KR20070005725A - Methods of fabricating complex blade geometries from silicon wafers and strengthening blade geometries - Google Patents

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. 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. ® KIPO & WIPO 2007

Description

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

The present invention relates to ophthalmic and other types of surgical and non-surgical blades and mechanical devices. More specifically, ophthalmic microsurgical and nonsurgical blades and mechanical devices made of monocrystalline silicon and other monocrystalline or polycrystalline materials, and methods of manufacturing and strengthening the above-mentioned mechanical devices, surgical and nonsurgical blades It is about.

(Related by reference)

The present specification discloses a `` system and method for manufacturing surgical blades '' of serial number 60 / 362,999, filed March 11, 2002, and ″ operating blades of serial number 60 / 430,322, filed December 3, 2002. Manufacturing Systems and Methods ″, System and Method for Forming Linear and Non-Linear Trenchs in Silicon and Other Crystals Using a ″ Router of Serial No. 60 / 503,458, filed Sep. 17, 2003 ″, 2003 `` Surgical and non-surgical silicon blades '' filed September 17, 2004, serial number 60 / 566,397, filed April 30, 2004, and `` silicon surgical blades and methods of making the same. '' Five US patent provisional applications and US Patent Application No. 10 / 383,573, filed on March 10, 2003, of US Patent Application, entitled "System and Method for Manufacturing Surgical Blades." And the whole contents of the specification of the patent application are shown that in connection with the present specification by reference.

Existing surgical blades are manufactured by several different methods, each with its own advantages and disadvantages. The most common method of manufacturing is the mechanical polishing of stainless steel. The blades are then polished or electrochemically polished by various other methods, such as ultrasonic slurrying, mechanical abrasives and lapping, in order to have sharp edges. The advantages of these methods are that mass production of disposable blades is possible and economical. The biggest drawback of these processes is that the blade quality is variable, which limits the uniformity of the sharpness. This is mainly due to the inherent limitations of the process itself. The blade radius of the blade may range from 30 nm to 1000 nm.

A relatively new blade manufacturing method is coining instead of grinding stainless steel. As a result, the blade is electrochemically polished to form a sharp blade. This process is economical compared to the grinding method. In addition, this method is able to produce sharper blades more uniformly. A disadvantage of this method is that the uniformity of the sharpness is still lower than that of the diamond blade manufacturing method. At present, metal blades are mainly used for the surgery of soft tissues, due to the cost and improved quality of the disposable use of the metal blades.

Diamond blades are the highest criterion for sharpness in many surgical tool markets, especially in the ophthalmic surgical market. Diamond blades can cut soft tissue neatly with minimal tissue resistance. In addition, the sharpness is uniform in subsequent cuts, so the use of diamond blades is required. Many blades use diamond blades because metal blades have a lower degree of sharpness than diamond blades, and the sharpness changes. In order to achieve an elaborately sharp and uniform blade radius, lapping methods are used to make diamond blades. The resulting blade edge radii range from 5 nm to 30 nm. The disadvantage of this method is that the manufacturing process is slow, and as a direct result, the cost of manufacturing diamond blades ranges from $ 500 to $ 5000. Thus, such blades are sold for reuse. In order to achieve the same sharpness at low cost, less rigid materials such as ruby and sapphire are currently used. However, even though they are less expensive than diamonds, surgical quality blades formed from ruby and / or sapphire have a relatively high manufacturing cost ranging from $ 50 to $ 500 and the blades remain only about 200 surgical operations. There is this. Such blades are therefore sold for reuse or for limited reuse.

Several methods of manufacturing surgical blades using silicone have been proposed. However, in one form or the other, such methods are limited only in terms of being able to manufacture the blades in various shapes and at a disposable cost. Many silicon blade patents are based on anisotropic etching of silicon. An anisotropic etching method is a highly directional etching with different etching rates in different directions. This method can form a sharp cutting blade. However, due to the principle of this method, the shape of the manufacturable blade and the bevel angles inherent therein are limited. Wet bulk anisotropic etching methods are, for example, potassium hydroxide (KOH), ethylene-diamine / pyrcatechol (EDP), and trimethyl-2-hydroxyethylammonium hydroxide (trimethyl-). 2-hydroxethylammonium hydroxide (TMAH) baths are used to etch along specific crystal planes to form sharp blades. This crystal plane is typically the (111) plane in the silicon <100> direction and has an angle of 54.7 ° from the surface of the silicon wafers. Accordingly, the blade has an inherent oblique angle of 54.7 °, which is too blunt and cannot be used medically as most surgical instruments. If this method is used to form double oblique blades with an intrinsic oblique angle of 109.4 °, the disadvantage is further highlighted. This method also limits the blade profiles that can be manufactured. The etching faces are aligned at an angle of 54.7 ° with respect to each other on the wafer. Thus, only blades with rectangular profiles can be manufactured.

In methods of manufacturing surgical and non-surgical blades and other mechanisms from silicone, which are described in detail below, brittle silicone materials may be mechanically damaged during one or more machining steps. Can be. Cracks, chips, scratches, and sharp blades all serve as starting points for cracking brittle materials. When a load or stress is applied to these starting points, catastrophic failure of the mechanical devices begins at that starting point.

Another known method of forming sharp blades on blades formed from wafers is to use a photomask with isotropic wet or dry etching to etch the wafer to form the contour and cutting blade of the ophthalmic blade. In this method, the entire circumference of the blade is etched to form a sharp blade. Such thru-etching is only possible while the etch mask is properly positioned. The mask roughly defines where the cutting blades are created. The mask is then removed and the blades float freely as their carriers dissolve (an additional die level cleaning step is required). This is inefficient and ineffective in producing high quality and defect free ophthalmic blades in large quantities. That is, there are steps added to the manufacturing method, which is inefficient.

In addition, due to the inherent properties of this method, the appearance of the cutting blade is very limited. The slant formed by this method is 45 ° which is not sufficient for a single slanted blade and is limited to 90 ° unrealistic for a double slanted blade. In addition, the width of the inclined plane is very limited by the above method, so as to maximize the thickness of the wafer for a single inclined blade, and 1.5 times the wafer thickness for a double inclined blade. These contours are of low quality as cutting tools, which are difficult to use in ophthalmic systems.

Therefore, there is a need for a method of manufacturing blades that can eliminate the drawbacks of the methods described above. The system and method according to the invention can produce blades with the sharpness of diamond blades as a disposable manufacturing cost of stainless steel methods. In addition, the system and method according to the present invention enable strict production control and mass production for the manufacture of blades. In addition, the systems and methods according to the present invention can produce surgical and various other types of blades having both linear or nonlinear blade oblique surfaces. In addition, the systems and methods according to the present invention can eliminate mechanical damage caused in silicon crystals by making blades (surgical or non-surgical) or other mechanical devices by the methods described herein. .

In order to overcome the above disadvantages and to realize many advantages, the present invention provides a manufacturing system and method for manufacturing surgical blades from crystalline or polycrystalline materials such as silicon, using various means for trenches in a crystalline or polycrystalline wafer. By providing a machining method to produce the desired bevel angle or blade shape. The machined crystal or polycrystalline wafers are then subjected to an isotropic etching solution which in turn uniformly removes the molecular layer of the wafer material, in order to form a cutting blade of uniform radius and of sufficient quality for soft tissue surgery. Is immersed. The system and method of the present invention provide a very inexpensive means for producing high quality surgical blades.

Accordingly, one object of the present invention is to provide a method for manufacturing a surgical blade, the method comprising the steps of mounting a silicon or other crystalline or polycrystalline wafer on a mounting assembly, to form a linear or nonlinear trench. machining one or more trenches on the first side of the crystalline or polycrystalline wafer using a router; etching the first side of the crystalline or polycrystalline wafer to form one or more surgical blades And singulating the surgical blades, and assembling the surgical blades.

Another object of the present invention is to provide a method for manufacturing a surgical blade, the method comprising: mounting a crystalline or polycrystalline wafer on a mounting assembly, using the router to form linear or nonlinear trenches, or Machining one or more trenches on the first side of the polycrystalline wafer, forming and coating a coating layer on the first side of the crystalline or polycrystalline wafer, mounting of the crystalline or polycrystalline wafer from the mounting assembly Dismounting, remounting a first side of a crystalline or polycrystalline wafer on the mounting assembly, machining a second side of the crystalline or polycrystalline wafer, one or more surgical The crystal or die to form blades Etching the second side of the crystalline wafer, singulating the surgical blades, and assembling the surgical blades.

It is yet another object of the present invention to provide a method of manufacturing a surgical blade, the method comprising: mounting a crystalline or polycrystalline wafer on a mounting assembly, using the router to form linear or nonlinear trenches; Or machining one or more trenches on the first side of the polycrystalline wafer, removing the mounting of the crystalline or polycrystalline wafer from the mounting assembly, removing the first side of the crystalline or polycrystalline wafer on the mounting assembly. Remounting, machining a second side of the crystalline or polycrystalline wafer using a router to form linear or nonlinear trenches, and forming the one or more surgical blades to form the one or more surgical blades. Expression of the second side Agitating, converting the crystalline or polycrystalline layer to form a hardened surface, singulating the surgical blades, and assembling the surgical blades.

Another object of the present invention is to provide ophthalmic, microsurgical, heart, eye, ear, brain, orthopedic and plastic surgery and biological use as well as a variety of non-medical uses, prepared by the methods disclosed herein. To provide several exemplary embodiments of a surgical blade for.

It is yet another object of the present invention to provide a system for increasing the strength of mechanical devices and surgical and non-surgical blades made from single or polycrystalline materials comprising silicon, by one or more processes disclosed herein; To provide a way.

It is therefore an object of the present invention to provide a method based on isotropic and anisotropic etching methods which have all the advantages disclosed herein without any disadvantages of the prior art. This method allows composite blade contours to form, including but not limited to, various single and double inclined surfaces, such as, for example, slit knives, trapezoidal knives, chisel knives, and the like. According to various embodiments of the present invention, the aforementioned methods of manufacturing blades using the isotropic etching process are limited by the availability of precise mechanical methods for forming V-grooves that ultimately become cutting blades of the blades. Limited. The method according to one embodiment of the invention forms V-grooves without applying any mechanical stresses to the wafer. Using a combination of photomask formation, wet etching (isotropic and anisotropic), and dry etching (including isotropic and anisotropic, and reactive ion etching), the V-grooves are of an unlimited number of two-dimensional contours. Can be formed, and can also be formed by controlling the pre-formed bevel angle. Once the V-grooves (or trenches) are formed first, the trenches are then subjected to a wet isotropic etching process without the use of a mask, as disclosed herein. This results in a final blade contour and very sharp cutting blades.

DETAILED DESCRIPTION Hereinafter, with reference to the detailed description of the preferred embodiments in conjunction with the accompanying drawings, it will be described to best understand the novel features and advantages of the present invention.

