JP4118358B2 - Micro incision device and manufacturing method thereof - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a micro incision device used when processing a fine object such as an egg cell or a protozoan.
[0002]
[Prior art]
Conventionally, a dedicated cutting blade has been used to cut or cut fine objects such as egg cells and protozoa. Such a fine workpiece is generally about several μm to 100 μm in size. Conventionally, a metal blade that has been thinned to several μm by machining or a piece of glass with an appropriate thickness extracted from a broken piece of glass, and placed on a manipulator and moved to cut or cut the workpiece. It was. However, in order to obtain a cutting blade made of such metal or glass fragments, craftsmanship is required, and a stable cutting blade with a high yield cannot be obtained.
[0003]
Therefore, the present applicant has proposed a micro incision device using a semiconductor manufacturing technique in Japanese Patent Application No. 6-218351. FIG. 8 is a schematic perspective view showing the micro incision device 100 proposed by the present applicant in Japanese Patent Application No. Hei 6-218351. This micro cutting device includes a thin film plate 102 serving as a cutting edge and a support 101 that supports the thin film plate, and is obtained by growing and patterning a thin film on a silicon substrate and then etching the silicon substrate. Thus, the micro incision device 100 manufactured using the semiconductor manufacturing technology is installed and operated in a manipulator (not shown).
[0004]
Since this micro incision device is obtained by using a semiconductor manufacturing technique, it has an unprecedented excellent feature that it can be obtained in large quantities at low cost and with good reproducibility.
[0005]
[Problems to be solved by the invention]
Thus, the micro incision device proposed by the present applicant in Japanese Patent Application No. 6-218351 has excellent characteristics as described above. However, in recent years, there has been a desire in the art for a micro incision device with additional properties. A micro incision device is intended for fine workpieces and is generally operated under a microscope. However, even if a microscope is used, if the installation on the manipulator is not appropriate, the support may become an obstacle and come into contact with a preparation or the like on which a workpiece is placed, and improvement in operability is desired. The micro incision device of the present invention has been made in view of such a demand, and an object thereof is to further improve the operability for incising and cutting an object.
[0006]
Alternatively, the micro incision device of the present invention aims to improve durability, particularly mechanical durability.
[0007]
[Means for Solving the Problems]
According to another aspect of the present invention, there is provided a micro-cutting device comprising: a thin film plate formed by patterning a thin film provided on a surface of a silicon substrate having a crystal orientation (100) using a semiconductor manufacturing technique; and the silicon substrate using an etching mask. A support formed by partially etching away, having a shape corresponding to the etching mask, supporting the thin film plate, and having a crystal orientation (111) as a peripheral surface, and reinforcing the thin film plate And a reinforcing member having a crystal orientation different from that of the support, which is made of silicon and is arranged in a beam shape in at least a part of the root region of the thin film plate by under-etching the silicon substrate. And the support includes a main ridge portion on which the thin film plate is fixed and the thin film plate protrudes, and a side ridge located on a side portion of the main ridge portion. It has the door, the reinforcing member, the main the ridge portion provided along the thin plate from a surface of (111), at least a portion of the main ridge is exposed face (111) cage, the thin film plate, said support being arranged to protrude from the extension line of at least one side edge portion or the side edge portion, and, at least the tip portion, characterized that you have to project from the reinforcing member. With this configuration, the support cannot be an obstacle and does not come into contact with the slide glass on which the workpiece is mounted. For this reason, it is possible to provide a micro incision device with improved operability for incising and cutting an object. Furthermore, since the micro incision apparatus according to claim 1 has the reinforcing member, the mechanical durability of the thin film plate is remarkably improved. For this reason, it becomes possible to provide a micro incision device with improved durability. As long as the reinforcing member is provided in a part of the root region, it acts as if it were a beam, and the mechanical durability of the micro incision device is reliably improved. However, the present invention is not limited to this. For example, the reinforcing member may extend to the vicinity of the center of the thin film plate.
[0010]
The micro incision apparatus according to claim 2 is the micro incision apparatus according to claim 1 , wherein a plate reinforcing film for reinforcing the thin film plate is further provided on the surface of the thin film plate on the support side. With this configuration, the mechanical durability of the thin film plate is significantly improved. For this reason, it becomes possible to provide a micro incision device with improved durability. In addition, the mechanical rigidity of the thin film plate is improved, and even a highly rigid object that could not be cut or incised before can be processed.
