System and method for creating linear and non-linear trenches in silicon and other crystalline materials with a router

• US 7,785,485 B2
• Filed: 09/17/2004
• Issued: 08/31/2010
• Est. Priority Date: 09/17/2003
• Status: Active Grant

• Current Assignee: Beaver-Visitec International, Inc (BVI Medical, Inc.)
• Original Assignee: Becton, Dickinson & Co
• Inventors: Daskal, Vadim M., Keenan, Joseph F., Hughes, James Joseph
• Primary Examiner(s): CULBERT, ROBERTS P
• Application Number:
  US10/943,229
• Publication Number:
  US 20070187874A1
• Time in Patent Office: 2,174 Days
• Field of Search: 216/53, 216/11, 216/2, 216/99, 216/101
• US Class Current: 216/53
• CPC Class Codes: A61B 17/32 Surgical cutting instruments A61B18/042 takes precedence; suture cutters A61B17/0467; instruments for ligaturing or cutting A61B17/128; instruments for rupturing the amniotic membrane A61B17/4208; specially adapted knives for eye surgery A61F9/0133
• CPC Class Codes: A61B 17/3211 Surgical scalpels, knives; Accessories therefor
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: B26B 21/58 characterised by the material

Abstract

A method for manufacturing blades for surgical and other uses from either a crystalline or polycrystalline material, preferably in the form of a wafer, comprises preparing the crystalline or polycrystalline wafers by mounting them and machining trenches into the wafers. The methods for machining the trenches, which form the bevel blade surfaces, include a diamond blade saw, laser system, ultrasonic machine, a hot forge press and a router. When a router is used, through-holes are drilled in the wafer to define the starting locations of the trenches. After the trenches are formed, the wafers are placed in an etchant solution which isotropically etches the wafers in a uniform manner, such that layers of crystalline or polycrystalline material are removed uniformly, producing single or double bevel blades, with each bevel having one or more facets. Nearly any bevel angle can be machined into the wafer which remains after etching. The resulting radii of the blade edges is 5-500 nm, which is the same caliber as a diamond edged blade, but manufactured at a fraction of the cost.

Claims

1. A method for manufacturing a cutting device from a wafer of crystalline material, comprising:

machining at least one blade profile in the wafer of crystalline material at least on a first side of the wafer with a router;

subsequently, isotropically etching the wafer of crystalline material to form at least one cutting device including at least one cutting edge comprising at least a portion of the at least one blade profile; and

singulating the etched crystalline material surgical blades.

13. The method according to claim 1, wherein the singulating step comprises:

dicing the machined wafer of crystalline material with a dicing blade.

14. The method according to claim 1, wherein the singulating step comprises:

dicing the machined wafer of crystalline material with a laser beam.

15. The method according to claim 14, wherein the laser beam is produced by an excimer laser or a laser waterjet.

16. The method according to claim 1, further comprising:

dicing the machined wafer of crystalline material profiles after machining the at least one blade profile in the form of single bevel cutting device and prior to the step of etching.

17. The method according to claim 16, wherein the dicing step comprises:

dicing the machined wafer of crystalline material with a dicing blade.

18. The method according to claim 16, wherein the dicing step comprises:

dicing the machined wafer of crystalline material with a laser beam.

19. The method according to claim 18, wherein the laser beam is produced by an excimer laser or a laser waterjet.

20. The method according to claim 1, further comprising:

machining at least one second blade profile in the wafer of crystalline material on a second side of the wafer of crystalline material prior to the step of etching with a router.

21. The method according to claim 20, wherein the step of machining comprises:

inserting a spinning router into at least one or more through holes;

moving the router to form a profile in the wafer of crystalline material; and

retracting the router after the profile in the wafer of crystalline material has been fully formed.

22. The method according to claim 20, further comprising:

coating the first side of the machined wafer of crystalline material.

23. The method according to claim 22, wherein the coating step comprises:

coating the first side of the machined wafer of crystalline material with a layer of material selected from the group consisting of silicon nitride, titanium nitride, aluminum titanium nitride, silicon dioxide, silicon carbide, titanium carbide, boron nitride, and diamond-like-crystals.

24. The method according to claim 20, further comprising:

dicing the machined wafer of crystalline material into separated machined double beveled blade profiles after machining the at least one second blade profile in the second side and prior to the step of etching.

