JP2003048160A - Micro-groove processing method and device - Google Patents

Abstract

[PROBLEMS] To improve efficiency, cost and safety by utilizing the erosion effect of abrasive particles and the chemical action of cerium oxide and quartz glass. SOLUTION: A masking member 5 provided on a surface of a hard member 3 to be processed with a groove having a V-shaped taper 27 corresponding to a position to be processed with a material having a hardness higher than the hardness of the hard member 3. And an aqueous solution containing abrasive particles in a portion corresponding to the groove is jetted with a jet nozzle 1.
Inject from 1. When the aqueous solution fluid is injected into the V-shaped groove, the pressure drop due to friction between the aqueous solution fluid and the groove is reduced, so that the aqueous solution fluid can enter the narrow groove width, so that fine groove processing is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine groove processing method and apparatus for processing a fine structure pattern of high efficiency and high quality in order to manufacture, for example, an optical element or a micropiezoactuator in IT and nanotechnology. .

[0002]

2. Description of the Related Art In recent years, there is an increasing need for fine processing of glass such as optical elements, and many mechanical processing and high energy processing methods such as ductile mode cutting with a single crystal diamond tool and laser processing have been devised. In addition, recently, an example of fine processing by collision of abrasive grains such as jet processing has been reported. In this case, the abrasive grains are carried by air and jetted onto the workpiece. In addition, shape transfer by a mold or processing utilizing a chemical reaction by hydrofluoric acid is performed.

[0003]

In the conventional fine groove machining by jet collision of abrasive grains, there is a problem that the abrasive grains are easily broken when they are jetted perpendicularly to the glass body by air. Further, at this time, since the injection pressure is increased and the air is supplied at high speed, brittle fracture is more likely to occur.

Therefore, such a processing method in which brittle damage is likely to occur is not suitable for manufacturing optical elements and actuators.

On the other hand, there is a problem in that the transfer of the shape by the mold requires cost and time for manufacturing the mold. Further, with respect to processing using a chemical reaction with hydrofluoric acid, there is a problem that processing efficiency is poor and processing of chemicals is difficult because of a long chemical reaction time for fine groove processing by a chemical reaction.

The present invention has been made to solve the above-mentioned problems, and its purpose is to make use of the erosion effect of abrasive particles and the chemical action of cerium oxide and quartz glass, and It is an object of the present invention to provide a fine groove processing method and apparatus capable of improving the efficiency, cost and safety without causing brittle damage to a hard member to be processed.

[0007]

In order to achieve the above-mentioned object, a method for processing fine grooves of the present invention according to claim 1 is to process a surface of a hard member to be processed with a material having a hardness higher than that of the hard member. A masking member having a V-shaped groove corresponding to a position to be covered is coated, and an aqueous solution containing abrasive particles is jetted into the groove to perform fine groove processing on a portion corresponding to the groove. It is a feature.

Therefore, when the aqueous solution containing abrasive particles is jetted toward the V-shaped groove, the V-shaped groove reduces the pressure drop due to the friction between the aqueous solution and the masking member, and the aqueous solution is thin. Since it can enter the groove width, fine grooves can be processed by the erosion effect of the abrasive particles even for grooves having a width smaller than the nozzle diameter. As a result, predetermined fine grooves can be selectively created at predetermined positions on the hard member.

According to a second aspect of the present invention, there is provided a fine groove machining method according to the first aspect, wherein the aqueous solution fluid is jetted in a direction substantially perpendicular to the surface of the hard member. A stagnation point that forms a zero flow velocity region is formed near the surface of the member, and the aqueous solution fluid is bent in the direction along the groove at the stagnation point.

Therefore, a stagnation point is formed in the vicinity of the surface of the hard member immediately below the injection portion where the aqueous solution is supplied in a direction substantially perpendicular to the surface of the hard member, so that brittle damage occurs on the surface of the hard member. There is nothing to do. Further, since the surface of the hard member is deformed and removed by the aqueous solution fluid that bends at the stagnation point and flows in the direction along the groove, the surface of the hard member is deformed and removed with the collision angle of the abrasive particles being substantially zero, so that the fine groove with a good finished surface without brittle damage. Is created.

