Methods of fabricating complex blade geometries from silicon wafers and strengthening blade geometries

Abstract

Ophthalmic surgical blades are manufactured from either a single crystal or poly-crystalline material, preferably in the form of a wafer. The method comprises preparing the single crystal or poly-crystalline wafers by mounting them and etching trenches into the wafers using one of several processes. 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. Other processes include wet etching (isotropic and anisotropic) and dry etching (isotropic and anisotropic, including reactive ion etching), and combinations of these etching steps. The wafers are then placed in an etchant solution which isotropically etches the wafers in a uniform manner, such that layers of crystalline or poly-crystalline material are removed uniformly, producing single, double or multiple bevel blades. Nearly any angle can be machined into the wafer, and the machined angle 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. A range of radii may be 30 to 60 nm, with a specific implementation being about 40 nm. The blade profile may have an angle of, for example, about 60 DEG. The ophthalmic surgical blades can be used for cataract and refractive surgical procedures, as well as microsurgical, biological and non-medical, non-biological purposes. Surgical and non-surgical blades and mechanical devices manufactured as described herein can also exhibit substantially smoother surfaces than metal blades.

Description

[0001] Documents included by reference [0002] This application contains subject matter related to five U.S. Provisional Patent Applications: Serial No. 60 / 362,999, filed March 11, 2002, entitled "System and Method for the Manufacture of Surgical Blades," 60 / 430,322, entitled "System and Method for the Manufacture of Surgical Blades", and 60 / 503,458, filed September 17, 2003, entitled "System and Method for Creating Linear and Non-Linear Trenches in Silicon and Other Crystalline Materials with a Router", Serial No. 60 / 503,459, filed September 17, 2003, entitled "Silicon Blades for Surgical and Non-Surgical Use", Serial No. 60 / 566,397, filed April 30, 2004, entitled " Silicon Surgical Blades and Method of Manufacture", and U.S. Nonprovisional Patent Application Serial No. 10 / 383,573, filed March 10, 2003, entitled "System and Method for the Manufacture of Surgical Blades", all of the preceding provisional and The entirety of what is expressed in the non-provisional patent appl...

AI Technical Summary

Problems solved by technology

This is both inefficient and ineffective for mass production of high-quality, defect-free ophthalmic blades

Inefficient because steps are added to the manufacturing process

[0010] This approach also inherently has significant cutting edge geometry limitations

The bevels produced by this method are limited to an inefficient 45° for single bevel inserts and an impractical 90° for double bevel inserts

Furthermore, the method severely limits the width of the bevels to a maximum of twice the thickness of the wafer for single bevel inserts and half the thickness of the wafer for dual bevel inserts

These geometries result in poor cutting tools as evidenced by little adoption in the ophthalmic community

Images