25. The method according to claim 24, wherein the dicing step comprises:

dicing the machined wafer of crystalline material with a dicing blade.

26. The method according to claim 24, wherein the dicing step comprises:

dicing the machined wafer of crystalline material with a laser beam.

27. The method according to claim 26, wherein the laser beam is produced by an excimer laser or a laser waterjet.

28. The method according to claim 1, further comprising:

coating the first side of the wafer of crystalline material after the step of machining the wafer of crystalline material; and

mounting the wafer of crystalline material on its first side prior to the step of etching.

29. The method according to claim 28, wherein the coating step comprises:

coating the first side of the formed wafer of crystalline material with a layer of material selected from the group consisting of silicon nitride, titanium nitride, aluminum titanium nitride, silicon dioxide, silicon carbide, titanium carbide, boron nitride, and diamond-like-crystals.

30. The method according to claim 1, wherein the crystalline material comprises silicon.

31. The method according to claim 1, further comprising:

forming a conversion layer on the surface of the cutting device.

2. A method for manufacturing a cutting device from a wafer of crystalline material, comprising:

machining at least one blade profile in the wafer of crystalline material on its first side with a router; and

subsequently, etching the wafer of crystalline material to form at least one cutting device including at least one cutting edge comprising at least a portion of the at least one blade profile,

wherein the machining step comprises;

drilling at least one or more though-holes in the wafer of crystalline material;

inserting a spinning router into the at least one or more though holes;

moving the router to form a profile in the wafer of crystalline material; and

retracting the router after the profile in the wafer of crystalline material has been fully formed.

3. The method according to claim 2, wherein the drilling step comprises:

drilling at least one or more though-holes in the wafer of crystalline material with a drill.

4. The method according to claim 2, wherein the drilling step comprises:

drilling at least one or more through-holes in the wafer of crystalline material with a laser.

5. The method according to claim 2, wherein the drilling step comprises:

drilling at least one or more through-holes in the wafer of crystalline material with a laser waterjet.

6. The method according to claim 2, wherein the drilling step comprises:

drilling at least one or more through-holes in the wafer of crystalline material with an ultrasonic machine.

7. A method for manufacturing a cutting device from a wafer of crystalline material, comprising:

machining at least one blade profile in the wafer of crystalline material on its first side with a router; and

subsequently, etching the wafer of crystalline material to form at least one cutting device,

wherein the etching step comprises;

placing the wafer of crystalline material with at least one blade profile on a wafer boat;

immersing the wafer boat and wafer of crystalline material with at least one blade profile in an isotropic acid bath;

etching the crystalline material in a uniform manner such that the crystalline material is removed in a uniform manner on any exposed surface, whereby a sharp cutting device edge is etched in the shape of the at least one blade profile.

8. The method according to claim 7, wherein the isotropic acid bath comprises:

a mixture of hydrofluoric acid, nitric acid and acetic acid.

9. The method according to claim 7, wherein the isotropic acid bath comprises:

a mixture of hydrofluoric acid, nitric acid and water.

10. A method for manufacturing a cutting device from a wafer of crystalline material, comprising:

machining at least one blade profile in the wafer of crystalline material on its first side with a router; and

subsequently, etching the wafer of crystalline material to form at least one cutting device,

wherein the etching step comprises;

placing the wafer of crystalline material with at least one blade profile in a wafer boat;

spraying a spray etchant at the wafer boat and wafer of crystalline material with at least one blade profile;

etching the crystalline material in a uniform manner with the spray etchant such that the crystalline material is removed in a uniform manner on any exposed surface, whereby a sharp cutting device edge is etched in the shape of the at least one blade profile.

11. A method for manufacturing a cutting device from a wafer of crystalline material, comprising:

machining at least one blade profile in the wafer of crystalline material on its first side with a router; and

subsequently, etching the wafer of crystalline material to form at least one cutting device,

wherein the etching step comprises;

placing the wafer of crystalline material with at least one blade profile on a wafer boat;

immersing the wafer boat and wafer of crystalline material with at least one blade profile in an isotropic xenon difluoride, sulfur hexafluoride or similar fluorinated gas environment;

etching the crystalline material in a uniform manner with the isotropic xenon difluoride, sulfur hexafluoride or similar fluorinated gas such that the crystalline material is removed in a uniform manner on any exposed surface, whereby a sharp cutting device edge is etched in the shape of the at least one blade profile.