According to a third aspect of the present invention, there is provided the method of fine groove processing according to the first or second aspect, wherein the abrasive particles are cerium oxide and the hard member is a glass body. To do.

Therefore, since cerium oxide has a large chemical action with the glass body, it can be processed more efficiently by mechanical deformation / removal and chemical action, and a good finished surface can be obtained.

According to a fourth aspect of the present invention, there is provided a fine groove machining apparatus which comprises a masking member having a V-shaped groove corresponding to a position to be machined with a material having a hardness higher than that of a hard member to be machined. A processing table which is installed with the masking member covering the surface of the hard member, and fine groove processing is performed by injecting an aqueous solution containing abrasive particles into the grooves of the masking member to the hard member on the processing table. It is characterized in that it comprises a nozzle and a machining part movement positioning device for relatively moving the nozzle and the machining table in the X-axis and Y-axis directions.

Therefore, when the aqueous solution containing the abrasive particles is jetted toward the V-shaped groove, it is similar to the operation of the first aspect, and the pressure due to the friction between the aqueous solution and the V-shaped groove is exerted. Since the drop is reduced, the aqueous solution fluid can enter the narrow groove width, so that even a groove having a width smaller than the nozzle diameter is subjected to fine groove processing by the erosion effect of the abrasive particles. As a result, predetermined fine grooves can be selectively created at predetermined positions on the hard member.

According to a fifth aspect of the present invention, there is provided a fine groove machining apparatus according to the fourth aspect, wherein the abrasive particles are cerium oxide and the hard member is a glass body. Is.

Therefore, the same effect as the third aspect is provided, and since cerium oxide has a large chemical action with the glass body, it can be processed more efficiently by mechanical deformation / removal and chemical action, and is excellent. A fine finished surface can be obtained.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, erosion processing by a water jet is performed for microgroove manufacturing of, for example, quartz glass as a workpiece to be processed.

Referring to FIG. 2, in a fine processing apparatus 1 for performing fine groove processing according to this embodiment, for example, a mask tool in which the surface of a quartz glass 3 as a hard member as a workpiece is a masking member. It is mounted on the processing table 9 of the processing body 7 in a state of being covered with 5.

Further, the jet nozzle 11 for jetting a water jet toward the above-mentioned workpiece is the processing body 7 described above.
Is fixed to, for example, a tool post 13 as a machining position moving / positioning device, and the position of the jet nozzle 11 is provided such that the position of the jet nozzle 11 can be moved and adjusted in the Z-axis direction according to the machining part of the workpiece. There is. Further, the processing table 9 is provided by NC control so as to be movable and adjustable in the two-dimensional directions of the X axis and the Y axis in a substantially horizontal plane.

The tool post 13 may move in the Z-axis direction and move in the X-axis and Y-axis directions without moving the machining table 9.

The nozzle diameter of the jet nozzle 11 is, for example, 0.25 mm, and the water in the water tank 15 is supplied to the jet nozzle 11 as a water jet through the water supply line 17 in the vicinity of the processing body 7. A pump 19 is provided for this purpose. As the pump 19, a horizontal triple plunger pump having a maximum pressure of 35 MPa and a water absorption of 15.1 l / min is used. The pressure of the water jet is about 1/10 of the injection pressure of the conventional water jet device.

Further, there is provided a slurry supply device 23 for supplying a slurry containing abrasive particles to the jet nozzle 11 via an abrasive supply pipe line 21. The abrasive slurry is a colloidal solution, and in order to be stably mixed at the tip of the jet nozzle 11,
The slurry tank 25 has a double structure so that air and slurry can be sucked simultaneously. Therefore, the abrasive particles are mixed with water at the tip of the jet nozzle 11 and collide with the material at high speed as an aqueous solution fluid containing water as a medium.