1 is a flow chart of a method for manufacturing a double bevel surgical blade from silicon in accordance with a first embodiment of the present invention;

2 is a flow chart of a method for manufacturing a single bevel surgical blade from silicon in accordance with a second embodiment of the present invention;

3 is a flow chart of another method for manufacturing a single oblique surgical blade from silicon in accordance with a third embodiment of the present invention;

4 is a top view of a silicon wafer mounted on a mounting assembly;

5 is a side view of a silicon wafer mounted on a mounting assembly using tape;

6 illustrates a method of using a laser water-jet to pre-cut the silicon wafer to assist in machining trenches in the silicon wafer according to one embodiment of the present invention;

7A-7D illustrate the shapes of a dicing saw blade used for the machining of trenches in a silicon wafer according to one embodiment of the present invention;

8 illustrates the operation of a dicing saw blade through a silicon wafer mounted on a back support according to one embodiment of the present invention;

8A-8C illustrate the use of slots when machining trenches in a silicon wafer using a dicing saw blade according to one embodiment of the present invention;

9 is a cross-sectional view showing a dicing saw blade for machining trenches in a tape mounted silicon wafer in accordance with one embodiment of the present invention;

10A and 10B respectively show a silicone surgical blade comprising a single oblique cutting blade formed by an embodiment of the present invention and a silicone surgical blade comprising a double oblique cutting blade;

11 is a block diagram of a laser system used for the machining of trenches in a silicon wafer in accordance with one embodiment of the present invention;

12 is a block diagram of an ultrasonic machining system used for the machining of trenches in a silicon wafer in accordance with one embodiment of the present invention;

13 is a block diagram of a hot forging system used to form trenches in a silicon wafer according to one embodiment of the present invention;

14 is a cross-sectional view illustrating a silicon wafer having a single machined trench including a coating layer formed on a machined side according to one embodiment of the present invention;

15 is a cross-sectional view illustrating a dicing saw blade for machining a second trench in a silicon wafer mounted using tape in accordance with one embodiment of the present invention;

16 illustrates a cross-section of a silicon wafer with trenches machined on both sides in accordance with one embodiment of the present invention;

17A and 17B illustrate an isotropic etching process performed on a silicon wafer including trenches machined on both sides in accordance with one embodiment of the present invention;

18A and 18B illustrate an isotropic etching process performed on a silicon wafer including trenches machined on both sides and a coating layer on one side according to one embodiment of the present invention;

FIG. 19 shows the resulting cutting blade of a double comb silicon surgical blade with a coating layer on one side made by one embodiment of the present invention; FIG.

20A-20G show various examples of surgical blades manufacturable by the method of the present invention;

21A and 21B show the side of the blade edge of the silicon surgical blade and the side of the blade edge of the stainless steel surgical blade produced at embodiments of the present invention at 5,000 magnification, respectively;

22A and 22B show, respectively, at 10,000 magnifications the top surface of the blade blade of the silicon surgical blade and the blade blade of the stainless steel surgical blade manufactured according to embodiments of the present invention;

23A and 23B illustrate an isotropic etching process performed on a silicon wafer comprising trenches machined on one side and a coating layer on opposite sides by another embodiment of the present invention;

24 shows a handle of a surgical blade and a post-slot assembly made in accordance with embodiments of the present invention;

25A and 25B show profile perspective views of blade blades formed of crystalline material and blade blades formed of crystalline material including a layer conversion process in accordance with embodiments of the present invention;

26-29 illustrate steps of using a router to machine linear or nonlinear trenches in a crystalline material in accordance with one embodiment of the present invention;

30 is a flowchart of a method for forming linear or nonlinear trenches in a crystalline material according to one embodiment of the present invention;

31A-31C illustrate a double oblique multiple facet blade made in accordance with embodiments of the present invention;

32A-32C show various double comb face blades manufactured by embodiments of the present invention;

33A-33D show several examples of surgical blades that can be used for ophthalmology and other microsurgeries made by the methods of the present invention;

34A-34C show various manufacturing parameters of a surgical blade made in accordance with embodiments of the present invention;

35A and 35B show additional manufacturing parameters of a surgical blade made in accordance with embodiments of the present invention;

FIG. 36 shows a comparison of the range of blade radii of blades made of metal and surgical blades made of silicon by embodiments of the present invention; FIG.

37 compares the ranges of the surface roughness of the blade radii of metal blades and surgical blades made of silicon by embodiments of the present invention;

38 is a flowchart of a method for manufacturing a silicon surgical blade according to a fourth embodiment of the present invention;

39-43 show silicon wafers processed by the method of manufacturing the silicon surgical blades shown in FIG. 38;

44-52 show etching results of various depths of sample coupons cut by diamond saws and lasers in relation to the smoothness of the surfaces;

53A-53C show the peak stab force, pressure required to cause a wound gape of diamond blades, metal blades, and silicon blades manufactured by embodiments of the present invention; And comparison results for the force required to penetrate the test medium;

54 shows a cross section of a wafer comprising a layer of photoresist material (photoresist) used in the manufacture of surgical blades in accordance with an embodiment of the present invention;

55A shows a cross-section of the silicon wafer of FIG. 55 including a first patterned photomask positioned on a photoresist layer exposed to ultraviolet light, and FIG. 55B shows that exposure to ultraviolet light is complete and photoresist is developed. And a cross section of the silicon wafer of FIG. 55A after the first patterned photomask has been removed;

56A and 56B show an example of placement of a second patterned photomask and exposure to ultraviolet light, similar to those shown in FIGS. 55A and 55B;

FIG. 57A shows a cross-section of the silicon wafer of FIG. 55B after partial anisotropic etching is performed by one embodiment of the present invention, and FIG. 57B shows an isotropic etching process by an anisotropic etching process according to another embodiment of the present invention. The cross-section of the silicon wafer of FIG. 56B after in-situ conversion is shown.

FIG. 58 illustrates a cross-section of the silicon wafer of FIG. 56B after partial anisotropic wet etching is performed by another embodiment of the present invention; FIG.

59 shows a cross-section of the wafer of FIG. 57B with the developed photoresist layer removed;

FIG. 60 shows a cross section of the wafer of FIG. 58 with the patterned photoresist layer removed;

FIG. 61 shows a cross section of a wafer including two partial etching layers similar to the etching process shown in FIGS. 57A and 57B to form a double oblique blade;

FIG. 62 shows a cross section of a wafer including two partial etch layers similar to the etch layer shown in FIG. 58 to form another type of double oblique blade; And

63 is a flowchart illustrating a method of manufacturing silicon surgical blades according to an embodiment of the present invention.

Various aspects of the preferred embodiments are described with reference to the drawings, wherein like reference numerals refer to like elements. The best embodiments provided below for implementing the present invention are not intended to limit the present invention, but merely for the purpose of illustrating the general principles of the present invention.

The present invention provides a system and method for manufacturing surgical blades for use in cutting soft tissue. Although the preferred embodiment describes a surgical blade, various cutting devices can be manufactured by the methods described in detail below. Thus, although described herein in the context of `` surgical blades '' as a whole, numerous other aspects of cutting devices, such as medical razors, lancets, hypodermic needles It will be apparent to those skilled in the art that the manufacture of hypopodermic needles, sample collection cannula and other medical sharps is possible. In addition, blades made by the systems and methods of the present invention can be used for other non-medical use, such as shaving and laboratory use (ie, tissue sampling). In addition, the following description refers to ophthalmic use as a whole, but includes, but is not necessarily limited to, many other types of medical use of eye, heart, ear, brain, plastic surgery, and orthopedic surgery.

Although known to those skilled in the art, terms of single bevel, double bevel, and facets should be defined. By a single inclined plane is meant one inclined plane on the blade that is the same area as the primary surface of the blade, resulting in a sharp cutting blade. In this regard, reference is made to FIG. 10A, which will be described below by way of example. By double inclined plane is meant two inclined planes on the blade which are areas that result in a sharp cutting blade on a surface substantially the same as the centerline as a whole, as shown in FIGS. 10B, 20A and 31C. The facet is a flat blade on the oblique side. On any blade, there may be one, two, or multiple facets per bevel on one side. Thus, on any one blade, there may be compound sharp blades (or, ie, a complex set of oblique faces, and each oblique face may have a single or complex facets).

34A-34C are additional views of surgical blade 340 manufactured according to one embodiment of the present invention. In Figure 34A, various parameters of the surgical blades are shown. For example, the side cut length, the length from tip to shoulder, and the profile angle are shown. The values of each parameter may vary depending on the design of the blade and the desired usage. However, due to the advantages of the method of manufacturing the surgical and non-surgical blades (as described below), the profile angles of the surgical blades produced by embodiments of the present invention are generally smaller than when contacted. Can be made. One embodiment of the present invention may yield profile angles of about 60 ° for a particular blade profile, but this is for illustrative purposes only and is not limited thereto. 34B and 34C show the additional parameters described above.

Additional industrial terms and parameters known to those skilled in the art are the blade radius of the blade. The ″ cutting radius ″ or ″ blade radius ″ is the radius of the sharp blade cutting the skin, eyes (for ophthalmic use) or other substances / materials. If, for example, the surgeon uses the blade to cut or incise the patient's eye, it is very important that it is not necessary that the blade be as sharp as possible. 35A and 35B show the blade radius of a surgical blade made in accordance with an embodiment of the present invention. FIG. 35B shows a cut along the line A-A of the blade 350 of FIG. 35A. Blades (surgical or non-surgical) manufactured by embodiments of the present invention described below may have a blade radius in the range of about 30 nm to about 60 nm, and in one embodiment of the present invention about 40 It has a blade radius of nm. Tables 1 and 2 collect measurements of the blade radii of metal blades and the blade radii of silicon blades manufactured by embodiments of the invention described below. The data are summarized in FIG. 36 by a first bend 362 showing the range of blade radii of a blade made by embodiments of the invention described herein, and in the second bend 364. Thereby very small compared to the range of blade radii of the metal blades shown in FIG. 36. Small blade radii form sharper blades.

Edge Radius-Metal Blades blade Measure number Radius Average Standard Deviation ACC1 One 784 Average radius of all metal blades 2 1220 1296 nm 3 975 4 1180 Standard Deviation of All Metal Blades 5 1345 1101 222 269 nm ACC2 One 1190 2 1430 3 1180 4 1170 5 1740 1342 248 ACC3 One 1600 2 1250 3 905 4 940 5 1220 1183 281 ACC4 One 1430 2 1290 3 1380 4 1460 5 1670 1446 141 ACC5 One 1600 2 1150 3 923 4 992 5 1110 1155 265 ACC6 One 1530 2 1240 3 1810 4 1670 5 1500 1550 213

Edge Radius-Silicon Blades blade Measure Radius Average Standard Deviation One One 41 Average radius of all silicon 2 54 33.7 3 47 4 56 Standard Deviation of All Silicon 5 48 49.2 5.97 9.77 nm 2 One 19 2 28 3 24 4 22 5 22 23 3.32 3 One 31 2 35 3 35 4 39 5 39 35.8 3.35 4 One 28 2 35 3 39 4 43 5 30 35 6.20 5 One 35 2 32 3 33 4 37 5 28 33 3.39 6 One 28 2 35 3 15 4 22 5 31 26.2 7.85

The base material from which the blades are made is monocrystalline silicon with preferential crystal orientation. However, other orientations of silicon are possible, and other materials capable of isotropic etching are also possible. For example, silicon wafers having <110> and <111> orientations may also be used, and silicon wafers doped with various resistivity and oxygen contents may also be used. In addition, wafers made of other materials such as silicon nitride and gallium arsenide may also be used. The wafer form is one of the forms particularly useful as the base material. In addition to monocrystalline materials, polycrystalline materials may also be used to make surgical blades. Examples of such polycrystalline materials include polycrystalline silicon. As used herein, the term "crystal" is used to refer to both monocrystalline and polycrystalline materials.

Thus, although described with reference to "silicon wafers" throughout this specification, not only the above-described materials combining various directions, but also other suitable materials and their directions can be used by various embodiments of the present invention. It will be apparent to those skilled in the art of the present invention.

1 is a flowchart of a method for manufacturing a double bevel surgical blade from silicon according to a first embodiment of the present invention. The methods of FIGS. 1, 2 and 3 generally illustrate methods of making silicon surgical blades in accordance with the present invention. However, the order of the steps shown in FIGS. 1, 2 and 3 may be varied to manufacture silicon surgical blades with other criteria or under different manufacturing environments.

