-equilibrium to ordered phase. The effects of P on the tensile behaviors of bulk Si are demonstrated. Results show that phosphorus lowers the fracture threshold and stiffness of bulk Si.

• 出版日期2016-7
• 单位中国人民解放军国防科学技术大学; 湖南师范大学