[0011]
The micro incision device according to claim 3 is the micro incision device according to claim 1 or 2 , wherein an end of the thin film plate has a tapered region. With this configuration, the cutting edge at the end of the thin film plate has an acute angle. For this reason, it becomes possible to provide a micro incision device having a sharp cutting edge.
[0012]
The micro incision device according to claim 4 is the micro incision device according to any one of claims 1 to 3 , wherein an end portion of the thin film plate has a saw blade. With this configuration, it is possible to provide a micro incision device having a saw-shaped cutting edge. When the cutting edge is pressed against a fine workpiece, there is a possibility that the workpiece will escape from the cutting edge so as to slide. However, this can be prevented by making the cutting edge into a saw-tooth shape.
[0013]
A micro incision apparatus according to claim 5 is the micro incision apparatus according to any one of claims 1 to 4 , wherein the thin film plate is a silicon nitride film. Among semiconductor manufacturing technologies, the silicon process for processing a silicon substrate is the most established technology. A silicon nitride film is known as a film that can be easily formed in a silicon process, and serves as a mask material for silicon when silicon is etched with a strong base solution and has a relatively high strength. If silicon processed from a silicon substrate is used for the support and a silicon nitride film is used for the thin film plate, such an excellent silicon process can be used, and it is possible to provide an excellent micro cutting device easily at low cost. Become.
[0015]
According to a sixth aspect of the present invention, in the micro cutting device according to the second aspect, the plate reinforcing film is boron-doped silicon. If the support is formed using a silicon process, a plate reinforcing film made of boron-doped silicon can be easily obtained by doping silicon with boron and etching the silicon. For this reason, it becomes possible to provide a micro incision device with improved mechanical durability and mechanical strength.
According to a seventh aspect of the present invention, there is provided a method for manufacturing a micro-cutting device, comprising preparing a silicon substrate having a crystal orientation of (100) on the upper surface and the lower surface, and forming thin films on the upper surface and the lower surface of the silicon substrate, The thin film on the upper surface is patterned in the shape of a thin film plate, the thin film on the lower surface is patterned in the shape of a support, and the silicon substrate is formed using the upper surface and the thin film on the lower surface as an etching mask. An anisotropic under-etching is performed.
The manufacturing method of the micro cutting device according to claim 8 is the manufacturing method according to claim 7, wherein the anisotropic etching is performed before the periphery of the support is covered with a crystal orientation (111) plane. It is characterized by under-etching by stopping.
According to a ninth aspect of the present invention, there is provided a method for manufacturing a micro incision device according to the seventh or eighth aspect, wherein the anisotropic etching is approximately 10% under-etching.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments will be described with reference to the drawings.
1A and 1B show a micro incision device according to a first embodiment, in which FIG. 1A is a plan view and FIG. 1B is a cross-sectional view taken along a line AA ′ in FIG.
The micro incision device 10 according to the present embodiment includes a support 11 formed from a silicon substrate and a thin film plate 12 formed by patterning a silicon nitride film and supported by the support 11. The support 11 connects the main ridge 15a (line connecting the vertices x and y) that substantially fixes the thin film plate 12 and the side ridge 15b (vertices w and x) located on both sides of the main ridge. Line), 15c (line connecting vertices y and z). A manipulator is connected to the opposite side of the main ridge 15a via a holder (not shown). Reference numeral 14 denotes a silicon nitride film, which is patterned into the shape of the support 11.
[0017]
The thin film plate 12 has a boot-like shape and uses the end portion 13 as a cutting edge. This is formed by a semiconductor manufacturing technique described later. The thin film plate 12 protrudes outside the extension line 16 of one side ridge 15b. In this way, when cutting and incising the workpiece, the side ridges 15b and 15c are not obstructed, and the operability is improved.
[0018]
FIG. 2 is a conceptual diagram of cutting a sea urchin egg 17 (diameter 100 μm) using the micro incision device 10 of the present embodiment. The microtomy device 10 was fixed to the tip of a holder 18 made of an aluminum rod, and the holder 18 was attached to a hydraulic manipulator (not shown). The sea urchin egg 17 to be cut was placed on a slide glass 19, and the manipulator was operated by pressing the cutting blade 13 of the micro incision device from above while observing with a microscope (not shown). The support 11 could easily cut the sea urchin eggs 17 without hitting the slide glass 19, that is, without the support 11 becoming an obstacle to the cutting operation. It has been found that the operability of the micro incision device is greatly improved. Similar cuts were performed on bovine ova (diameter 60 μm) and mouse ovum (diameter 30 μm), and improved operability was also demonstrated in these cuts.