For example, as shown and described below, FIG. 1 illustrates a method of manufacturing a double oblique blade according to a first embodiment of the present invention, in which one cutting blade is used to produce composite facets. Can be used to make (ie have three or more facets). 31A-31C illustrate such blades and are described in detail below. The method shown and described above may also be used to manufacture a variety of double oblique blades, as shown in FIG. 32 is also described in detail below. Also, as another example of a single blade having two (or more) oblique angles and two (or more) cutting surfaces, a blade having different oblique angles of the blades of the composite blades shown in FIGS. 20B and 20D. Can be prepared by the methods shown and described herein. As such, the methods of FIGS. 1, 2, and 3 represent general embodiments in accordance with the present invention, that is, a silicone surgical blade produced by various alterations or substitutions comprising the same steps is provided herein. Is included in the scope of the technical idea

The method of FIG. 1 illustrates a method of manufacturing a double-sided surgical blade from a crystalline material, such as silicon, preferably in accordance with one embodiment of the present invention, the method of FIG. 1 beginning with step 1002. In step 1002, the silicon wafer is mounted to the mounting assembly 204. As shown in FIG. 4, the silicon wafer 202 is mounted on a wafer frame / ultraviolet (UV) tape assembly (mounting assembly) 204. Mounting assembly 204 is a common method of handling silicon wafer materials in the semiconductor industry. It will be apparent to those skilled in the art that in manufacturing surgical blades according to embodiments of the invention, it is not necessary to mount the silicon (crystal) wafer 202 on the wafer mounting assembly 204. .

FIG. 5 is a side view illustrating the same silicon wafer 202 mounted on the same mounting assembly 204 (although the figures are shown symmetrically to the left or right), but are not necessarily limited thereto. In FIG. 5, the silicon wafer 202 is mounted on the tape 308, and then the tape 308 is mounted to the mounting assembly 204. The silicon wafer 202 includes a first side 304 and a second side 306.

Referring back to FIG. 1, decision step 1004 is followed by step 1002. In decision step 1004, it is determined, if necessary, whether to perform a selective pre-cut of the silicon wafer 202 in step 1006. The preliminary cutting may be performed by the laser water-jet 402 shown in FIG. 6. As shown in FIG. 6, the laser water-jet 402 irradiates the laser beam 404 directly onto the silicon wafer 202 mounted to the mounting assembly 204. As shown in FIG. 6, the silicon wafer 202 is bombarded by the laser beam 404, such that various preliminary cut holes 406 (or through-hole fiducials) are exposed to the silicon wafer ( 202 is formed.

The silicon wafer 202 is removed by the laser beam 404. The ability of the laser beam 404 to remove the silicon wafer 202 is related to the laser wavelength λ. In one embodiment using a silicon wafer, other types of lasers can also be used, but the wavelength that gives the best results in the case of commonly provided YAG lasers is 1064 nm. If other crystals or polycrystalline materials are used, other wavelengths or other types of lasers may be more suitable.

The formed through-hole reference points 406 (multiple holes can be cut in this way) can be used as guides in the machining of the trenches (described in detail in connection with steps 1008 and below), In particular, it can be used when using a dicing saw blade for the machining of trenches. In addition, the through-hole reference points 406 may be cut by the laser beam 402 (eg, excimer laser or laser water-jet) for the same purpose as above. Precut through-hole reference points are typically cut into a plus (″ + ″) shape or circle. However, the choice of through-hole reference point shape is governed by the specific manufacturing tools and environment and, therefore, is not necessarily limited to the two shapes described above.

In addition to using a laser beam to pre-cut through-hole reference points, other mechanical machining methods may also be used, such as drilling tools, mechanical grinding tools and ultrasonic machining tool 100 and the like. Also, the present invention is not necessarily limited thereto. Using the devices with respect to embodiments of the present invention is new, but the devices and methods of use thereof are known to those skilled in the art.

The silicon wafer 202 may be precut prior to machining of the trenches in order to maintain the integration and not separate in the etching step. In order for the dicing blade 502 to machine the trenches around the silicon wafer 202, a laser beam (eg, laser water-jet 402 or excimer laser) scrolls through the elliptical through-hole slots. may be used to scroll (described in detail with reference to FIGS. 7A-7C). Mechanical machining devices and methods (as described above) that are used to create through-hole reference points can also be used to create through-hole slots.

Referring back to FIG. 1, step 1006 (when through-hole reference points 406 are cut into silicon wafer 202), or steps 1002 and 1004 (step 1004, which are silicon wafer mounting steps) are not physical fabrication steps. On the other hand, these decision steps are included to illustrate the entire manufacturing step and its changes). In step 1008, the trenches are machined to the first side 304 of the silicon wafer 202. Several methods can be used for the machining of the trenches, depending on the manufacturing conditions and the desired design of the final silicon surgical blade product.

Methods for machining may use a dicing saw blade, a laser system, an ultrasonic machining tool, a hot-forging process or a router. Other methods can also be used for machining. Each of these methods is described in turn. Both of these methods form the angle (inclined angle) of the surgical blade in the machined trench. As the machining of the trench is performed on the silicon wafer 202, the silicon material may be shaped as a pattern of a dicing saw blade, a pattern formed by an excimer laser, or a pattern formed by an ultrasonic machining tool. Removed to have. In the case of dicing saw blades, the silicone surgical blades only have straight blades. On the other hand, in the latter two methods (excimer laser and ultrasonic machining), the blades can be formed in any desired shape. In the case of a hot forging process, the silicon wafer is heated to be malleable and then compressed between two dies each having a three-dimensional shape of the desired trenches and ″ molding ″ into the heated malleable silicon wafer. The meaning of the above description is that the term "machining" of trenches includes not specified but equivalent methods, as well as the above-mentioned dicing saw blades, excimer lasers, ultrasonic machining or hot forging processes for producing trenches on silicon wafers. All the methods are available. The methods of machining the trenches are described in detail below.

7A-7D illustrate the shapes of a dicing saw blade used for the machining of trenches in a silicon wafer in accordance with an embodiment of the present invention. In FIG. 7A, the first dicing saw blade 502 shows an angle Φ that is the angle formed on the surgical blade after the entire manufacturing process is completed. 7B shows a second dicing saw blade 504, which includes two angled cutting surfaces each representing a cutting angle Φ. FIG. 7C shows a third dicing saw blade 506 having a cutting angle Φ but slightly different in shape from the first dicing saw blade 502. FIG. 7D shows a fourth dicing saw blade 508 that includes two angled cutting surfaces, each representing a cutting angle Φ, similar to FIG. 7B.

Although the dicing saw blades 502, 504, 506, and 508 shown in FIGS. 7A-7D each have the same cutting angle Φ, the cutting angle may be changed for other use of the silicon-based surgical blades. It will be apparent to those skilled in the art that this may vary. Also, as described below, a single silicon surgical blade may have different cutting blades with different angles. The second dicing saw blade 504 can be used to increase the manufacturing capacity for a particular design of the silicon-based surgical blade, or to manufacture silicon surgical blades with two or three cutting blades. Various examples of blade designs are described in detail with reference to FIGS. 20A-20G. In one embodiment of the invention, the dicing saw blade may be a diamond powder saw blade.

A special dicing saw blade is used to machine the channels on the first side 304 of the silicon wafer 202. The configuration of the dicing saw blade is specifically chosen to provide the most desirable surface finish while maintaining an acceptable wear life. The blade of the dicing saw blade includes the shape of the profile, which is the shape of the channel formed in the silicon wafer 202. This shape is related to the blade oblique shape formed. For example, surgical blades typically include comb angles in the range of 15 ° to 45 ° for single bevel blades and half of the bevel angles in the range of 15 ° to 45 ° for double comb blades. Include. The choice of dicing saw blade with regard to etching conditions provides precise control of the oblique angle.

Figure 8 illustrates the operation of a dicing saw blade through a silicon wafer mounted on a back support according to one embodiment of the present invention. FIG. 8 illustrates the operation of a dicing saw blade machine for machining trenches in the first side 304 of the silicon wafer 202. In this example, all of the dicing saw blades 502, 504, 506, or 508 of FIGS. 7A-7D can be used to form silicon-based surgical blade blades. However, note that the blade shapes of FIGS. 7A-7D are not all of the possible shapes that can form dicing saw blades. 9 is a cross-sectional view illustrating a dicing saw blade for machining a trench in a tape-mounted silicon wafer in accordance with one embodiment of the present invention. FIG. 9 shows an enlarged cross-sectional view of the dicing saw blade assembly shown in FIG. 8 actually penetrating the silicon wafer 202. Although the dicing saw blade 502 does not fully penetrate the silicon wafer 202, it can be seen that a single oblique surface penetrates about 50-90% of the thickness of the silicon wafer 202. This applies to all methods for machining (or molding, hot forging) of single slope trenches. When cutting the double oblique surface by dicing saw blades or other machining methods, about 25 to 49% of the thickness of the silicon wafer 202 is machined (or molded) on each side of the silicon wafer 202. do. 10A and 10B illustrate a silicone surgical blade comprising a single oblique cutting blade and a double surgical interfacial blade respectively formed by one embodiment of the present invention.

As discussed above, slots may also be formed in the silicon wafer 202, particularly when using a dicing saw blade to machine the trenches. Slots may be formed in the silicon wafer 202 in a manner similar to the formation of through-hole fiducials, ie using a laser water-jet or excimer laser, but with a very different purpose. Recall that the trench machine uses through-hole reference points to precisely position the silicon wafer 202 on the trench machine. This is particularly effective when forming double oblique blades, since the second machining side (opposite side of the silicon wafer 202) must be accurately positioned in order to identify a properly manufactured double oblique blade. However, slots are used for other purposes. The slots allow the dicing saw blade to cut apart the silicon wafer 202 without cleaving or breaking from the blade (as shown in FIG. 8). This is one embodiment as shown in FIG. 8A. Referring to FIG. 8, machining the trenches as shown without using slots, the machined silicon wafer 202 is apparently easy to break along the machined trenches, which causes the silicon wafer to be trenched. This is because it is very thin in the area and can be broken at small stresses. That is, the machined silicon wafer of FIG. 8 is weak in structural strength. 8 is compared with the silicon wafer of FIG. 8C. The machined silicon wafer 202 of FIG. 8C is harder, thereby increasing manufacturing throughput. Silicon wafers 202 machined by the method shown in FIG. 8C are less destroyed than the silicon wafers of FIG. 8. As shown in Figures 8A and 8B, the slot is made wider than the dicing saw blade and should be long enough so that the dicing saw blade can be inserted into it to start machining at the appropriate depth. Therefore, while the dicing saw blade is downward, the silicon wafer 202 may be broken or broken, and therefore, the silicon wafer 202 should not be cut. That is, cutting starts when the dicing saw blade moves horizontally as designed. 8C shows a series of slots and trenches machined in the first side of the silicon wafer 202.

11 is a block diagram of a laser system used to machine trenches on a silicon wafer in accordance with one embodiment of the present invention. In addition, the trenches may be machined ultrasonically as described with reference to FIG. 12, which is described in detail below. The advantage of these two methods is that blades with nonlinear and compound cutting blade profiles, such as crescent blades, spoon blades, and scleratome blades, can be produced, for example. . 11 shows a simplified laser machine assembly 900. The laser machine assembly 900 consists of a laser 902 that emits a laser beam 904, and a multi-axis control mechanism 906 located on the base 908. Of course, the laser machine assembly 900 may also include a computer and a network interface, but will be omitted for clarity.

When machining trenches using the laser machine assembly 900, the silicon wafer 202 is mounted to a mounting assembly 204, which may be steered by the multi-axis control mechanism 906. The laser machining assembly 900 and various light beam masking techniques can be used to machine the array of blade profiles. The light beam mask is located inside the laser 902 and, through careful design, prevents the laser from removing the undesired silicon material. In the case of double oblique blades, the opposite side is machined in the same way using preliminary cutting chamfers 206A, 206B or reference points 406 for alignment.

