Atomistic simulations of hard and soft films under nanoindentation

Abstract Three-dimensional molecular dynamics (MD) simulation is used to investigate the atomistic mechanism of nanoindentation process under different indentation loads, temperatures and loading rates. Diamond and gold were selected as the hard and soft materials. The results showed that when the loads and the loading rates increased, both Young's modulus and the hardness of the films were increased. When the nanoindentation was operating under high temperatures, the thermal softness behavior took place causing a reduction in Young's modulus. The hardness for diamond and gold films was approximately 90–100 GPa and 3–5 GPa, while the present MD analysis for diamond and gold films was found to be 84–107 GPa and 5–7 GPa, respectively. Young's modulus for the diamond and gold films were approximately 1002–1100 GPa and 110–130 GPa, while the present MD analysis for diamond and gold films was found to be 1199–1862 GPa and 78–129 GPa, respectively. Both Young's modulus and the hardness were slightly higher than those in the experiments. The discrepancy between the MD analysis and the experiments will be further discussed in this paper.

[1]  Jee-Gong Chang,et al.  Molecular dynamics simulation of nano-lithography process using atomic force microscopy , 2002 .

[2]  Cheng-I Weng,et al.  Three-dimensional molecular dynamics analysis of processing using a pin tool on the atomic scale , 2000 .

[3]  J. M. Haile,et al.  Molecular dynamics simulation : elementary methods / J.M. Haile , 1992 .

[4]  B. Bhushan,et al.  Fatigue studies of nanoscale structures for MEMS/NEMS applications using nanoindentation techniques , 2003 .

[5]  Uzi Landman,et al.  Atomistic Mechanisms and Dynamics of Adhesion, Nanoindentation, and Fracture , 1990, Science.

[6]  J. Tersoff,et al.  Modeling solid-state chemistry: Interatomic potentials for multicomponent systems. , 1989, Physical review. B, Condensed matter.

[7]  G. Pharr,et al.  An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments , 1992 .

[8]  Jee-Gong Chang,et al.  Molecular dynamics analysis of temperature effects on nanoindentation measurement , 2003 .

[9]  Te-Hua Fang,et al.  Nanoindentation characteristics on polycarbonate polymer film , 2004, Microelectron. J..

[10]  D. Srivastava,et al.  Nanoscale etching and indentation of a silicon(001) surface with carbon nanotube tips , 1999 .

[11]  Bharat Bhushan,et al.  Measurement of fracture toughness of ultra-thin amorphous carbon films , 1998 .

[12]  Bharat Bhushan,et al.  NANOINDENTATION HARDNESS MEASUREMENTS USING ATOMIC FORCE MICROSCOPY , 1994 .

[13]  Yu. A. Burenkov,et al.  Softening of the elastic modulus in submicrocrystalline copper , 1995 .

[14]  Liangchi Zhang,et al.  Molecular dynamics simulation of phase transformations in silicon monocrystals due to nano-indentation , 2000 .

[15]  Te-Hua Fang,et al.  Nanomechanical properties of copper thin films on different substrates using the nanoindentation technique , 2003 .

[16]  Properties of the liquid-vapour interface of fcc metals calculated using the tight-binding potential , 1997 .

[17]  Yoshitada Isono,et al.  Molecular Dynamics Simulations of Atomic Scale Indentation and Cutting Process with Atomic Force Microscope , 1999 .