[0019]
Next, the manufacturing process of the micro incision device of this embodiment will be described with reference to FIG. A silicon nitride film (SiNx) 22 having a thickness of 0.7 μm was formed on both sides of a silicon substrate (Si) 21 having a thickness of (100) plane of 250 μm by using low pressure chemical vapor deposition (LPCVD). [FIG. 3 (a)]. Then, the silicon nitride film 22 on the upper surface of the substrate was patterned into the shape of a thin film plate (23), and the silicon nitride film 22 on the lower surface was patterned into the shape of a support (25) [FIG. 3B].
[0020]
For patterning, photolithography and dry etching were used. Dry etching was performed with a reactive ion etching apparatus under the conditions of SF6, He as etching gas, pressure of 0.24 torr, and power of 200 W. Under this condition, the cross-sectional shape of the cutting edge 26 of the thin film plate can be tapered as shown in FIG. 3B, and a sharp cutting edge can be obtained.
[0021]
Then, this board | substrate was immersed in the tetramethylammonium hydroxide (TMAH) aqueous solution, and the board | substrate was etched. When silicon is immersed in an aqueous TMAH solution, anisotropic etching proceeds because the crystal orientation (111) plane has a significantly slower dissolution rate than the (100) plane. Further, the TMAH aqueous solution does not dissolve the silicon nitride film. Therefore, the silicon nitride film 22 functions as an etching mask when the silicon substrate is etched. Etching of the silicon substrate is completed in about 320 minutes at a TMAH temperature of 85 ° C. Here, in order to completely remove an unnecessary area of the substrate, the process was performed for about 30 minutes (about 10%) longer. In this step, the silicon serving as a support remained, and the microincision device was completed [FIG. 3 (c)].
[0022]
As described above, the micro incision apparatus according to the present embodiment can be manufactured by using a semiconductor manufacturing technique, particularly the most established silicon process, so that it is inexpensive and excellent. Further, the shape of the thin film plate can be easily changed by changing a photolithographic mask for patterning a thin film (a silicon nitride film in this embodiment) formed on the substrate. FIG. 4 shows a plan view of a micro incision device 40 according to a modification of the first embodiment. If the thin film plate protrudes from the side ridge or the extension line of the side ridge, the operability is improved.
[0023]
5A is a plan view, and FIG. 5B is a cross-sectional view taken along the line BB ′ of FIG. 5A. However, in the plan view, the reinforcing member 55 is shown through.
The difference from the micro incision device 10 of the first embodiment is that the micro incision device 50 of the second embodiment has a plate reinforcing film 54 formed of boron-doped silicon on the support 51 side of the thin film plate 52. A reinforcing member 55 made of silicon is disposed from the base region of the thin film plate 52 to the center of the thin film plate 52. The reinforcing member 55 is disposed on the surface (the lower surface in the figure). The structure in which the support body 51 formed of silicon supports the thin film plate 52 made of a silicon nitride film is the same as that in the first embodiment.
[0024]
The reinforcing member 55 is arranged like a beam at the root of the thin film plate 52. For this reason, the mechanical durability of the thin film plate 52 is remarkably improved by the reinforcing member 55, and the durability of the micro cutting device 50 is also improved accordingly. As long as the reinforcing member is provided in a part of the root region, the mechanical durability of the micro incision device is surely improved. However, as in the present embodiment, the thin film plate 52 may be extended to the vicinity of the center.
[0025]
The plate reinforcing film 54 is disposed almost entirely under the thin film plate 52. However, if it extends to the vicinity of the cutting edge 53, there is a possibility that the cutting or incision of the object is hindered. For this reason, it is more preferable not to arrange even near the cutting edge 53 as shown in FIG. The plate reinforcing film 54 significantly improves the mechanical durability of the thin film plate 54, and accordingly, the mechanical durability of the micro cutting device is improved. In addition, the mechanical rigidity of the thin film plate is improved, and even a highly rigid object that could not be cut or incised before can be processed.