In the preparation of wet isotropic etching, the laser 902 is referred to as trench patterns (also referred to as a ″ ablation profile in connection with the use of the laser ”into the first side 304 or the second side 306 of the silicon wafer 202. To be machined accurately and precisely (described in detail with reference to step 1018 of FIG. 1). The use of multi-axis control and internal laser light beam masks is used to raster the ablation profiles described above in the silicon wafer 202. This completes a contoured trench that includes narrow angled slopes that correspond to the demands on surgical blade products. Through this method, various curved profile patterns can be formed. Several types of lasers can be used in the machining step. For example, excimer laser or laser water-jet 402 may be used. The wavelength of the excimer laser 902 may range from 157 nm to 248 nm. Other examples include YAG lasers and lasers having a wavelength of 355 nm. Of course, in the machining of trench patterns, it will be apparent to those skilled in the art that laser beams having wavelengths in the range of 150 nm to 11,000 nm can also be used.

12 is a block diagram of an ultrasonic machining system used to machine trenches on a silicon wafer in accordance with one embodiment of the present invention. Ultrasonic machining is performed using an ultrasonic tool 104 that is precisely machined, and the first side 304 or the second side 306 of the silicon wafer 202 using the abrasive slurry 102. Machine. Machining is carried out on one side at a time. In the case of double oblique blades, the opposite side is machined using the same method as using through-hole reference points 406 for alignment.

Ultrasonic machining is used to accurately and precisely machine trench patterns on the surface of the silicon wafer 202 in the preparation of wet isotropic etching. Ultrasonic machining is performed by vibrating the mandrel / tool 104 ultrasonically. The tool 104 is not in contact with the silicon wafer 202, but is located proximate to the silicon wafer 202 and excites the abrasive slurry 102 by the operation of ultrasonic waves radiated from the tool 104. Ultrasonic waves radiated from the tool 104 exert a force on the abrasive slurry 102, thereby polishing the silicon wafer 202 to correspond to the pattern that is machined onto the tool 104.

The tool 104 is machined through milling, grinding or electrostatic discharge machining (EDM) to form a trench pattern. The pattern formed on the machined silicon wafer 202 corresponds to the pattern machined on the tool 104. Compared with the excimer laser, the ultrasonic machining method has the advantage that numerous ultrasonically machined blade trench patterns can be simultaneously formed on the entire surface of the silicon wafer 202. Thus, the process is fast and relatively inexpensive. In addition, similar to the excimer laser machining method, the ultrasonic machining method can form various curved profile patterns.

13 is a block diagram of a hot forging system used to form trenches on a silicon wafer in accordance with one embodiment of the present invention. Trench shapes may be hot forged into the wafer surface. This method heats the wafer to give malleability. The wafer surfaces are then compressed between two dies having a negative pattern for the trenches formed.

The silicon wafer 202 may be preheated in a heating chamber or completely heated by the heated base 1054 on which the silicon wafer 202 rests. After sufficient time at the heating temperature, the silicon wafer 202 may be malleable. The heated die 1052 then presses the silicon wafer 202 with sufficient pressure to imprint a negative image of the heated die on the first side 304 of the silicon wafer 202. To form a substantially imaginable blade design, the design of the die 1052 includes numerous trenches of various oblique angles, depths, lengths and profiles. Figure 13 is very simplified and exaggerated to clarify the configuration associated with the hot forging process.

26-29 illustrate the use of a router to machine linear or nonlinear trenches in a crystalline material in accordance with one embodiment of the present invention. In FIG. 26, through holes 622 are drilled in the silicon wafer 202. In one embodiment of the invention, through holes 622 are needed to prevent micro cracks. As described above, the through holes 622 may be formed in the silicon wafer 202 using a drill, ultrasonic machining, laser, laser water-jet, or the like. The number of through holes 622 depends on the number of blades formed in the silicon wafer 202. Generally, at least two through holes 622 are required for each blade (to start and end routing), but embodiments of the present invention are not limited to the number of through holes 622.

After all the desired through holes 622 have been drilled into the silicon wafer 202, the router 620 (rotates counterclockwise when viewed from above) descends into the through holes 622 after reaching a predetermined angular velocity. When the router 620 descends to the desired depth, it moves in the desired direction by software control. For this, see FIG. 27. The software control controls the depth at which the router 620 goes down (and goes up after routing), the XY direction in which the router 620 moves within the silicon wafer 202, and the speed at which the router 620 moves in the XY direction. do. The appearance of the router 620 depends on the slope angle required for the desired blade shape. For example, surgical blades used for special purposes require special intrinsic angles and special design blades. 28 illustrates the slopes formed by the router 620 when routing the silicon wafer 202. For example, if a double oblique blade requires an enclosed angle of 30 °, the router angle should be 150 °.

The use of router 620 provides a relatively inexpensive means of forming linear and nonlinear trenches in silicon wafer 202. As shown in FIG. 29, a single blade may have both linear and nonlinear portions. The use of a single, inexpensive tool to form trenches saves time and beauty of the blade manufacturing process, thereby reducing manufacturing and sales costs.

30 shows a flowchart of a method for routing linear or nonlinear trenches in a crystalline material in accordance with one embodiment of the present invention. In step 604, the individual machining process forms the required number of through holes 622 in the silicon wafer 202. In step 606, the router 620 enters the desired through hole 622 to the desired depth after obtaining the desired angular velocity. The software control then moves the router 620 by a defined pattern, thereby forming a trench with the desired bevel angle and design (step 608). If the router encounters the last through hole 622, software control may withdraw the router 620 (step 610). The method is performed repeatedly as necessary to form the optimal number of blades in the silicon wafer 202 (step 612).

Reference is again made to FIG. 1 to illustrate various methods of forming machining trenches. After performing step 1008 of machining the trenches into the first side 304 of the silicon wafer 202, it is determined in decision 2001 whether to coat the silicon wafer 202. FIG. 14 illustrates a silicon wafer coated with a machined side, including a trench machined according to one embodiment of the present invention. Once the coating is determined to be performed, the coating layer 1102 may be formed on the first side 304 of the silicon wafer 202 in step 2002 by one of several techniques known to those skilled in the art. have. Coating layer 1102 facilitates etch control and provides additional strength to the formed blade edges. The silicon wafer 202 is mounted in a deposition chamber, and the entire first side 304 (including flat and trenched areas) of the silicon wafer 202 is coated with a thin film of silicon nitride (Si ₃ N ₄ ). . The thickness of the formed coating layer 1102 may range from 10 nm to 2 μm. The coating layer 1102 may be formed of any material that is harder than the silicon (crystal) wafer 202. In particular, the coating layer 1102 also contains titanium nitride (TiN), aluminum titanium nitride (AlTiN), silicon dioxide (SiO ₂ ), silicon carbide (SiC), titanium carbide (TiC), boron nitride (BN) or diamond-like crystals. Diamond-like-crystals (DLC). Referring to Figures 18A and 18B, the coating of the double comb surgical blades is described in detail below.

If coating layer 1102 is formed in optional step 2002, the next step is dismounting and remounting step 2003 (if no coating is performed, step 1008 also continues to step 2003). In step 2003, the silicon wafer 202 is separated from the tape 308 using the same standard mounting machine. The machine separates the silicon wafer 202 by irradiating ultraviolet (UV) light onto the UV sensitive tape 308 to reduce tack. In addition, a low viscosity tape or heat release tape may be used in place of the UV sensitive tape 308. After sufficient UV exposure, the silicon wafer 202 is easily separated from the tape. The silicon wafer 202 is then remounted with the second side 306 upward to prepare for machining of the trench in the second side 306.

Step 2004 is then performed on the silicon wafer 202. In order to form the double oblique silicon-based surgical blades, the trenches are machined into the second side 306 of the silicon wafer 202 in step 2004 as performed in step 1008. 15 is a cross-sectional view illustrating a dicing saw blade 502 for machining a second trench in a silicon wafer 202 mounted using tape in accordance with one embodiment of the present invention. Of course, excimer laser 902, ultrasonic machine tool 100, or a hot forging process may also be used to machine the second trenches in the silicon wafer 202. In FIG. 15, the dicing saw blade 502 machines the second trench on the second side 306 of the silicon wafer 202. A coating layer 1102 optionally formed in step 2002 is shown. 10A and 10B show the formed single and double oblique cuts, respectively. In FIG. 10A, a single cutting blade with a cutting angle of 0 ° in a single blade assembly is formed on the silicon wafer 202. In FIG. 10B, the second trench is machined on the silicon wafer 202 so as to have the same angle as the first trench (performed by any of the trench machining processes described above). The result is that each cutting blade has a cutting angle Φ, thereby forming a double comb silicon-based surgical blade having a double oblique angle of 2Φ. 16 shows a cross-section of a silicon wafer with trenches machined on both sides in accordance with one embodiment of the present invention.

31A-31C illustrate a double oblique composite facet blade made in accordance with embodiments of the present invention. 31A shows a double oblique composite facet blade 700 in top view. Double oblique composite facet blade 700 is a quad facet blade manufactured according to the methods described herein. Angle θ ₁ shows the implied oblique angle of the first set of faces 704a, 704b, and angle θ ₂ shows the implied oblique angle of the second set of faces 704a, 704b.

The bevels and facets shown in the double oblique composite facet blade 700 may be manufactured using any of the trench forming methods described above. For example, a laser beam 904 can be used when machining the trenches to form the oblique surfaces in the double oblique composite facet blade 700. A laser beam 904 is first passed on the first side of the wafer to machine the first trench, and second pass with appropriate space to machine the second trench. Similarly, the first composite oblique blade 700 may also be formed by a hot forging process described in detail with respect to FIG. 13. Further, as shown in FIGS. 31A-31C, all of the methods described above for machining trenches may be used for machining composite trenches to form a double oblique composite facet blade 700.

32A is a top view of a variable double oblique blade 702. The variable double oblique blade 702 may be manufactured by the method described herein. The angle θ ₄ becomes blunt at the blade tip, resulting in an angle θ ₃ that is sharper towards the shoulder. This design reinforces the sharp tip of the variable double oblique blade 702.

All of the trench forming methods described above can produce the bevel shown in the variable double bevel blade 702. For example, a laser beam 904 may be used to machine the trench to form a bevel on the variable double bevel blade 702. The laser beam 904 can be adjusted to machine the crystalline material by software program control to form various oblique planes. Similarly, the first composite oblique blade 700 can also be formed from the hot forging process described in detail with respect to FIG. 13. Also, as shown in FIGS. 32A-32C, all of the above-described methods for machining trenches may be used to machine complex trenches for forming the variable double oblique blade 702. 32B and 32C show both sides of the variable double oblique blade 702 and show the oblique angles Φ ₃ and Φ ₄ converted to the variable double oblique blade 702 according to the distance from the tip.

20B and 20D are also top views of composite cutting blade blades made to have composite oblique angles. The methods described herein can produce blades, each cutting blade having a different oblique angle, as shown in FIGS. 20B and 20D, for example. 20B and 20D, there are four cutting blades, each of which may have a different single or double oblique angle. In addition, each oblique angle may have one or more facets as described above. These are shown for illustrative purposes only and do not limit the embodiments of the invention described herein.

After step 2004 of processing the trench, the etching of the silicon wafer 202 having the machined double trench is performed in step 1018, or the silicon wafer 202 having the machined double trench is diced in step 1016. Decision on whether or not to perform a step should be made in step 2005. The dicing step 1016 may be performed with a dicing saw blade, a laser beam (eg, an excimer laser, or a laser water-jet 402. Dicing may be substituted for wafer boats (described in detail below). Thereby providing strips that are formed to enable etching in custom fixtures (step 1018).

