Dynamical branching during fluorination of the dimerized Si(100) surface: A molecular dynamics study

Collections of classical trajectories have been numerically generated for individual F2 molecules impinging at normal incidence on a Si(100) surface at 0 K dimerized in a p(2×1) pattern. A linear combination of two‐atom and three‐atom interaction functions represents the potential energy. Trajectories fall into four categories: (a) non‐reactive F2 rebound, (b) monofluorination at a surface dangling bond with energetic expulsion into the vacuum of the remaining F atom, (c) difluorination of a pair of dangling bonds, and (d) monofluorination with retention of the second F in a weakly bound Si–F⋅⋅⋅F surface complex. Surface patterns for difluorination, (c), indicate absence of surface diffusion during this mode of chemisorption. Increasing either the translational kinetic energy or the vibrational excitation of the incident F2 appears to enhance its surface reactivity.

[1]  C. W. Gear,et al.  Numerical initial value problem~ in ordinary differential eqttations , 1971 .

[2]  Gabor A. Somorjai,et al.  Chemistry in Two Dimensions: Surfaces , 1981 .

[3]  F. Mcfeely,et al.  Synchrotron photoemission investigation of the initial stages of fluorine attack on Si surfaces: Relative abundance of fluorosilyl species , 1984 .

[4]  H. F. Winters,et al.  Plasma‐assisted etching mechanisms: The implications of reaction probability and halogen coverage , 1985 .

[5]  Weber,et al.  Computer simulation of local order in condensed phases of silicon. , 1985, Physical review. B, Condensed matter.

[6]  Garrison,et al.  Dissociative valence force field potential for silicon. , 1986, Physical review. B, Condensed matter.

[7]  F. Stillinger,et al.  Molecular dynamics study of chemical reactivity in liquid sulfur , 1987 .

[8]  W. Goddard,et al.  Dissociation energetics of SiF systems of relevance to etching reactions , 1987 .

[9]  M. Baskes,et al.  Application of the embedded-atom method to covalent materials: A semiempirical potential for silicon. , 1987, Physical review letters.

[10]  Biswas,et al.  New classical models for silicon structural energies. , 1987, Physical review. B, Condensed matter.

[11]  Goddard,et al.  Reaction mechanism for fluorine etching of silicon. , 1987, Physical review. B, Condensed matter.

[12]  J. Tersoff,et al.  New empirical approach for the structure and energy of covalent systems. , 1988, Physical review. B, Condensed matter.

[13]  P. Avouris,et al.  Atom-resolved surface chemistry using scanning tunneling microscopy. , 1988, Physical review letters.

[14]  F. Stillinger,et al.  Molecular dynamics simulation for chemically reactive substances. Fluorine , 1988 .

[15]  F. Mcfeely,et al.  Fluorine-silicon reactions and the etching of crystalline silicon. , 1988 .

[16]  Pandey,et al.  New classical potential for accurate simulation of atomic processes in Si. , 1988, Physical review. B, Condensed matter.

[17]  Weber,et al.  Fluorination of the dimerized Si(100) surface studied by molecular-dynamics simulation. , 1989, Physical review letters.

[18]  Phillips,et al.  Surface and thermodynamic interatomic force fields for silicon clusters and bulk phases. , 1989, Physical review. B, Condensed matter.