Medical devices including metallic films and methods for making same

• US 20050197689A1
• Filed: 12/29/2004
• Published: 09/08/2005
• Est. Priority Date: 03/02/2004
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Molaei, Masoud
• Granted Patent: US 8,591,568 B2
• Time in Patent Office: Days
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/01 Filters implantable into blood vessels
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/823 Stents, different from stent-grafts, adapted to cover an aneurysm
• CPC Class Codes: A61F 2220/0041 using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material

Abstract

Medical devices, such as endoprostheses, and methods of making the devices are disclosed. The medical device can include a metallic film comprising nickel, titanium, and chromium, wherein a ratio of a weight of chromium of the metallic film to a combined weight of nickel, titanium, and chromium of the metallic film is at least 0.001. The metallic film can include a shape memory alloy.

Claims

1. An endoprosthesis, comprising:

a metallic film comprising an alloy comprising nickel, titanium, and chromium, the film having a thickness of about 50 μ

m or less.

2. The endoprosthesis of claim 1, wherein a ratio of the weight of chromium to the combined weight of nickel, titanium, and chromium is less than 0.0075.

3. The endoprosthesis of claim 2, wherein a ratio of the combined weight of nickel and titanium to a weight of the metallic film is at least 0.99.

4. The endoprosthesis of claim 1, wherein the chromium is uniformly distributed throughout the metallic film.

5. The endoprosthesis of claim 1, wherein the metallic film is a nickel, titanium, and chromium alloy.

6. The endoprosthesis of claim 1, wherein the metallic film is a vapor deposited film.

7. The endoprosthesis of claim 1, wherein the film comprises about 5×

10⁷ dislocations per cm² or more.

8. The endoprosthesis of claim 1 further including a stent, said film being attached to said stent.

9. A method of manufacturing an endoprosthesis, comprising:

forming a layer by depositing nickel and titanium on a substrate; and

irradiating at least some deposited nickel and titanium with particles having an energy of about 50 eV or more.

10. The method of claim 9, further comprising releasing the film from the substrate.

11. The method of claim 9, wherein the substrate is a stent body or portion thereof.

12. The method of claim 9, wherein irradiating comprises irradiating deposited nickel and titanium with particles having an energy of at least 500 keV.

13. The method of claim 9, wherein the depositing and the irradiating are combined and the particles having an energy of at least 50 eV comprise ions of nickel and titanium.

14. The method of claim 9, wherein the layer has a density N of dislocations per cm², the density N being at least 100 times larger than a density of dislocations in the absence of irradiating.

15. The method of claim 14, wherein the density N is at least 10¹⁰ dislocations per cm².

16. The method of claim 14, wherein the layer comprises an amount of chromium, a ratio of a weight of chromium of the layer to a combined weight of nickel, titanium, and chromium of the layer is at least 0.001, the ratio is 0.01 or less.

17. A method of manufacturing an endoprosthesis, comprising:

forming a film by depositing constituents of the film on a substrate, the constituents including nickel and titanium, the film having a density N of dislocations per cm²; and

increasing the density N of dislocations of at least a portion of the film by at least 100 times.

18. The method of claim 17, wherein the deposited nickel and titanium has a surface area and increasing the density N of locations comprises increasing the density N of dislocations of at least 20% of the surface area of the deposited nickel and titanium.

19. The method of claim 17, wherein increasing the density N of dislocations is performed before releasing the film from the substrate.

20. The method of claim 17, wherein increasing the density N comprises irradiating deposited nickel and titanium with particles having an energy of at least 50 eV.

21. A method of manufacturing an endoprosthesis, comprising:

depositing a film comprising nickel and titanium and having a thickness of at least 2 μ

m; and

heating the film by using optical radiation having an intensity sufficient to modify a crystalline structure of the film without rupturing the film.