17A and 17B illustrate an isotropic etching process performed on a silicon wafer having trenches machined on both sides according to one embodiment of the present invention. In etching step 1018, the machined silicon wafer 202 is separated from the tape 308. The silicon wafer 202 is then mounted in a wafer boat and immersed in an isotropic acid bath 1400. In order to maximize the uniformity of the etching treatment step, the temperature, concentration and agitation of the etching solution 1402 are controlled. Isotropic etchant 1402 used includes hydrofluoric acid, nitric acid, and acetic acid (HNA). Other combinations and different concentrations may be used for the same purpose as the above etching. For example, water can replace acetic acid. Instead of immersion etching, spray etching, isotropic xenon diflouride gas etching, and electrolytic etching may also be used to achieve the same results as the above etching. Another example of a composition that may be used for gas etching is sulfa hexafluoride, or other similar fluorine-based gases.

In the etching step, both sides and associated trenches of the silicon wafer 202 are uniformly etched until the opposite trench profiles intersect. The silicon wafer 202 is immediately removed from the etchant 1402 and cleaned every time it is etched. The cutting edge radius obtainable in this process ranges from 5 nm to 500 nm.

Isotropic chemical etching is used to uniformly remove silicon. In the manufacturing process according to one embodiment of the present invention, the wafer surface profile formed by the machining described above is formed uniformly to intersect the profile of the opposite side of the wafer (if single bevel blades are desired, the non-machined facing Silicon wafer surface intersect). In order to obtain the desired sharpness of the blade while maintaining the blade angle, isotropic etching is used. Crossing wafer profiles with machining alone is difficult because the desired blade geometry is too weak to withstand the mechanical and thermal forces of machining. Each of the acidic compositions of the isotropic etchant 1402 has a respective specific function in the isotropic acid bath 1400. First, nitric acid oxidizes the exposed silicon. Second, hydrofluoric acid removes oxidized silicon. Acetic acid acts as a diluent during the etching process. Precise control of composition, temperature and agitation is necessary to obtain reproducible results.

In FIG. 17A, a silicon wafer 202 having no coating layer 1102 is mounted in an isotropic etch bath 1400. Note that each surgical blade, that is, the first surgical blade 1404, the second surgical blade 1406, and the third surgical blade 1408 are connected to each other. As the etchant 1402 acts on the silicon, the molecules are removed one by one over time, so that the surgical blade (second of the first surgical blade 1404) is followed by a second blade 1410, 1412. The width of the silicon (ie, the surgical blade) is reduced until it intersects at the portion that connects to the surgical blade 1406. As a result, several surgical blades 1404, 1406, 1408 are formed. Note that the same angles are maintained in the isotropic etching process except that less silicon material remains because it is dissolved in the etchant 1402.

18A and 18B illustrate an isotropic etching process of a silicon wafer having machined trenches on both sides and a coating layer on only one side, in accordance with another embodiment of the present invention. 18A and 18B, tape 308 and coating layer 1102 remain on silicon wafer 202 to be performed only on second side 306 of silicon wafer 202. However, the wafer need not be mounted on the tape while etching is performed, which is merely optional. In other words, the isotropic etching material 1402 acts only on the exposed silicon wafer 202 and the silicon material (one layer by one) is removed while maintaining the same angle as the angle formed by the machining in step 2004 (since this is 2 is a description of side 306). As a result, in FIG. 18B, the silicon-based surgical blades 1504, 1506, 1508 will have the same angle on the second side 306 as the angle formed by machining in steps 1008 and 2004, and furthermore, the tape ( 308 and optional coating layer 1102 are also present on first side 304 due to presence. This is because it evenly removes layers of silicon molecules along the machined trench surface. The first side 304 of the silicon wafer 202 is not etched at all, providing additional strength to the final silicon-based surgical blade.

Another benefit of applying the optional step 2002 of forming the coating layer 1102 on the first side 304 of the silicon wafer 202 is that the cutting blade (first machined trench side) is stronger than the base silicon material. And a coating layer 1102 (preferably composed of a silicon nitride layer) having properties. Thus, the process of forming the coating layer 1102 makes the cutting blade stronger and more durable. In addition, the coating layer 1102 provides a desirable blade surface wear protection for blades in contact with steel in electromechanically reciprocating blade devices. Table 3 shows the strength characteristics of silicon-based surgical blades containing no coating layer 1102 (silicon) or comprising a coating layer 1102 (silicon nitride).

silicon Silicon nitride Young's Modulus (GPa) 160 323 Yield Strength (GPa) 7 14

Young's modulus (also known as modulus of elasticity) is a property of the inherent rigidity of a material. The higher the Young's modulus, the harder the material. Yield strength is the point at which a material changes from elastic deformation to plastic deformation when a load is applied. In other words, at this point the material is no longer elastic and bends or breaks permanently. After etching (with or without coating layer 1102), the etched silicon wafer 202 is cleaned to remove all of the residual etchant 1402 as a whole.

FIG. 19 illustrates a formed cutting blade of a double comb silicon surgical blade having a coating layer on one side prepared by an embodiment of the present invention. Cutting blades 1602 typically have a radius of 5 to 500 nm, which is similar to the radius of diamond surgical blades but at a much lower manufacturing cost. After performing the etching step of step 1018, the silicon-based surgical blades in step 1020 may be mounted in the same manner as the mounting step 1002 and step 2003.

After mounting step 1020, the silicon-based surgical blades (silicon blades) may be singulated in step 1022, ie, a dicing saw blade, a laser beam (eg, a laser water-jet 402). Or excimer laser), or other suitable means for separating the silicon blades, respectively. As will be apparent to those skilled in the art, lasers with specific wavelengths in the range of 150 nm to 11,000 nm can also be used. Examples of lasers in this wavelength range include excimer lasers. A feature of laser water-jet (YAG lasers) is the ability to scroll curved and broken patterns on the wafer. This provides the manufacturer with the flexibility to manufacture substantially unlimited number of uncut blade blade profiles. The laser water-jet uses the flow of water as a waveguide, allowing the laser to cut similarly to a band saw. This is not possible with the use of current state-of-the-art dicing machines that only dice continuous, straight patterns as described above.

In step 1024, singulated surgical silicon blades are picked up and placed on the blade handling assemblies, according to the consumer's special needs. However, prior to substantial ″ picking and placing (P & P) ″, etched silicon wafers 202 (mounted on tape and frame or tape / wafer frame) may not be suitable for the adhesiveness of tape 308. Ultraviolet (UV) light is irradiated in the wafer mounting machine to reduce. Subsequently, the silicon wafers 202 that are still on the tape that has been ″ decreased ″ or the tape / wafer frame 202 are mounted in a commercially available die attach assembly system. Reviewing the foregoing, the order of the steps may be changed according to various manufacturing environments. Examples of this include a singulation step and a UV light irradiation step. That is, if necessary, the steps may be reversed.

The die attach assembly system removes individual etch silicon surgical blades from the ″ decreased ″ tape and wafer or tape / wafer frame, and places the silicon surgical blades in respective holders within desired tolerances. Attach. Epoxy or adhesive is used to mount the two components. In order to attach the silicone surgical blade to each substrate, other assembly methods may be used, including thermal staking, ultrasonic staking, ultrasonic welding, laser welding, or eutectic bonding. Can be. Finally, in step 1026, the fully assembled silicone surgical blades comprising the handles are packaged for sterilization and protection and shipped for use according to the design of the silicone surgical blade.

Another assembly method that can be used for mounting to the surgical blade holder involves other uses of slots. As mentioned above, the slots can be formed with a laser water-jet or excimer laser and are used to provide openings for the dicing saw blade to contact the silicon wafer 202 when machining the trenches. Another use of the slots may provide a receptacle to the blade for one or more posts in the holder. 24 illustrates such a range. In FIG. 24, the final surgical blade 2402 includes two slots 2404A, 2404B formed in the holder connection area 2406. The slots 2404A, 2404B are connected to the posts 2408A, 2408B of the blade holder 2410. The slots may be formed in the silicon wafer 202 during the manufacturing method, but are preferably formed before the singulation step of the surgical blades is performed. Before the slots 2404A and 2404B and the posts 2408A and 2408B are connected, an adhesive may be applied to an appropriate area to securely attach. The lid 2412 is then glued as shown to provide the final appearance of the final product. By performing a post-slot assembly, additional resistance to pulling forces that may occur in the blades 2402 during the cutting process is provided.

With reference to the description of the manufacturing method of the double oblique silicon-based surgical blade, the manufacturing method of the single oblique surgical blade from silicon for the second embodiment of the present invention shown in FIG. Step 1002, step 1004, step 1006, and step 1008 of FIG. 1 are the same as the method shown in FIG. 2, and thus description thereof will be omitted. However, the manufacturing method of the single oblique surgical blade is different from the manufacturing method of the above-described double oblique surgical blade from the next step, that is, step 1010, and thus will be described.

After step 1008, it is determined whether the silicon wafer 202 machined at decision step 1010 is to be separated from the silicon wafer mounting assembly 204. In the case of separating single trench silicon wafers 202 (step 1012), the dicing step of the single trench wafers performed in step 1016 is also optional. In an optional separation step 1012, the silicon wafer 202 is separated from the tape 308 using the same standard mounting machine.

If the silicon wafer 202 is separated in step 1012, then optionally the silicon wafer 202 may be subjected to a dicing step in step 1016 (ie, the silicon wafer 202 is cut apart to become strips). . Dicing step 1016 may be performed by a dicing blade, excimer laser 902, or laser water-jet 402. Performing the dicing step provides strips formed for etching (step 1018) in custom fixtures on behalf of wafer boats (described in detail below). The next step in the method of making a single comb silicon-based surgical blade following the trench machining step 1008, the separation step 1012, or the dicing step 1016 is step 1018. Step 1018 is an etching step, as described above. Therefore, step 1020, step 1022, step 1024 and step 1026 described above in detail with respect to the manufacture of the double-sided silicon-based surgical blade is performed, a description thereof will be omitted.

3 is a flow chart of a method of manufacturing a single oblique surgical blade from silicon according to a third embodiment of the present invention. In the method shown in FIG. 3, step 1002, step 1004, step 1006, and step 1008 are the same as the method shown in FIG. 2. However, after step 1008 shown in FIG. 3, the coating step 2002 is performed. Coating step 2002 is as described above with reference to Figure 1, and thus description thereof will be omitted. The result of performing the coating step is the same as described above. That is, a coating layer 1102 is formed that covers the machined side of the silicon wafer 202.

After the coating step 2002, in step 2003 the silicon wafer 202 is separated and remounted. This step is also as described above with reference to Fig. 1 (see step 2003 of Fig. 1). The result of performing this step is that the coated side of the silicon wafer 202 faces the mounting assembly 204 downward. Thus, step 1018, step 1020, step 1022, step 1024 and step 1026 are performed, all of which are as described above in detail. As a result of performing this step, a single oblique surgical blade is formed having a first side 304 (machined side) provided to have a coating layer 1102 to increase the strength and durability of the surgical blade. 23A and 23B show and describe a coated single oblique surgical blade in detail.

23A and 23B illustrate an isotropic etching process on a silicon wafer including a trench machined on one side and a coating layer on the opposite side in accordance with another embodiment of the present invention. As shown in FIG. 23A, the silicon wafer 202 includes a coating layer 1102 formed on the first side 304 and mounting in close proximity to the tape 308. The silicon wafer 202 is then immersed in a bath 1400 containing an etchant 1402 as described above in detail. The etchant 1402 begins to etch the second side 306 (″ top ″) of the silicon wafer 202 and removes silicon molecules one by one. Over time, the thickness of the silicon wafer 202 is reduced by the etchant 1402, such that the second side 306 meets the first side 304 and the coating layer 1102. As a result, a single comb silicon-based surgical blade coated with silicon nitride is formed. All the aforementioned advantages of silicon nitride (or coated) blade blades apply equally to blades of this type as shown and described with reference to FIGS. 18A, 18B, and 19.