12. A method for manufacturing a cutting device from a wafer of crystalline material, comprising:

machining at least one blade profile in the wafer of crystalline material on its first side with a router; and

subsequently, etching the wafer of crystalline material to form at least one cutting device,

wherein the etching step comprises;

placing the wafer of crystalline material with at least one blade profile in a wafer boat;

immersing the wafer boat and wafer of crystalline material with at least one blade profile in an electrolytic bath;

etching the crystalline material in a uniform manner with the electrolytic bath such that the crystalline material is removed in a uniform manner on any exposed surface, whereby a sharp cutting device edge is etched in the shape of the at least one blade profile.

32. A method for manufacturing a cutting device from a crystalline material, comprising:

mounting a wafer of crystalline material on a mounting assembly;

pre-cutting the mounted wafer of crystalline material, such that a plurality of through hole fiducials are cut to assist in the machining step;

machining at least one blade profile in the wafer of crystalline material on its first side with a router;

subsequently, etching the wafer of crystalline material to form at least one cutting device including at least one cutting edge comprising at least a portion of the at least one blade profile;

singulating the at least one etched crystalline material cutting device; and

radiating the at least one singulated etched crystalline material cutting device with ultra-violet light, to separate them from the mounting assembly, in preparation for packaging for sale.

33. The method according to claim 32, wherein the machining step comprises:

inserting a spinning router into at least one or more through holes;

moving the router to form a profile in the wafer of crystalline material; and

retracting the router after the profile in the wafer of crystalline material has been fully formed.

34. The method according to claim 32, wherein the pre-cutting step comprises:

pre-cutting through hole fiducials in the mounted wafer of crystalline material with a laser beam.

35. The method according to claim 34, wherein the laser beam is produced by an excimer laser or a laser waterjet.

36. The method according to claim 32, wherein the pre-cutting step comprises:

pre-cutting through hole fiducials in the mounted wafer of crystalline material using a mechanical machining device.

37. The method according to claim 36, wherein the mechanical machining device comprises a drilling tool, ultrasonic machining tool or a mechanical grinding device.

38. The method according to claim 32, wherein the crystalline material comprises silicon.

39. The method according to claim 32, further comprising:

forming a conversion layer on the surface of the cutting device.

40. A method for manufacturing a cutting device from a crystalline material, comprising:

mounting a wafer of crystalline material on a mounting assembly;

pre-cutting the mounted wafer of crystalline material, such that a plurality slots are cut to assist in the machining step;

machining at least one blade profile in the wafer of crystalline material on its first side with a router;

subsequently, etching the wafer of crystalline material to form at least one cutting device including at least one cutting edge comprising at least a portion of the at least one blade profile;

singulating the at least one etched crystalline material cutting device; and

radiating the at least one singulated etched crystalline material cutting device with ultra-violet light, to separate them from the mounting assembly, in preparation for packaging for sale.

41. The method according to claim 40, wherein the machining step comprises:

inserting a spinning router into at least one or more through holes;

moving the router to form a profile in the wafer of crystalline material; and

retracting the router after the profile in the wafer of crystalline material has been fully formed.

42. The method according to claim 40, further comprising:

pre-cutting slots in the mounted wafer of crystalline material with a laser beam a distance away from the edge of the crystalline material; and

machining the at least one blade profile with a router that engages the crystalline wafer at the pre-cut slot.

43. The method according to claim 42, wherein the laser beam is produced by an excimer laser or a laser wateriet.

44. The method according to claim 40, further comprising:

pre-cutting slots in the mounted wafer of crystalline material with a mechanical machining device a distance away from the edge of the crystalline material; and

machining the at least one blade profile with a router that engages crystalline wafer at the pre-cut slot.

45. The method according to claim 44, wherein the mechanical machining device comprises a drilling tool, ultrasonic machining tool or a mechanical grinding device.

46. The method according to claim 40, wherein the crystalline material comprises silicon.

47. The method according to claim 40, further comprising:

forming a conversion layer on the surface of the cutting device.