[0026]
Next, the manufacturing process of the micro incision device of this embodiment will be described with reference to FIG. A thermally oxidized silicon film (not shown) is formed on both sides of a silicon substrate 61 having a (100) plane orientation thickness of 250 μm in accordance with a well-known thermal oxidation method using a silicon process, and a region that later becomes a plate reinforcing film is exposed. Thus, the thermally oxidized silicon film was removed. Boron (B) was doped (diffused) into the silicon substrate 61 in accordance with a well-known thermal diffusion method using the remaining thermally oxidized silicon film as a mask to form boron-doped silicon 62. Boron was diffused by heat treatment at 1175 ° C. for 30 minutes using a solid phase diffusion source. Under this condition, the boron concentration of the boron-doped silicon 62 is 2 * 10 to the 20th power per cubic centimeter at a depth of 2 μm from the surface of the silicon substrate. Next, the thermally oxidized silicon film was removed. The structure obtained through the steps up to here is shown in FIG.
[0027]
Next, a silicon nitride film (SiNx) 63 was formed to a thickness of 0.7 μm using low pressure chemical vapor deposition (LPCVD) [FIG. 6B]. Then, the silicon nitride film 63 on the upper surface of the substrate was patterned into the shape of a thin film plate (64), and the silicon nitride film 63 on the lower surface was patterned into the shape of a support (65) [FIG. 6C].
For patterning, photolithography and dry etching were used. Dry etching was performed with a reactive ion etching apparatus under the conditions of SF6, He as etching gas, pressure of 0.24 torr, and power of 200 W. Under this condition, the cross-sectional shape of the cutting edge 64 of the thin film plate can be tapered as shown in FIG. 6C, and a sharp cutting edge can be obtained.
[0028]
In the patterning of the upper surface of the substrate, the silicon nitride film 63 at the cutting edge was patterned so as to protrude from the boron-doped silicon 62 by about 10 to 20 μm.
Next, in order to form the support 69, the plate reinforcing film 68, and the reinforcing member 66, the substrate was immersed in an aqueous solution of potassium hydroxide (KOH), and the substrate was etched. When silicon is immersed in an aqueous potassium hydroxide (KOH) solution, anisotropic etching proceeds because the crystal orientation (111) plane is significantly slower than the (100) plane in the same manner as the tetramethylammonium hydroxide (TMAH) aqueous solution. . Further, the aqueous potassium hydroxide solution does not dissolve the silicon nitride film. Therefore, the silicon nitride film acts as an etching mask when etching the silicon substrate.
[0029]
In addition, silicon doped with boron has a significantly slower dissolution rate with an aqueous potassium hydroxide solution than silicon not doped with boron. Therefore, the boron-doped silicon 62 remains on the lower surface of the silicon nitride film 63 and becomes the plate reinforcing film 68. Etching of the silicon substrate is just etching in about 100 minutes at a KOH temperature of 85 ° C. However, here, in order to form the reinforcing member 66, under etching was performed for 10 minutes (about 10%) (90 minutes). Under this condition, the reinforcing member 66 was formed like a beam near the base of the thin film plate 64.
[0030]
In this step, the support 69, the plate reinforcing film 68, and the reinforcing member 66 were formed at the same time, and the micro incision device of this embodiment was completed [FIG. 6 (d)].
As described above, the micro incision apparatus according to the present embodiment is not only inexpensive and excellent because it uses a silicon process, but also has a reinforcing member, so that the mechanical durability of the thin film plate is significantly improved. Accordingly, the durability of the micro cutting device is also improved. Further, the plate reinforcing film improves the mechanical durability and mechanical rigidity of the thin film plate, and it is possible to process even a highly rigid object that could not be cut or cut.
[0031]
FIG. 7 is a plan view showing a micro incision device 70 according to a modification of the second embodiment. However, the reinforcing member 75 is shown through. The saw blade 73 of the thin film plate 72 supported by the support 71 is a saw blade. When the cutting edge is pressed against a fine workpiece, there is a possibility that the workpiece will escape from the cutting edge so as to slide. However, this can be prevented by making the cutting edge into a saw-tooth shape. In the micro incision device 70 according to this modification, a plate reinforcing film (not shown) and a reinforcing member 75 are arranged. However, the present invention is not limited to this, and a similar effect can be obtained by arranging a saw blade on the cutting edge of the thin film plate without arranging a plate reinforcing film or a reinforcing member.
[0032]
【The invention's effect】
As described above in detail, the micro incision device of the present invention has an effect that has been recently demanded.
In the micro incision device according to the first aspect, the support does not obstruct the cutting and incision due to the support. For this reason, operability is significantly improved.