In this embodiment, as shown in FIG. 1, the mask tool 5 is for limiting the processing area of the workpiece to a slit having a minute width, and has a thickness of about 5 mm.
It's about. The mask tool 5 is made of a ceramic or cemented carbide that is harder than the hardness of the quartz glass 3 that is the work piece. To prevent pressure drop due to friction between the mask tool 5 and the jet of the aqueous solution fluid, the vicinity of the processed part In this embodiment, however, a taper 27 having a V-shape with an inclination angle of 45 ° is formed. Further, the interval between the left and right tools is adjustable so that the groove width to be machined can be easily changed.

Next, the principle of micro erosion processing (fine groove processing) will be described.

Referring to FIG. 3 (A), in the erosion process by the water jet, a high-speed high-hydraulic aqueous solution containing abrasive ultrafine particles 29 is jetted onto the material surface, and the surface is removed or deformed by the abrasive ultrafine particles 29. To be This processing method is shown in FIG. 5 (A), plastic deformation due to particle collision, as shown in FIG. 5 (B), material removal by crack generation, and shown in FIG. 5 (C). By using the erosion effect that the surface shape changes due to the cutting action by particles like this,
Machining characteristics are governed by particle size, velocity, and collision angle with the work piece.

In general, the glass body is ductilely deformed when the deformation region becomes about 1 μm. Therefore, in this erosion processing method, it is necessary to reduce the particle diameter to about 1 μm or less and process only the surface layer of the glass. is there. Also, FIG.
Since the material removing action due to the crack generation as shown in (B) easily causes brittle damage to the glass body, this state is not preferable for the erosion processing on the glass body, and therefore it is necessary to avoid it.

As the abrasive particles to be collided, in this embodiment, cerium oxide particles having a large chemical action on the processing of the quartz glass 3 are used. This is because when the cerium oxide particles collide with the surface at high speed, the effect is promoted by the local temperature rise in the deformation region. As described above, in the erosion processing method of this embodiment, the groove shape is created by mechanical deformation / removal by cerium oxide particles and chemical action.

Therefore, since the portion of the work piece which has undergone the collision of the abrasive particles is deformed or removed, FIG.
As shown in FIG. 3A, the unprocessed portion is covered with the mask tool 5 and only the processed portion is exposed to the jet flow, and as shown in FIGS. Only processed. Therefore, the shape of the mask tool 5, that is, the mask pattern is changed, and the jet nozzle 1
By moving 1 along the processed groove portion, various groove patterns can be processed.

However, as shown in FIG. 4A, for example, the diameter of the jet nozzle 11 is 0.25.
The width of the groove of the mask tool 5 is 0.02 mm (20μ
In the mask tool 5 such as m), because the pressure drop due to the friction between the tool side surface and the aqueous solution fluid prevents the aqueous solution of the abrasive particles from entering the gap smaller than the diameter of the jet nozzle 11, fine groove machining is performed. Can't do.

Therefore, in this embodiment, as shown in FIG.
As shown in FIG. 5, the V-shaped taper 27 is applied to the end surface of the mask tool 5 to reduce the pressure drop due to the friction between the side surface of the mask tool 5 and the aqueous solution, and to create a processing groove smaller than the nozzle diameter. Is possible. In this processing method, since the abrasive fine particles 29 are used as a tool, there is no deterioration of the shape due to tool wear as in the cutting processing, and the cerium oxide particles that are usually used as an abrasive create and shape the groove shape. Are done at the same time.

In this machining method, in order to create a machined groove having a uniform depth with respect to the workpiece, as described above, the collision angle of the particles with the workpiece is made as small as possible and only the surface layer portion is deformed.・ It must be removed. Further, in the processing of a glass body such as the quartz glass 3 as the workpiece, the brittle damage is more likely to occur as the above-mentioned collision angle increases, so the collision angle needs to be as close to 0 degree as possible.

