Study of interfacial tensile and shear strength for Cu/Ta interface by molecular dynamic simulation

Abstract

Three-dimensional integration technology using TSV interconnections has emerged as a promising solution to improve the performance of microelectronic devices. It is necessary to study the effect of strain rate and work temperature on the interfacial strength of Cu/Ta interface for microelectronic devices reliability. In this work, to investigate the effect of the temperature and strain rate on the Cu/Ta interfacial properties, a series of large-scale molecular dynamic (MD) simulations were performed. The stress-strain curves and the deformation processes of Cu/Ta interface were obtained. The results showed that the interfacial tensile strength and interfacial shear strength of Cu(010)/Ta(010) interface are 5.56 GPa and 0.465 GPa, respectively, when the strain rate is 109/s and temperature is 300 K. And the location of failure for Cu/Ta interface is closer to the monocrystalline Cu parts. Then, the effects of strain rate and temperature on the interfacial tensile and shear strength were discussed, and the results indicated that the interfacial strength decrease with the decrease of strain rate from 109/s to 107/s. Similarly, the strongest correlation was seen to be between the interfacial strength and temperature, it can be seen that the interfacial tensile and shear strength decrease with increasing of the temperature.