Effects of B and P Doping on Electronic Structure and Lithium Diffusion Properties of Si(100) Surface

Surface and lithium diffusion properties of Si(100) doped with B and P are studied using first-principles plane wave pseudopotential method. The calculated results show that B-doping has a greater effect on Si(100)-7 than P-doping. For 0.5 mol% P-doping, the population difference between Si5P bonds and Si5Si3 bonds is 0.02. For 0.5 mol% B doping, the bond population of Si5B is 1.8 times that of Si5Si3 and the structure fluctuates greatly. The migration of a single Li atom from V and B sites on the structure's surface to an orthotetrahedral site inside the structure is simulated. Simulation results show that with the increase of P doping concentration from 0 to 1.0 mol%, the Li diffusion rate is ordered as 0.5 mol% < 0 mol% < 1.0 mol%. Furthermore, the ab initio molecular dynamics method is used to simulate the diffusion of multiple Li atoms in P-doped Si(100)-7. When the simulation time is longer than 0.09 ps, the Li diffusion rate is ordered as 0.5 mol% < 0 mol% < 1.0 mol%. Doping Si(100) surface with P could effectively reduce the diffusion barrier for Li atoms in it.

Automated summary

The surface and lithium diffusion properties of Si(100) doped with B and P were studied using the first-principles plane wave pseudopotential method. The calculations showed a greater effect of B-doping compared to P-doping on Si(100)-7. The presence of P reduced the diffusion barrier for Li atoms, as observed in the simulation results of multiple Li atom diffusion.