In this embodiment, FIGS. 1 and 4B are used.
As described above, a high-speed, high-pressure aqueous solution containing abrasive particles is flown in a direction substantially perpendicular to the processed surface. The flow field of this jet flow is controlled by the mask tool 5 having the taper 27 on the end face so as to flow along the V-shaped groove portion, and flows so as to collide and come into contact with the processed surface horizontally.

More specifically, referring to FIGS. 6 and 7, the results of analysis of the jet flow are shown. FIG. 6 shows the water surface of the jet stream and the surrounding air flow, and FIG. 7 shows the velocity field of the jet stream at the center of the groove. In FIG. 7, the distribution of the same velocity is shown, and V ₀ , V ₁ and V ₁ are in order from the slowest velocity of the jet of water and the flow of air.
_{2, V} 3, ..., indicated by _V 8, V _9. Further, the jet direction of water and the flow direction of air are indicated by arrows.

As can be seen from FIG. 7, the jet nozzle 1
A stagnation point (V ₁ , ..., V ₄ is almost applicable) near the machining surface immediately below the machining surface ₁ causes a jet flow flowing in a direction substantially perpendicular to the machining surface. It turns horizontally in the vicinity of the point with respect to the processed surface.

Therefore, the collision angle of the fine particles in the vicinity of the processed surface becomes almost 0 degree, and the processed surface of the quartz glass 3 is shown in FIG.
As shown in (A) or (C), the deformed cutting action by the particles creates a machined groove having a uniform depth and no brittle damage.

Referring to FIG. 8, a product imaged by an AFM (electron force microscope) as a result of the erosion processing as described above is schematically illustrated, and has a width of 20 μm and a depth of 3 μm. An example of fine groove processing is shown. It is understood that the groove shape with a uniform depth and the flattening of the groove surface can be realized by this fine groove processing method.

By the way, referring to FIG. 9, it is illustrated so that the profile of the machined surface can be compared when fine groove machining is performed by changing the jet velocity to 60 m / sec, 120 m / sec, 180 m / sec. ing. At this time, the mask opening width was 20 μm, the jet impingement angle was 90 °, and the abrasive slurry was a colloidal solution of cerium oxide (weight concentration 2.5%, 800 ml) having an average particle diameter of 700 to 1400 nm. The nozzle is reciprocated by feeding along the machining groove.

Therefore, the fine grooves are processed along the edge of the mask tool 5, and the surface roughness of the fine grooves is almost as good as the surface before processing regardless of the difference in jet velocity. The finished surface is obtained. Further, as the jet velocity increases, the V-shaped depth of the groove portion becomes remarkable.

From the above, in the erosion processing by the water jet, the use of the V-shaped mask tool 5 enables the processing of fine grooves finer than the nozzle diameter of the water jet. Further, due to the polishing effect of the cerium oxide particles, a good finished surface without brittle damage can be created on the processed surface of the quartz glass 3.

The present invention is not limited to the above-described embodiment, but can be implemented in other modes by making appropriate changes.

[0041]

As can be understood from the above description of the embodiment of the invention, according to the invention of claim 1, the aqueous solution fluid containing the abrasive particles is jetted toward the V-shaped groove. However, since the pressure drop due to the friction between the aqueous solution and the V-shaped groove is significantly reduced as compared with the conventional case, the aqueous solution can enter the narrow groove width, and therefore even the groove having a width smaller than the nozzle diameter is eroded by the abrasive particles. Fine grooves can be processed by the effect. As a result, it is possible to improve the efficiency, cost and safety in comparison with the conventional processing method without causing brittle damage to the hard member to be processed.

According to the invention of claim 2, the stagnation point can be formed in the vicinity of the surface of the hard member by making the jetting direction of the aqueous solution fluid substantially perpendicular to the surface of the hard member. Micro-groove processing can be performed without causing brittle damage. Moreover, since the aqueous solution fluid bends at the stagnation point and flows in the direction along the groove, the abrasive particles can cut the surface of the hard member with a collision angle of almost zero, so that a fine groove with a good finished surface without brittle damage. Can be created.