20A-20G show various examples of silicon-based surgical blades that can be made by the method of the present invention. Various blade designs can be manufactured using the methods described above. Blades comprising single oblique surfaces, symmetrical and asymmetric double oblique surfaces, and curved cutting blades can be produced. In the case of single slopes, machining is performed only on one side of the wafer. A single chisel chisel (see FIG. 20A), three chisel chisels (see FIG. 20B), a slit with two sharp blades (slit, FIG. 20C), a slit with four sharp blades (see FIG. 20D), Such as a stab with one sharp blade (stab, see FIG. 20E), a keratome with one sharp blade (see FIG. 20F) and a crescent with a curved sharp blade (see crescent, see FIG. 20G). Various blade profiles can be formed. The methods described above can be used to vary profile angles, widths, lengths, thicknesses, and oblique angles. The methods described above can be combined with conventional photolithography to produce more various shapes.

Figures 21A and 21B show an enlarged view of 5,000 times each of the silicon surgical blade and the stainless steel surgical blade manufactured by the embodiments of the present invention. Note the difference between FIGS. 21A and 21B. The face shown in FIG. 21A is smoother and more uniform. 22A and 22B show an enlarged view of 10,000 times the top surface of the silicon surgical blade and the stainless steel surgical blade manufactured according to the embodiments of the present invention, respectively. Also note the difference between FIGS. 22A and 22B, wherein the blade formed by the method according to one embodiment of the invention includes a smoother and more uniform surface than the stainless steel surgical blade of FIG. 22B.

25A and 25B illustrate cross-sectional profiles of blade blades formed of crystalline material and blade blades formed of crystalline material comprising a layer conversion process in accordance with one embodiment of the present invention. According to another embodiment of the present invention, after etching the silicon wafer, the surface of the base material may be chemically converted to the new material 2504. This step is also known as thermal oxidation, nitride conversion, or ″ silicon carbide conversion on silicon surface ″. Other components may be formed depending on the elements interacting with the base / blade material. The advantage of changing the surface of the blades to components of the base material is that new materials / surfaces can be selected to form a harder cutting blade. But. Unlike the coating, the cutting blade of the blade maintains its shape and sharpness at the post-etch stage. 25A and 25B, it is noted that even when the conversion process is performed, the depth of the silicon blade does not change. ″ D1 ″ (depth of the silicon-only blade) is equal to ″ D2 ″ (depth of the silicon blade including the conversion layer 2504).

33A-33D show various examples of surgical blades manufactured by the methods of the present invention and that can be used for ophthalmic use. 33A shows a slit blade / knife 720 that can be used for ophthalmic corneal surgery. Slit blade / knife 720 includes a first bevel set 722a and a second bevel set 722b. The first and second oblique sets 722a, 722b may each be a single oblique face having the same or different angles, each may be a double oblique face having the same or different angles, or each oblique set 722a, 722b may each be composite oblique surfaces as well as one or more facets. The combination of the oblique angles, blade angle, thickness and number of facets are all design criteria and may vary depending on the particular use of the slit blade / knife 720 and in accordance with embodiments of the present invention disclosed herein. It can be produced by the methods.

33B shows a microkeratome blade 724 that can be used for ophthalmic refractive surgery (LASIK ^™ ). Microkeratotom blade 724 includes one inclined surface 726, which may be a single or double inclined plane, along with one or more facets. Inclined angles, facets, and combinations of their position and arrangement do not necessarily limit the surgical blades shown in FIGS. 33A-33D and elsewhere herein. Microkeratome blade 724 shows double oblique 726. As described above, the holes 728a and 728b may be used when mounting the microkeratotom blade 724 to the handle.

33C shows a pocket blade / knife 730 that can be used for ophthalmic cataract surgery. Pocket blade / knife 730 shown in FIG. 33C includes single and substantially circular blades. Although the circular shape is preferable, it is not necessarily limited to this. That is, other curved shapes (such as ellipses) may also be used. As mentioned above, the blades may be single, double or composite oblique blades, or a combination thereof. 33D shows a crescent blade / knife 734 that can be used for ophthalmic cataract surgery. The crescent blade / knife 734 shown in FIG. 33D includes single and oval blades. In other words, the oval is preferable, but is not necessarily limited thereto. The crescent blade / knife 734 preferably includes a single oblique angled blade, but the blade may be a single or double oblique blade, with each oblique side comprising one or more faces, as described above.

Referring to FIG. 1, after step 1018, it is determined whether to convert the surface (decision step 1019). If a conversion layer is added (following ″ yes ″ from decision step 1019), the conversion layer is added in step 1021. Then step 1020 follows. If no translation layer is added (following ″ no ″ from decision step 1019), step 1020 follows. The conversion process requires a diffusion or high temperature heat treatment furnace. The base material is heated to a temperature above 500 ° C. in a vacuum or inert gas atmosphere. The selected gases are metered into the heat treatment furnace at a controlled concentration and diffuse into the silicon as a result of the high temperature. Gases diffuse into the silicon and react with the silicon to form new materials. Instead of coating, a new material is formed by diffusion and chemical reaction with the underlying material, thus preserving the original appearance (sharpness) of the silicon blade. An additional advantage of the conversion process is that the optical index of the converted layer is different from the underlying material, so that the blades have color. The color depends on the composition and thickness of the converted material.

The single crystal base material converted at the surface also has better fracture and wear resistance than the unconverted blades. By converting the surface to a hard material, the tendency to form a crack initiation point or break along the crystal plane in the base material is reduced.

Another example of a manufacturing step that can be performed in conjunction with an exchangeable step is a finish matte-finish step. Often, especially when manufacturing surgical blades with embodiments of the present invention, the silicon surface of the blade is very well reflecting light. This may allow surgeons to refuse to use the blade under a microscope with a light source. Thus, the surface of the blade may be provided by a matte treatment that diffuses the incident light (eg, from a high intensity lamp used in a surgical procedure), thereby fainting and fainting. The matte treatment is formed by irradiating the blade surface with a suitable laser to remove areas of the blade surface in accordance with specific patterns and densities. The removed areas have a circular shape, since generally the shape of the incident laser beam is circular, but is not necessarily limited thereto. The dimensions of the areas removed in a circle range from 25 to 50 μm in radius and depend on the manufacturer and type of the JAZER used. The depths of the circularly removed areas range from 10 to 25 μm.

″ Density ″ of the area removed in a circle represents the total ratio of the surface area of the areas removed in the circle. A ″ removed area density ″ of about 5% noticeably blurs the blade from the usual smooth, mirror-like shape. However, the co-location of all of the removed areas does not exhibit a mirror effect of the balance of the blades. Thus, the circularly removed areas should be applied randomly throughout the surface area of the blade. In practice, the graphic file can be formed such that the depressions are located randomly, but the desired effect of the specifically removed region density and randomness can be obtained for the pattern. Such graphic files may be created manually or automatically by a computer program. An additional shape that can be performed is to imprint serial numbers, manufacturer logos, or the name of the surgeon or hospital on the blade.

Typically, a gantry laser or galvo-head laser machine can be used to matte the blade. Gentry lasers are slow but very precise, and Galvohead laser machines are fast, but not as precise as the gentry lasers. The galvohead laser machine is a useful tool because overall precision is not an important factor and manufacturing speed directly affects cost. With thousands of millimeters of motion per second, a typical surgical blade provides about five seconds of etch time in the totally removed area.

Figure 37 shows a comparison of the range of surface roughness of blades made from metal with blades made from silicon by an embodiment of the present invention.

An additional parameter of surgical and non-surgical blades is the surface roughness characteristic. Surface roughness is an important parameter because surface roughness determines the extent to which the skin or material is easy to slide along the blade after the initial cutting performed by the blade edge. Rough surfaces can tear or entangle the skin or material, but smoothing makes it easier to move along the blade. Rough blade surfaces cause tearing or, in worse cases, allow the surgeon to make an abnormal incision (in surgical use). The above scenario is very rare. Blades or mechanical devices made from silicon according to embodiments of the present invention described above have a very smooth surface, that is, surface defects may have a substantially smoother and smoother surface than metal blades. Table 4 is a measurement result of the surface roughness of the metal blade, Table 5 is a measurement result of the surface roughness of the silicon blades according to the embodiments of the present invention described above. Tables 4 and 5 show the surface roughness near the tip of the blade. FIG. 37 shows a first curved portion 372 and a second curved portion 374, where the first curved portion 372 represents a range of surface roughness values Ra of silicon blades manufactured according to the embodiments of the present invention described above. , The second curved portion 374 represents the range of the surface roughness value Ra of the metal blades.

Surface roughness measurement results of metal blades blade Radius One 6020 Average 2 5990 5666 3 4680 4 6800 Standard Deviation 5 4840 890 6 4040

Surface roughness measurement results of silicon blades right left side Average blade Radius Radius Radius Average One 329 461 395 397.5 Å 2 406 492 449 3 449 429 439 Standard deviation 4 316 388 352 57.6 Å 5 336 369 352.5

38 illustrates another method of making silicone surgical blades in accordance with an embodiment of the present invention. The method for manufacturing the silicone surgical blades shown in FIG. 38 produces blades strong enough to be used for similar purposes (ie ophthalmic surgery) in place of the metal blades. The manufacturing method 380 may also include many of the steps described with reference to FIGS. 1 through 3 but will not be described for the sake of brevity. For example, the dicing step 1016 and the addition of the conversion layer (step 1019) may be performed in the manufacturing method 380, a description thereof will be omitted. In addition, to avoid confusion, it may have the same number as the reference number of the component used above in the manufacturing steps if possible. In contrast, when the manufacturing steps are similar but in reality comprise slightly different manufacturing steps than described above, new component reference numbers are used. Further, hereinafter, trench forming step (or dicing step), reference point through hole forming step, or the same equipment as described above in other manufacturing step (e.g. laser water-jet, ultrasonic machine, diamond saw blades, etc.) Same equipment) can be used in the steps described below.

Manufacturing method 380 begins with performing a first laser cut. In FIG. 38, the first laser cutting forms circular reference points 386 (shown in FIG. 39) to align the silicon wafer 202 to the laser and trench dicing equipment. The first laser cutting also cuts slots 390 to form crosshairs 388 and side blades of the blade (see FIG. 42), which are reference points for aligning trenches with respect to the trench dicing equipment. To form.

In step 1008, the oblique sides 392 are trenched by the various methods and equipment described above in detail (see FIG. 40). In step 384, the second laser cut forms horseshoes 394 as shown in FIG. 41. As shown in FIG. 42, the formed trenched wafer 420 is subjected to an etching step 1018. The laser cutting steps can cause mechanical damage to brittle silicon material. The etching step eliminates mechanically caused damage. By eliminating mechanically induced damage, stress concentration points can be eliminated, thereby significantly increasing the yield strength of the material (silicon). Isotropic etchant polishes the surface of the material, in this case both the cut and uncut blades of the blades. The etchant may include hydrofluoric acid, nitric acid and acetic acid. Cracks, chips, scratches, and sharp blades all serve as starting points for cracking brittle materials. When a load or stress is applied to the starting points, catastrophic failure of the mechanical devices is initiated at the starting point. Eliminating or reducing the crack starting points makes the material more durable.

After etching step 1018, the blades are mounted (step 1020), singulated (step 1022), picked and placed (P & P) (step 1024), and also packaged by the consumer's choice (step 1026). ). Since steps 1020 to 1026 are the same as described above in detail, description thereof will be omitted for brevity.

