Simulation of growth of Cu on Ag(001) at experimental deposition rates

The initial stages of growth of (001)Cu films on (001)Ag substrates have been investigated using the temperature-accelerated dynamics (TAD) simulation method. The acceleration provided by TAD made it possible to simulate the deposition of Cu on (001)Ag at 77 K using a deposition rate of 0.04 ML/s, which matched previously reported experiments. This simulation was achieved without a priori knowledge of the significant atomic processes. The results showed that the increased in-plane lattice parameter of the pseudomorphic Cu reduces the activation energy for the exchange mode of surface diffusion, allowing short-range terrace diffusion and the formation of compact Cu islands on the second film layer at 77 K. Some unexpected complex surface diffusion processes and off-lattice atomic configurations were also observed.

[1]  M. Kotrla,et al.  Step roughening effect on adatom diffusion , 1997 .

[2]  Laurent J. Lewis,et al.  Self-diffusion of adatoms, dimers, and vacancies on Cu(100) , 1997 .

[3]  D. Kolb,et al.  The initial stages of Cu electrodeposition on Ag(100): an in situ STM study , 1998 .

[4]  A. Voter,et al.  Classically exact overlayer dynamics: Diffusion of rhodium clusters on Rh(100). , 1986, Physical review. B, Condensed matter.

[5]  Georg Kresse,et al.  Norm-conserving and ultrasoft pseudopotentials for first-row and transition elements , 1994 .

[6]  Arthur F. Voter,et al.  Applying Accelerated Molecular Dynamics to Crystal Growth , 2001 .

[7]  Arthur F. Voter,et al.  Simulation Of The Layer-Growth Dynamics In Silver Films: Dynamics Of Adatom And Vacancy Clusters On Ag(100) , 1988, Optics & Photonics.

[8]  C. M. Gilmore,et al.  Molecular dynamics simulations of film-substrate interface mixing in the energetic deposition of fcc metals , 1996 .

[9]  M. Baskes,et al.  Embedded-atom method: Derivation and application to impurities, surfaces, and other defects in metals , 1984 .

[10]  Kunkel,et al.  Reentrant layer-by-layer growth during molecular-beam epitaxy of metal-on-metal substrates. , 1990, Physical review letters.

[11]  Foiles,et al.  Embedded-atom-method functions for the fcc metals Cu, Ag, Au, Ni, Pd, Pt, and their alloys. , 1986, Physical review. B, Condensed matter.

[12]  Z. Pan,et al.  Molecular-dynamics study of transient-diffusion mechanisms in low-temperature epitaxial growth , 1998 .

[13]  J. B. Adams,et al.  EAM study of surface self-diffusion of single adatoms of fcc metals Ni, Cu, Al, Ag, Au, Pd, and Pt , 1991 .

[14]  G. Kresse,et al.  Ab initio molecular dynamics for liquid metals. , 1993 .

[15]  G. Henkelman,et al.  Improved tangent estimate in the nudged elastic band method for finding minimum energy paths and saddle points , 2000 .

[16]  G. Henkelman,et al.  A climbing image nudged elastic band method for finding saddle points and minimum energy paths , 2000 .

[17]  Arthur F. Voter,et al.  Accurate Interatomic Potentials for Ni, Al and Ni3Al , 1986 .

[18]  M. Scheffler,et al.  Strained tetragonal states and bain paths in metals , 1996, mtrl-th/9609008.

[19]  R. Ferrando,et al.  Jumps and concerted moves in Cu, Ag, and Au(110) adatom self-diffusion , 1999 .

[20]  Kern,et al.  Strain driven fcc-bct phase transition of pseudomorphic Cu films on Pd(100). , 1995, Physical review letters.

[21]  A. Voter,et al.  Closing the Gap between Experiment and Theory , 2001 .

[22]  D. Kolb,et al.  The Initial Stages of Cu Deposition on Au(100) as Studied by in situ STM: The Epitaxial Growth of bcc Cu* , 1999 .

[23]  Distribution of occupation numbers in finite Fermi systems and role of interaction in chaos and thermalization , 1996, cond-mat/9610178.

[24]  Tian,et al.  Low-energy electron diffraction and photoemission study of epitaxial films of Cu on Ag{001} , 1991, Physical review. B, Condensed matter.

[25]  Cheng,et al.  Orientational ordering in mixed cyanide crystals: (NaCN)1-x(KCN)x. , 1991, Physical review. B, Condensed matter.

[26]  Q. Fang.  Theoretical treatment of the nonlinear anelastic internal friction peaks appearing in the cold-worked Al-based solid solutions , 1997 .

[27]  A. Voter,et al.  Extending the Time Scale in Atomistic Simulation of Materials Annual Re-views in Materials Research , 2002 .

[28]  Evans,et al.  Transition to Multilayer Kinetic Roughening for Metal (100) Homoepitaxy. , 1995, Physical review letters.

[29]  Arthur F. Voter,et al.  Structural stability and lattice defects in copper: Ab initio , tight-binding, and embedded-atom calculations , 2001 .

[30]  A. Voter,et al.  Normal-incidence steering effect in crystal growth: Ag/Ag(100) , 2001 .

[31]  Müller,et al.  Ion-beam-induced epitaxial vapor-phase growth: A molecular-dynamics study. , 1987, Physical review. B, Condensed matter.

[32]  Evans.  Factors mediating smoothness in epitaxial thin-film growth. , 1991, Physical review. B, Condensed matter.

[33]  Arthur F. Voter,et al.  Exploiting past visits or minimum-barrier knowledge to gain further boost in the temperature-accelerated dynamics method , 2002 .

[34]  M. Weinert,et al.  Thickness Induced Buckling of bcc Copper Films , 1999 .

[35]  D. Vanderbilt,et al.  Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. , 1990, Physical review. B, Condensed matter.

[36]  Evans,et al.  Low-temperature epitaxial growth of thin metal films. , 1990, Physical review. B, Condensed matter.

[37]  A. Voter.  Parallel replica method for dynamics of infrequent events , 1998 .

[38]  Li,et al.  Epitaxial growth of a metastable modification of copper with body-centered-cubic structure. , 1987, Physical review. B, Condensed matter.

[39]  M. Bartelt,et al.  Temperature dependence of kinetic roughening during metal(100) homoepitaxy : transition between 'mounding' and smooth growth , 1999 .

[40]  A. Voter,et al.  Closing the gap between experiment and theory: crystal growth by temperature accelerated dynamics. , 2001, Physical review letters.

[41]  A. Voter,et al.  Temperature-accelerated dynamics for simulation of infrequent events , 2000 .

[42]  Jacob,et al.  Reflection high-energy electron diffraction (RHEED) oscillations at 77 K. , 1989, Physical review letters.

[43]  David Chandler,et al.  Statistical mechanics of isomerization dynamics in liquids and the transition state approximation , 1978 .

[44]  G. Vineyard.  Frequency factors and isotope effects in solid state rate processes , 1957 .