According to the third aspect of the invention, since cerium oxide has a large chemical action with the glass body, it can be processed more efficiently by mechanical deformation / removal and chemical action, and a good finished surface can be obtained. Obtainable.

According to the invention of claim 4, which is the same as the effect of claim 1, even when the aqueous solution containing the abrasive particles is jetted toward the V-shaped groove, the aqueous solution and the V-shaped groove are ejected. Since the pressure drop due to friction with the groove of is greatly reduced compared to the conventional one, the aqueous solution can enter the narrow groove width.
Even for a groove having a width smaller than the nozzle diameter, fine groove processing can be performed by the erosion effect of the abrasive particles. As a result, it is possible to improve the efficiency, cost and safety in comparison with the conventional processing method without causing brittle damage to the hard member to be processed.

According to the invention of claim 5, the effect is the same as that of claim 3, and since cerium oxide has a large chemical action with the glass body, it is more efficient by mechanical deformation / removal and chemical action. Can be machined, and a good finished surface can be obtained.

[Brief description of drawings]

1 is a perspective view showing an embodiment of the present invention, in which an aqueous solution is jetted from a jet nozzle onto a glass surface coated with a mask tool having a V-shaped groove.

FIG. 2 is a schematic view of a fine groove processing apparatus used in the embodiment of the present invention.

3A, 3B, and 3C are schematic explanatory views of the principle of fine groove processing.

FIG. 4A is a processing state diagram for a narrow groove width according to the conventional method, and FIG. 4B is a processing state diagram according to the processing method of the present invention.

5A is a state explanatory diagram of an erosion effect due to plastic deformation, FIG. 5B is a state explanatory diagram of material removal due to crack generation, and FIG. 5C is a state explanatory diagram of an erosion effect due to a cutting action.

FIG. 6 is a perspective view showing a flow of an aqueous solution fluid in the vicinity of a processed portion, which is jetted into the groove portion of the mask tool according to the embodiment of the present invention, and the flow of air around the aqueous solution fluid.

FIG. 7 is a perspective view showing a velocity field at the center of the groove of the mask tool.

FIG. 8 is a state diagram of fine groove processing by an electron force microscope.

FIG. 9 shows a profile view and a surface shape view of fine grooves when the jet velocity is changed.

[Explanation of symbols]

1 Fine groove processing equipment 3 Quartz glass (workpiece; hard member) 5 Mask tool (masking member) 7 Processing device body 9 Processing table 11 jet nozzles 13 Tool post (Movement position movement positioning device) 17 Water supply line 21 Abrasive Supply Line 23 Slurry supply device 27 taper 29 Abrasive ultrafine particles

Claims (5)

[Claims] 1. A surface of a hard member to be processed is covered with a masking member having a V-shaped groove corresponding to a position to be processed with a material having a hardness higher than that of the hard member,
A fine groove processing method characterized by ejecting an aqueous solution fluid containing abrasive particles to the groove to perform fine groove processing on a portion corresponding to the groove. 2. A stagnation point which forms a zero flow velocity region near the surface of the hard member is formed by directing the jetting direction of the aqueous solution fluid in a direction substantially perpendicular to the surface of the hard member, and the stagnation of the aqueous solution is performed. The method for processing a fine groove according to claim 1, characterized in that the point is bent in a direction along the groove. 3. The fine groove processing method according to claim 1, wherein the abrasive particles are made of cerium oxide, and the hard member is a glass body. 4. A masking member having a V-shaped groove corresponding to a position to be machined with a material having a hardness higher than that of the hard member to be machined, and the masking member is coated on the surface of the hard member. A processing table to be installed in a state,
A nozzle for performing fine groove processing by injecting an aqueous solution containing abrasive particles into a groove of a masking member with respect to a hard member on the processing table, and the nozzle and the processing table are relatively X-axis and Y-axis. A fine groove machining apparatus, comprising: a machining unit movement positioning device that moves in a direction. 5. The fine groove machining apparatus according to claim 4, wherein the abrasive particles are made of cerium oxide, and the hard member is a glass body.