39 to 42 show a silicon wafer processed by the method for manufacturing the silicon surgical blades described in FIG. As described above with reference to Figures 38-42, a silicone surgical blade that may be manufactured by the method of one embodiment of the present invention is shown in Figure 43. Several improvements in the manufacturing method 380 improve the mechanical strength, which will be described in detail below. For example, the horseshoe shown in FIG. 43 is larger in this embodiment compared to the embodiments of the present invention described above. In addition, the first laser cutting described in step 382 of FIG. 38 cuts the slots 390 forming the blades of the blade. In this embodiment, in order to perform etching to increase the blade mechanical strength, the non-cutting blade of the blade is performed to have the maximum length. The first laser cut may also form flanges 396 (shown in FIG. 43). By forming the flange 396 larger, the horseshoe formed in the second laser cutting can be formed more clearly. Also, in the step of forming the trench, each ″ snowflake ″ is cut off. The ″ snowflake ″ pattern is formed in trench forming step 1008 as shown in FIG. 40. The ″ snowflake ″ pattern includes oblique sides 392. Between the ″ snowflakes ″ (oblique sides 392) are not cut. This increases the mechanical strength and integration of the wafer 202. With respect to the laser cutting, it is theoretically possible to change the pulse width and / or pulse repetition frequency (PRF) in order to minimize the mechanical damage of the silicon.

The fabrication method 380 described above with reference to FIGS. 38-43 includes laser ablation, routing, diamond wheel grinding, ultrasonic grinding, lapping, polishing, stamping, embossing. , Ion milling and plasma etching methods (ie, RIE, DRIE, ICP, and ECR) can be used to eliminate the damage caused in various other machining embodiments. In addition, in order to improve the surface quality formed by performing an anisotropic or isotropic wet etching step using KOH, NaOH, CeOH, RbOH, NH ₄ OH, TMAH, EDP or HNA in advance, but not necessarily limited thereto. 380) can be used.

The etching solution (HNA) is an oxidation / reduction etching solution of silicon. Under appropriate conditions, the solution very quickly forms fine electrochemical cells that act as anode / cathode pairs that etch away the silicon substrate and temporarily formed silicon dioxide. This type of reaction works the same on all surfaces. That is, any surface irregularities are substantially curved or eliminated. The formed surfaces become substantially defect free surfaces and have a specular mirror-like appearance and hundreds of millimeters of surface roughness.

Tests were performed on silicon samples by the method described above with respect to FIGS. 38-43. Such silicon samples are referred to as ″ coupons ″. The strength of the silicone coupon was measured as a function of its treatment method. As the test results mean, using the method described above with respect to Figs. 38-43, the modulus of rupture (MOR) measured using the 3-point bending test is very high. Increased. The data disclosed below are based on the strength of the mechanical devices, i.e., by the surgical and non-surgical blades prepared by the method of one embodiment of the invention shown and described with reference to FIGS. It can be used to compare the strength of surgical and non-surgical blades prepared by the other silicone manufacturing methods described herein.

Because of the brittle fracture tendency of single crystal silicon, it was necessary to test coupons that accurately represent silicon products made by the various methods of the present invention described above. Mean MOR and statistical distribution values are required to meaningfully specify the strength of the material.

While performing the strength test, the blade was diced using a diamond wheel, the blade was cut using Gem City's short pulse YAG laser, or the cut was made using Synova's long pulse YAG laser. The blades were evaluated. In addition, the surfaces of the three blades were tested after 50 μm etching or 150 μm etching of silicon. The etchant was used to remove the damage / stress concentration points caused by the cutting method and can also be used to reduce the number of blades that weaken defects.

In each case, 10 coupons with dimensions of 20 mm x 7 mm were measured using the flexural mode in Instron. In each case, etching the sides after cutting significantly increased the mean MOR. The data is summarized in Table 6 below. In Table 6, the initial thickness of the coupon is shown. High MOR values may be caused by an etching that smoothes the chips or scratches on the sides, as shown in FIGS. 44-52. 44 to 52, t _f represents the final thickness of the coupon. By smoothing the chips or scratches on the sides, it substantially reduces the points where catastrophic destruction in the coupon begins. The distribution of the portions etched up to 250 μm (excluding the blades with an etching depth of about 300 to about 250 μm by the gemcity devices) was batched and analyzed for distribution. The data showed a normal distribution with 1254 MPa as mean MOR and 455 MPa as standard deviation.

MOR and material removed by etching as a function of the cutting method <111> direction Span: 16,5 mm to = 300μm MOR (MPa) Gem City laser cut: no etching 164.6 Cut with Gem City laser: etch down to 250μm 693.3 Cutting with synova laser: no etching 336.0 Cut with synova laser: etch down to 250 μm 1205.5 Cutting with Disco Saw: No Etching 507.0 Cutting with Disco Saw: Etch up to 250μm 1240.0 <111> direction to = 400μm Gem City laser cut: no etching 176.1 Cut with Gem City laser: etch down to 250μm 1245.4 Cutting with synova laser: no etching 315.0 Cut with synova laser: etch down to 250 μm 1411.9 Cutting with Disco Saw: No Etching 498.0 Cutting with Disco Saw: Etch up to 250μm 1218.0 The coupon direction is parallel to the flat. Each sample size is 10.

Through the above test, the following conclusions can be drawn.

-The depth of damage caused by gemcity lasers is significantly greater than that of dicing or synova lasers. The intensity (170 MPa) of the portion cut with the gemsci laser is half the intensity (325 MPa) of the portion cut by the synova laser.

The intensity (325 MPa) of the cut portion by the synova laser is about 60% of the intensity (502 MPa) of the cut portion by the Disco dicing saw. This means that the damage depth of the synova laser is deeper.

When 50 μm of material is etched away, the disco-cutting results (1230 MPa) and the synova laser cutting results (1300 MPa) are similar. All of these are more than double the value when dicing and not etching.

53A-53C show results comparing diamond blades, metal blades, and silicon blades manufactured by embodiments of the invention described herein above. Referring to FIG. 53A, silicon blades manufactured by the embodiments of the present invention described herein above have a higher peak stab force in consideration of cost than diamond blades. The silicon blades have a higher peak stab force than metal blades (first thick point 532 of diamond blades, second thick point 534 of silicon blades, and third thick point 536 of metal blades). Compare).

Silicon blades manufactured by the embodiments of the present invention described above may be substantially sharper than metal blades (and may also be sharply roughly at the same level as diamond blades) and substantially more than metal blades. May be smooth (as described above with reference to Tables 4 and 5)

53B and 53C are used to penetrate the pressure and test media required to cause a damage gap of diamond blades, metal blades, and silicon blades manufactured by embodiments of the invention described herein above. Each of the comparison results of the required force is shown.

The steps of method 600 shown in flow chart in FIG. 63 may be associated with other methods described above with reference to FIGS. 1, 2, 3, and 38 for manufacturing surgical or non-surgical blades. Method 600 may form much more complex blades than other embodiments of the present invention described above. The method 600 is described below with respect to the silicon wafer 202. However, as will be apparent to one of ordinary skill in the art, the method 600 and other methods described herein may be of other materials, including but not limited to SiC, sapphire, or aluminum oxide, and the like. The formed wafers 202 may be used. Such materials may be monocrystalline or polycrystalline.

After the through-hole reference points are formed in the silicon wafer (wafer) 202 by steps 1004 according to the methods of FIGS. 1, 2 and 3 and step 382 according to the method of FIG. 38, the manufacturing method 600 is performed. do. The through-hole reference points are used to align the wafer 202 to the various machines used in subsequent steps in the manufacturing method. In step 2000 of the manufacturing method 600, a photoresist layer 540 is formed on the first side of the wafer 202. This is illustrated in FIG. 54. If a double oblique blade is desired, then a photoresist layer 540 is formed on both sides of the wafer 202. This is described in detail below. In step 2002, the photoresist layer 504 is baked, and a patterned photomask 544 is placed on the photoresist covering the wafer 202, followed by a wafer comprising the baked photoresist layer 540 ( 202 and patterned photomask 544 are exposed to ultraviolet light 542 for a period of time. As will be apparent to those skilled in the art, other types of light, such as x-rays, may be used in addition to the ultraviolet light to expose the photoresist layer 540 (depending on the type of photoresist material used). Negative or positive photoresist materials may be used. As will be apparent to those skilled in the art, the patterned photomask 544 can vary depending on the desired oblique angle and type of photoresist material.

As exposed to ultraviolet light 542 and subsequently developed, photoresist layer 540 becomes patterned photoresist layer 541 and pattern of patterned photomask 544 becomes patterned photoresist layer 541. Copied to In the case of positive photoresist materials, portions of the photoresist material exposed to x-rays, ultraviolet light, or other light are removed during development. Negative photoresist material is the opposite. 55A shows a cross section of wafer 202 of FIG. 55 in which a first patterned photomask 544A is located on top of photoresist layer 540 exposed to ultraviolet light 542. 55B is a view of FIG. 55A after the UV exposure is complete and the photoresist layer 540 is developed, and the developed and first patterned photomask 544A is removed to form a patterned photoresist layer 541. The cross section of the wafer 202 is shown. Similar to FIGS. 55A and 55B, FIGS. 56A and 56B show another example of the placement of the second patterned photomask 544B and exposure and development to ultraviolet light. If a double oblique blade is desired, steps 2000 and 2002 can be repeated on the other side of the wafer 202.

After step 2002, manufacturing method 600 performs decision step 2003. As a result of steps 2000 and 2002, a first patterned photoresist layer 541 is included on the first side of the wafer 202. In decision step 2003, it is determined whether the double oblique blade is manufactured. In the case of manufacturing double oblique blades ("yes" path of decision step 2003), it is then determined whether both sides have been processed. If both sides have not been processed (the ″ No ″ path in decision step 2001), then the manufacturing method 600 is repeated steps 2000 and 2002. Laminating a second photoresist layer 540 on a second side of the wafer 202, and in step 2002, bake the second side and a second patterned photomask 544B to a second photoresist layer. 540 is located on. The second photoresist layer 540 is then exposed to ultraviolet light, x-rays, or other types of light through the second patterned photomask 544B. As a result, the second photoresist layer 540 becomes the second patterned photoresist layer 541. The method then returns to step 2003 to re-determine whether one or more double oblique blades are manufactured ("yes" path of decision step 2003). The manufacturing method 600 then determines whether both sides of the wafer 202 have been processed (″ yes ″ path in decision step 2001) and continues to step 2005. In step 2005, a portion of the first and second patterned photoresist layers 540A, 540B is covered with first and second patterned photoresist layers 540A, 540B, respectively, to remove a portion. The wafer 202 having the first and second sides is developed. As discussed above, the portion of the patterned photoresist layers 541A, 541B that is developed and removed depends on whether the photoresist is of a negative or positive type of photoresist material. Manufacturing method 600 then continues to step 2004, which is described in detail below.

In the first run of steps 2000 and 2002, if it is determined not to manufacture the double oblique blades (the ″ no ″ path of decision step 2003, ie single oblique blades), the manufacturing method 600 continues to step 2005. In step 2005, the wafer 202 including only the first side covered with the first patterned photoresist layer 541 is developed to remove a portion of the first patterned photoresist layer 541. As discussed above, the portion of the patterned photoresist layer 541A that is developed and removed depends on whether the photoresist is of a negative or positive type of photoresist material. Manufacturing method 600 then continues to step 2004, which is described in detail below.

