Semiquantitative subplantation model for low energy ion interactions with solid surfaces. III. Ion beam homoepitaxy of Si

Abstract

The semiquantitative subplantation model developed in article I [K. J. Boyd, D. Marton, J. W. Rabalais, S. Uhlmann, and Th. Frauenheim, J. Vac. Sci. Technol. A 16, 444 (1998)] is used to describe the homoepitaxial growth of Si{100} films by low energy ion beam deposition. The model successfully describes the epitaxial quality of films grown at a variety of ion energies and substrate temperatures. Density functional molecular dynamics simulations are used to calculate threshold energies and cross sections for penetration of ions into the target lattice. These calculated values, used in conjunction with the model, yield good agreement with recently published experimental data for homoepitaxy by direct deposition of low energy Si+ ions. The model also provides a simple qualitative explanation of the limiting epitaxial thickness in molecular beam epitaxy and the success of epitaxial Si deposition by other hyperthermal particle methods. New insight into the atomic-level behavior of epitaxial film growth from hyperthermal particles is obtained from these applications.

The effect of ion-surface and ion-bulk interactions during hydrogenated amorphous silicon deposition

“…Furthermore, it is speculated that ions below a certain threshold E p can penetrate below the surface as an interstitial without creating any damage. 38,42 For ions bombarding silicon it is estimated that E p ϳ 7 eV. 42 If the ion has enough energy it can displace atoms in the lattice, in which Si surface and bulk displacement ͑some monolayers underneath the surface͒ can be distinguished.…”

“…38,42 For ions bombarding silicon it is estimated that E p ϳ 7 eV. 42 If the ion has enough energy it can displace atoms in the lattice, in which Si surface and bulk displacement ͑some monolayers underneath the surface͒ can be distinguished. The threshold energy for surface Si displacement is roughly 18 eV, whereas the threshold energy for the more bonded bulk Si is higher, i.e., roughly 40 eV.…”

Thin Film Synthesis by Energetic Condensation

“…In this energy range, incident ions and atoms can dislodge adsorbed species and penetrate the substrate surface. This may lead to the film growing beneath the surface (12)(13)(14), in a process that became known as sub-plantation. Sub-plantation has been used to describe formation of several materials, in particular non-hydrogenated diamondlike carbon films (DLC).…”