Computer simulation for estimation of mechanical and thermal properties of AIN

Ab initio simulations have been performed to estimate the thermal conductivity of AlN with and without lattice imperfections and the strength properties of AlN and Al/AlN composite. Two types of simulation procedures were used, i.e. (1) ab initio molecular dynamics simulation (MD) based on local electron density and pseudopotential approximations, and (2) a usual MD using a proper functional form of the interatomic potential which is set up in advance by ab initio MO-calculation. It is shown for the simulation results that the thermal conductivity of AlN depends strongly on lattice imperfection and fracture of Al/AlN interface is brought about by outflow of the charge from Al- to AlN-sides.