Formation of nanoscale surfaces for the atttachment of biological materials

Abstract

An inhomogeneous surface is formed on a substrate, such as an orthopedic implant or other surface upon which cell growth is desired, by depositing a discontinuous coating of atoms on the substrate and etching the substrate. The difference in etch rates between the coating and the substrate will produce structures in the nanometer scale. Deposition and etch conditions can be chosen to create structures of a specific size to preferentially bind to specific biological materials.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:

FIG. 1 is a cross-sectional view of a substrate having a discontinuous coating of atoms; and,

FIG. 2 is a cross-sectional view of the substrate of FIG. 1 after etching.

Claims

1. A method of forming an inhomogeneous surface comprising the steps of: depositing a discontinuous coating of atoms of a first substance on a substrate comprising a second substance, said first and second substances having first and second etch rates, respectively, wherein said first etch rate is different than said second etch rate; and,etching the substrate.

2. The method of claim 1 wherein said step of etching said substrate comprises etching said substrate via physical sputtering.

3. The method of claim 1 wherein said step of depositing said discontinuous coating comprises depositing via physical vapor deposition.

4. The method of claim 1 wherein said steps of depositing and etching are performed simultaneously.

5. The method of claim 1 wherein said discontinuous coating of atoms forms a plurality of clusters, each of said plurality of clusters having lateral dimensions from about ten nanometers to about one thousand nanometers.

6. The method of claim 1 wherein said inhomogeneous surface comprises a plurality of structures, each of said structures having heights from about ten nanometers to about ten thousand nanometers.

7. The method of claim 1 wherein said discontinuous coating is deposited on a mechanically rough portion of said substrate.

8. The method of claim 1 wherein said first etch rate is less than said second etch rate.

9. The method of claim 1 further comprising the step of: applying a voltage to said substrate, wherein applying said voltage causes a formation of structures on said substrate, each of said structures having a height of about one hundred nanometers to about ten thousand nanometers.

10. The method of claim 1 wherein said discontinuous coating of atoms forms a plurality of clusters and dimensions of said plurality of clusters are arranged to create a plurality of final structures that preferentially bind at least one biological structure having a specific size.

11. The method of claim 1 further comprising the step of: depositing a layer on said substrate, wherein said layer and said coating have a first chemical binding energy, said layer and said substrate have a second chemical binding energy, said first and second chemical binding energies are different, and said first and second chemical binding energies are arranged to alter nucleation characteristics of said coating.

12. The method of claim 1 wherein said substrate is a part of an orthopedic implant.

13. A method of preparing a substrate for cell attachment comprising the steps of: providing said substrate; and,depositing a coating of atoms on said substrate so that said atoms form clusters, each of said clusters having a size and a distance from other of said clusters.

14. The method of claim 13 wherein said size of each cluster and said distance from other of said clusters are chosen to preferentially bind at least one biological structure having a specific size.

15. The method of claim 13 further comprising the step of: changing a chemical binding energy between said substrate and said coating of said atoms.

16. A method of creating a surface for enhancing cell growth on said surface, said surface comprising a first substance, said method comprising the steps of: depositing a discontinuous coating of atoms of a second substance on said surface, wherein said first and second substances have first and second sputter yields, respectively, and said first and second sputter yields are different; andapplying a voltage to said surface to cause sputtering.

17. The method of claim 16 wherein said steps of depositing of said coating and applying of said voltage are performed simultaneously.

18. The method of claim 16 wherein said step of applying said voltage is performed after said step of depositing said coating.

19. The method of claim 16 wherein said surface is a part of an orthopedic implant.

20. A substrate arranged for cell attachment comprising: a surface; anda discontinuous coating of atoms on said surface, wherein said coating comprises a plurality of clusters of atoms, each of said plurality of clusters having lateral dimensions from about ten nanometers to about one thousand nanometers.