[0033]
In the micro incision device according to claim 1 , the reinforcing member has an effect like a beam. For this reason, the mechanical durability of the micro incision device is significantly improved.
Further, if a plate reinforcing film is disposed, the mechanical durability and mechanical rigidity of the thin film plate are remarkably improved.
Further, if the cutting edge is tapered, the cutting characteristics for the workpiece are remarkably improved.
[0034]
Moreover, if the cutting edge is a saw blade, there is an effect of preventing the workpiece from escaping from the cutting edge.
If the silicon process is used, the support, the plate reinforcing film, and the reinforcing member can be formed at the same time, and no particularly complicated process is added.
[Brief description of the drawings]
1A is a plan view of a micro incision device according to a first embodiment, and FIG. 1B is a cross-sectional view taken along a line AA ′ in FIG.
FIG. 2 is a conceptual diagram of cutting sea urchin eggs using the micro incision device according to the first embodiment.
FIG. 3 is a manufacturing process diagram of the micro incision device according to the first embodiment;
FIG. 4 is a plan view showing a micro incision device according to a modification of the first embodiment.
5A is a plan view of a micro incision device according to a second embodiment, and FIG. 5B is a cross-sectional view taken along the line BB ′ of FIG. 5A.
FIG. 6 is a manufacturing process diagram of the microtomy device according to the second embodiment.
FIG. 7 is a plan view showing a micro incision device according to a modification of the second embodiment.
FIG. 8 is a schematic perspective view showing a conventional micro incision device.
[Explanation of symbols]
10, 40, 50, 70, 100 Micro incision device 11, 24, 41, 51, 69, 71, 101 Support 12, 23, 42, 52, 64, 72, 102 Thin film plate 13, 26, 43, 53, 67 Cutting edge 14, 25, 56, 65 Silicon nitride film 15a Main ridge 15b, 15c Side ridge 16 Side ridge 15b extension line 17 Sea urchin egg 18 Holder 19 Slide glass 21, 61 Silicon substrate 22, 63 Silicon nitride film 54, 68 Plate reinforcing film 55, 66, 75 Reinforcing member 62 Boron-doped silicon 73 Saw blade

Claims (9)

A thin film plate formed by patterning a thin film provided on the surface of a silicon substrate having a crystal orientation (100) using a semiconductor manufacturing technique, and the silicon substrate is partially removed by etching using an etching mask. A support having a shape corresponding to the etching mask, supporting the thin film plate, and having a peripheral surface having a crystal orientation (111), and a reinforcing member for the thin film plate; A reinforcing member having a plane of crystal orientation different from that of the support, which is made of silicon and is arranged in a beam shape in at least a part of the base region of the thin film plate by under-etching,
The support has a main ridge portion that fixes the thin film plate and from which the thin film plate protrudes, and a side ridge portion located on a side portion of the main ridge portion,
The reinforcing member is provided along the thin film plate from the (111) surface of the main ridge,
At least a part of the main ridge has a (111) surface exposed,
The thin plate, said support being arranged to protrude from the extension line of at least one side edge portion or the side edge portion, and, microdissection device at least the tip portion, characterized that you have to protrude from the reinforcement member . The micro incision device according to claim 1, wherein the thin film plate is further provided with a plate reinforcing film for reinforcing the thin film plate on a surface on the support side. The micro incision device according to claim 1 or 2, wherein an end portion of the thin film plate has a tapered region. The micro incision device according to any one of claims 1 to 3, wherein an end portion of the thin film plate has a saw blade. The micro incision device according to claim 1, wherein the thin film plate is a silicon nitride film. The micro cutting device according to claim 2, wherein the plate reinforcing film is boron-doped silicon. Preparing a silicon substrate having an upper surface and a lower surface with a (100) crystal orientation;
Forming a thin film on the upper surface and the lower surface of the silicon substrate;
Patterning the thin film on the upper surface into the shape of a thin film plate, patterning the thin film on the lower surface into the shape of a support,
A method for manufacturing a micro incision device, wherein anisotropic under etching is performed on the silicon substrate using the upper surface and the thin film on the lower surface as an etching mask. 8. The micro incision device according to claim 7, wherein the anisotropic etching is performed by under-etching by stopping the etching before the periphery of the support is covered with the crystal orientation (111) plane. Method. 9. The method of manufacturing a micro incision device according to claim 7, wherein the anisotropic etching is approximately 10% under-etching.

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