Process for forming a ceramic layer

• US 8,663,337 B2
• Filed: 03/06/2012
• Issued: 03/04/2014
• Est. Priority Date: 06/18/2007
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Anderson, Jeffrey P., Popoola, Oludele O.
• Primary Examiner(s): Snow, Bruce E
• Assistant Examiner(s): DUKERT, BRIAN AINSLEY
• Application Number:
  US13/413,145
• Publication Number:
  US 20120165953A1
• Time in Patent Office: 728 Days
• Field of Search: 623/23.56
• US Class Current: 623/23.56
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2002/30929 having at least two superposed coatings
• CPC Class Codes: A61F 2310/00634 Coating made of zirconium oxide or hydroxides
• CPC Class Codes: A61L 27/306 Other specific inorganic materials not covered by A61L27/303 - A61L27/32
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/46 by ion beam produced by an external ion source
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

A process for forming a ceramic layer comprising a compound of a metal on a deposition surface of a workpiece comprises providing a reactive gas, selecting the amounts of a vapor of the metal and ions of the metal relative to each other, generating the metal vapor, and projecting an ion beam of the metal ions. The metal vapor, the metal ions, and the reactive gas form the ceramic layer with a desired structure. The process may include the step of controlling a deposition surface temperature. In one embodiment, the metal vapor comprises zirconium vapor and the ion beam comprises zirconium ions. The relative amounts of the zirconium vapor and the zirconium ions are selected to form a zirconia ceramic layer on the deposition surface. The zirconia may have multiple crystal phases that are formed according to a predetermined ratio.

Claims

1. An orthopedic implant comprising:

an orthopedic body having a deposition surface; and

a deposited ceramic layer supported by the deposition surface, the ceramic layer comprising two or more crystal phases comprising a monoclinic phase and a tetragonal phase having a volume ratio of greater than 0 to less than or equal to about 0.3, the two or more crystal phases sufficient to suppress phase transformation from the tetragonal phase to the monoclinic phase.

2. The implant of claim 1, wherein the deposited ceramic layer is formed on the deposition surface.

3. The implant of claim 1, wherein the ceramic layer comprises at least one polymorphic material.

4. The implant of claim 1, wherein the ceramic layer comprises SiO₂, ZrO₂, TiO₂, AS₂O₃, CaTiO₃, Al₂SiO, BN, ZnS, or FeS₂, or a combination thereof.

5. The implant of claim 1, wherein the ceramic layer comprises zirconia.

6. The implant of claim 1, wherein the ceramic layer comprises a zirconia ceramic layer having at least two of the two or more crystal phases.

7. The implant of claim 1, wherein the volume ratio of the monoclinic phase to the tetragonal phase is sufficient to suppress phase transformation from the tetragonal phase to the monoclinic phase.

8. The implant of claim 1, wherein the volume ratio of the monoclinic phase to the tetragonal phase suppresses phase transformation from the tetragonal phase to the monoclinic phase so as to not roughen due to a phase transformation during use in vivo.

9. The implant of claim 1, wherein the two or more crystal phases comprise a monoclinic zirconia having a plurality of oriented monoclinic crystals on the deposition surface, the oriented monoclinic crystals including more (11 1) monoclinic lattice planes than (111) monoclinic lattice planes.

10. The implant of claim 1, wherein the ceramic layer comprises zirconia comprising a monoclinic zirconia, a tetragonal zirconia, or a cubic zirconia, or a combination thereof.

11. The implant of claim 1, wherein the ceramic layer has a thickness of less than approximately 5 microns.

12. The implant of claim 1, wherein the ceramic layer is configured so as to not roughen due to a phase transformation during use in vivo.

13. The implant of claim 1, wherein an outer surface of the ceramic layer forms an articular surface.

14. The implant of claim 1, wherein the orthopedic body and the ceramic layer are configured for placement at an artificial joint.

15. The implant of claim 1, wherein the orthopedic body and the ceramic layer comprise a shape resembling a femoral hip ball or a femoral knee portion.

16. An artificial joint comprising:

an orthopedic body having a deposition surface; and

a deposited ceramic layer having a thickness of less than 5 microns and positioned on the deposition surface, the ceramic layer including at least a monoclinic zirconia phase and a tetragonal zirconia phase in a volume ratio of greater than 0 to less than or equal to about 0.3 and sufficient to suppress phase transformation from the tetragonal phase to the monoclinic phase, wherein the phase transformation suppression is in an amount sufficient to inhibit roughening of the ceramic layer during use in vivo;

wherein an outer surface of the ceramic layer is configured as an articular surface.

17. An artificial joint comprising:

an orthopedic body having a deposition surface; and

a deposited ceramic layer having a thickness of less than 5 microns and positioned on the deposition surface, the ceramic layer including at least a monoclinic zirconia phase having a plurality of oriented monoclinic crystals, the oriented monoclinic crystals comprising more (11 1) monoclinic lattice planes than (111) monoclinic lattice planes, wherein the orientation of the monoclinic crystals is sufficient to suppress phase transformation to the monoclinic phase, wherein the phase transformation suppression is in an amount sufficient to inhibit roughening of the ceramic layer during use in vivo;

wherein an outer surface of the ceramic layer is configured as an articular surface.