The patterned photomask 544 used for the photoresist layer 540 is selected based on the desired oblique angle of the cutting device to be formed. In step 2003, described in detail below, appropriate patterns are selected based on whether the etching method is wet, dry, isotropic or anisotropic. For example, using other etching methods, other patterned photomasks 544 can be used in FIGS. 55A, 55B and 56A, 56B. Many combinations of etchings are possible, and complex masks and repetitive etching can be performed to form almost all oblique angles. Illustratively, but not limited to, using a first patterned photomask 544A, followed by a first etching method, followed by a second patterned photomask 544B, in a first or second etching method. Followed by use.

In step 2004, the wafer 202 is etched. As noted above, etching is the process of removing a layer of crystalline material of the wafer 202 forming a blade (surgery or otherwise) or other type of tool. In this example, etching is used to form trenches that define the shape and angle of the blade. As mentioned above, the trench forming step is generally formed in step 1008 of the methods shown in FIGS. 1, 2, 3 and 38, and by cutting with a diamond saw blade or router, or by laser or Various mechanical methods are used, including, but not necessarily limited to, the use of ultrasonic machining devices. After etching to form the trenches, the patterned photoresist layer 541 is removed and additional etching is performed to complete the material removal step and actually sharpen the blades of the blades. Although the process is more complex, as described above, it is possible to produce very complex blade designs that include complex slopes, composite slopes, and various profile angles.

In step 2004, the wafer 202 is partially etched while being masked with the patterned photoresist layer 541. Once the patterned photoresist layer 541 is developed, the exposed wafer 202 may be etched. Depending on the etchant selected, the etchant may etch the bottom portion of the patterned photoresist layer 541 or reformate the directly patterned photoresist layer 541. This is illustrated in Figures 57A, 57B and 58.

FIG. 57A shows a cross-section of the silicon wafer of FIG. 55B after partial anisotropic etching is performed by one embodiment of the present invention, and FIG. 57B is an isotropic etching process by an anisotropic etching process according to another embodiment of the present invention. The cross-section of the silicon wafer of FIG. 56B after in-situ conversion is shown. FIG. 58 illustrates a cross-section of the silicon wafer of FIG. 56B after performing partial wet isotropic etching in accordance with an embodiment of the present invention.

57A shows an example in which the etchant directly reforms the appearance of the patterned photoresist layer 541. The etchant used in this example is an anisotropic reactive ion etchant. The first etch areas 546A and 546B copy the contour of the patterned photoresist layer 541. In FIG. 58, the wet isotropic etchant etches the bottom of the developed photoresist layer 541. FIG. 58 illustrates the use of the wet isotropic etching method described above in detail with respect to the methods shown in FIGS. 1, 2, 3 and 38. The patterned photoresist layer 541 of FIG. 58 is not affected by the wet isotropic etching method and preserves the original shape (compared to the non-etched wafer 202 of FIG. 56B).

FIG. 57B illustrates a result of combining anisotropic and isotropic reactive ion etching (RIE) methods to form V-groove or second etching areas 548A and 548B. In FIG. 57B, the second etch areas 548A, 548B are formed by a two step RIE method. First, the wafer 202 is etched under plasma conditions, which is consequently anisotropic etch. The result of the wafer is as shown in FIG. 57A. The process parameters are then in-situ transformed so that etching is isotropically performed. The RIE isotropic etchant affects the patterned photoresist layer 541, which can be seen by comparing the wafer 202 of FIG. 57B with the wafer 202 of FIGS. 55B and 57A. With careful selection of the widths of the lines and the spaces between them, the RIE anisotropic portion of the etch can be formed to proceed at different rates into the base material.

FIG. 58 illustrates a cross-section of the silicon wafer of FIG. 56B after wet isotropic etching using a wet isotropic etchant to etch the bottom of the substantially patterned photoresist layer 541. As a result, a narrow V-groove, or third etching area 550 is formed. In any of the etching processes (and various combinations thereof) described above, the etching proceeds only a few tens of micrometers (wafer 202) to form a suitable trench that becomes cutting edge pre-forms on the final blade. Part of the initial thickness)

After step 2004, i.e., after the wafer 202 is etched using the above-described etching methods (or combinations thereof), the patterned photoresist layer 541 may be a suitable wet compound (solvent, commercial photo stripper ( photo stripper, etc.) or removed in step 2006 or ashed in an oxygen plasma apparatus. FIG. 59 shows a cross-section of the wafer of FIG. 57B with the patterned photoresist layer 541 removed. Wafer 202 forms a single oblique blade. FIG. 60 shows a cross-section of wafer 202 of FIG. 58 with patterned photoresist layer 541 removed. Wafer 202 also forms a single oblique blade. FIG. 61 shows a cross-section of a wafer that includes two partial etch sites (two etch sites similar to the etch site in FIG. 59) to form a double oblique blade and with the patterned photoresist layer 541 removed. FIG. 62 shows a cross-section of a wafer that includes two partial etch sites (two etch sites similar to the etch site in FIG. 60) to remove the patterned photoresist layer 541 to form a double oblique blade. do.

Once the patterned photoresist layer 541 is removed in step 2006, the initially etched (or trenched) wafers 202 are mounted on a UV laser dicing tape in step 2008, followed by uncutting of the blades. To form the blades, through-hole slots 390 are cut into wafers 202 in step 2010. These steps are all described in detail. In step 2012, the mounted wafer 202 is removed from the laser tape and cleaned in a series of baths to remove debris, organics and metal impurities. The manufacturing method 600 then returns to the methods described above with respect to FIGS. 1, 2, 3 and 38 to perform the isotropic etching described in step 1018. However, there are a number of additional steps performed to form additional shapes. For example, as described above with respect to step 2002, a coating layer may be formed on one side of the wafer 202 prior to performing the isotropic etching step 1018. Also, as described above with respect to step 1016, an optional dicing step may be performed. After the wet isotropic etching step 1018, if the method of FIG. 1 is performed, step 1019 (optional addition of the conversion layer) is followed, and if the methods of FIGS. 2, 3, and 38 are performed, step 1020 (mounting) ) Is followed.

In etching step 1018, the wafer 202 is wet etched in the isotropic HNA bath described above. The V-grooves (or first, second or third etch areas 546, 548, 550) are very sharp, such as etching away a planar surface to give a final target thickness to the entire wafer / blades. It is formed together by the HNA etching to form cutting blades. Subsequently, the wafer 202 is cleaned as a whole and the etching is stopped. Then, as detailed above, the blades are singulated and engaged with the handles to form useful mechanical cutting tools (medical sharps).

The invention has been described with reference to exemplary embodiments. However, it will be apparent to those skilled in the art that the present invention may be modified in other forms than the above-described exemplary embodiments. This will not depart from the scope of the technical idea of the present invention. The above exemplary embodiments are merely illustrative and are not necessarily limited thereto.

Silicon blades formed by the system and method according to the invention can be manufactured as a manufacturing cost of disposable stainless steel blades, with the sharpness of diamond blades. In addition, the systems and methods according to the present invention can produce surgical and various types of blades having both linear or nonlinear blade oblique surfaces. In addition, the systems and methods according to the present invention can eliminate the mechanical damage caused in silicon crystals by making blades (surgical or non-surgical) or other mechanical devices by the methods described herein. . The blades made in accordance with the present invention can be used in ophthalmic surgical procedures such as cataract and refractive surgery, and can be used for microsurgery, heart, eye, ear, brain, orthopedic and plastic surgery, and for biological use. It can also be used for non-medical and non-biological purposes.

Claims (21)

Forming a trench comprising at least one blade profile of the blade on the first side of the crystalline material in the crystalline material wafer; And Etching at least the first side of the crystalline material to form at least one cutting blade. The method of claim 1, further comprising forming at least one side blade of the blade in the crystalline material. Etching at least the first side of the crystalline material comprises etching at least the one side blade. 3. The method of claim 2, wherein at least one side blade comprises a non-linear portion. 4. The method of claim 3 wherein the non-linear portion is horseshoe shaped. The method of claim 1, wherein the forming of the trench comprises forming first patterns including a first bevel, Etching at least the first side of the crystalline material comprises etching the first inclined surface to form at least a first portion of at least one of the cutting blades. How to prepare. The method of claim 5, wherein the forming of the trench comprises forming second patterns including a second oblique surface. Etching at least the first side of the crystalline material comprises etching the second inclined surface to form at least a second portion of a second cutting blade. How to. The apparatus of claim 6, wherein the first pattern and the second pattern are positioned on the first side of the crystalline material, and the first and second inclined surfaces are spaced apart from each other. How to prepare. 8. The cut from a crystalline material wafer of claim 7, wherein at least one of the first and second patterns comprises a plurality of oblique surfaces formed in a snowflake pattern on the first side of the crystalline material. Method of manufacturing the device. The method of claim 1, further comprising forming at least one slot in the crystalline material that includes at least a non-cutting blade portion of the blade. Method of manufacturing the device. 10. The method of claim 9, wherein forming the at least one slot comprises maximizing the length of the uncut blades of the blade. The method of claim 1, wherein the etching comprises: Mounting a crystalline wafer having at least one blade profile in a wafer boat; Immersing a crystalline wafer having the wafer boat and the at least one blade profile in an isotropic acid bath; And Etching the crystalline material in a uniform manner so that the crystalline material can be removed from the exposed surface in a uniform manner, Sharp cutting device blades are etched into the shape of the at least one blade profile. 12. The method of claim 11 wherein the isotropic acid bath comprises a mixture of hydrofluoric acid, nitric acid, and acetic acid. . 12. The method of claim 11 wherein the isotropic acid bath comprises a mixture of hydrofluoric acid, nitric acid, and water. The method of claim 1, wherein the etching comprises: Mounting a crystalline wafer having at least one blade profile in a wafer boat; Spraying a spray etchant onto the crystalline material wafer having the wafer boat and the at least one blade profile; And Etching the crystalline material in a uniform manner using the spray etchant so that the crystalline material can be removed from the exposed surface in a uniform manner, Sharp cutting device blades are etched into the shape of the at least one blade profile. The method of claim 1, wherein the etching comprises: Mounting a crystalline wafer having at least one blade profile in a wafer boat; Immersing the wafer boat and the crystalline wafer having the at least one blade profile in an isotropic xenon diflouride, sulfa hexafluoride or similar fluorinated gas environment; And Etching the crystalline material in a uniform manner using the isotropic xenon difluoride, sulfahexafluoride or similar fluorine-based gas so that the crystalline material can be removed in a uniform manner from the exposed surface, Sharp cutting device blades are etched into the shape of the at least one blade profile. The method of claim 1, wherein the etching comprises: Mounting a crystalline wafer having at least one blade profile in a wafer boat; Immersing a crystalline material wafer having the wafer boat and the at least one blade profile in an electrolytic bath; And Etching the crystalline material in a uniform manner using the electrolytic bath so that the crystalline material can be removed from the exposed surface in a uniform manner, Sharp cutting device blades are etched into the shape of the at least one blade profile. 3. The apparatus of claim 2, wherein forming at least one side blade comprises transferring energy from the excimer laser or a laser water-jet laser beam to the crystalline material. How to prepare. 10. The cutting device of claim 9, wherein forming at least one slot comprises transferring energy from the excimer laser or a laser water-jet laser beam to the crystalline material. How to manufacture. The method of claim 1, wherein the crystalline material comprises silicon. The method of claim 1, wherein forming the trench comprises: Forming a photoresist layer on the first side of the crystalline material; Patterning the photoresist layer by removing at least a portion of the photoresist layer at least a first portion of the first side of the crystalline material; Partially etching the first portion of the first side of the crystalline material to form the trench; And Removing the photoresist layer at least before the etching of the first side of the crystalline material. The method of claim 1, wherein the partially etching comprises at least one of isotropic reactive ion etching of the first portion of the crystalline material and anisotropic reactive ion etching of the first portion of the crystalline material. A method of manufacturing a cutting device from a crystalline material wafer.

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