JP2000102937A - Method for transferring minute shape and production of binary lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for transferring a minute shape which can mass- produce a product having a minute shape accurately and is excellent in utility and mass productivity and a method for producing a binary lens. SOLUTION: The first mold 1 made of a base material of glass such as quartz in which a minute shape A is formed and a semiconductor forming material such as a germanium or silicon wafer is mounted on a support material so that a minute shape surface A comes to the downside, a room temperature curable resin 4 is cast around the first mold 1, the resin 4 is cured, the second mold 3 of structure in which the first mold 1 is embedded in the resin 4 with the minute shape A exposed on the same level with the surrounding surface is formed, after the second mold 3 being peeled off from the support material, a UV curable resin 5 is set on the surface to which the minute shape of the second mold 3 is exposed, and the resin 5, after being cured, is peeled off from the second mold 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transferring a fine shape for manufacturing a binary lens or the like.

[0002]

2. Description of the Related Art Binary lenses used for optical information communication and hard scanners are made of glass such as quartz and have a length of, for example, 10 mm.
cm, a lens body with a width of about 3 mm (this lens body is a binarized (binary, stepped) Fresnel lens)
Tens of fine lenses having a length of about 0.3 mm and a width of about 0.1 mm are used to read an object by utilizing the diffraction phenomenon of light passing through the lens body. It is.

[0003] By the way, since a binary lens uses a diffracted wave that reinforces with the wavelength of light to be diffracted, high transparency and dimensional accuracy are required. Conventionally, the surface of glass such as quartz is directly processed by photolithography or the like to form a lens shape and cut into a predetermined size.

However, materials that can be processed by photolithography, such as glass such as quartz, are very expensive, and the operation of forming a lens shape requires a very long time, such as mask positioning, exposure, and etching. This is a cumbersome task, and mass production of binary lenses is very difficult.

It is also conceivable to transfer the photo-lithographically processed product as a mold for mass production.
Materials that can be used in photolithography are brittle,
Since the size and shape are also limited, it is very troublesome to use as a mold as it is.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a practical and mass-produced fine shape capable of accurately and mass-producing products having a fine shape such as a binary lens. And a method for manufacturing a binary lens.

[0007]

The gist of the present invention will be described with reference to the accompanying drawings.

A first mold 1 made of a glass base material such as quartz on which a fine shape A is formed, or a semiconductor forming material such as germanium or a silicon wafer is placed on a support member 2 with the fine shape A surface facing down. And the room temperature curable resin 4 that cures at room temperature is poured around the first mold 1 placed on the support member 2, and then the room temperature curable resin 4 is cured to cure the first mold 1. The mold 1 forms a second mold 3 having a structure in which the fine shape A surface is exposed and the fine shape A surface is flush with the surroundings and is embedded in the room temperature curable resin 4. After peeling from the support material 2, the fine shape A of the second mold 3
UV curing resin 5 is provided on the surface where the surface is exposed. Subsequently, after curing the UV curing resin 5, the UV curing resin 5 is separated from the second mold 3. And a method for transferring a fine shape.

In the method of transferring a fine shape according to claim 1, when the UV curable resin 5 is provided on the surface of the second mold 3 where the fine shape surface is exposed, the UV curable resin is further provided. A transparent support member 7 made of a transparent plate or a transparent sheet on 5
Is provided, and then the UV curable resin 5 is cured to form a UV
The present invention relates to a method for transferring a fine shape, wherein the UV curable resin 5 with the transparent support 7 in which the curable resin 5 and the transparent support 7 are integrated is separated from the second mold 3.

The method for transferring a fine shape according to any one of claims 1 and 2, wherein a resin having flexibility after curing is used as the room-temperature-curable resin 4. It is related to.

Further, in the method for transferring a fine shape according to any one of claims 1 and 2, an epoxy resin using a silicone resin, a urethane resin, an amine-based curing agent as the room-temperature-curable resin 4, or these resins. Further, the present invention relates to a method for transferring a fine shape, wherein a resin to which a filler for bringing the coefficient of linear expansion closer to that of the first mold 1 is added is used.

Further, in the method for transferring a fine shape according to any one of claims 1 to 4, the room-temperature-curable resin 4 may contain
The present invention relates to a method for transferring a fine shape, wherein the method is cured at a temperature of up to 60 ° C.

Further, the present invention relates to a method for manufacturing a binary lens, wherein a binary lens is manufactured by the method for transferring a fine shape according to any one of claims 1 to 5.

[0014]

The operation of the mold is facilitated by the cold-setting resin 4 disposed around the first mold 1, so that the fine shape A can be easily transferred to the UV-curable resin 5. Increases efficiency.

[0015] As described above, the present invention provides a practical and mass-producing transfer method of a fine shape and a binary lens which are capable of accurately and mass-producing products having a fine shape such as a binary lens. Production method.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings illustrate one embodiment of the present invention and will be described below.

The present embodiment relates to a method for transferring a fine shape in a method for manufacturing a binary lens.

First, a transfer mold for manufacturing a binary lens is prepared.

A fine shape A that becomes a lens surface of a binary lens after transfer is formed on a substrate made of a semiconductor forming material such as glass such as quartz, germanium, or a silicon wafer by appropriate means such as photolithography and etching. The first mold 1 is formed. In addition, this first type 1
As a material for, a material that does not change its dimensions as much as possible due to a temperature change in each process such as a photolithography process is used.

Subsequently, the first mold 1 is placed on the support 2 so that the fine shape A surface is on the lower side, and a partition plate 6 is provided on the support 2, and the first die 1 is placed between the partition plates 6. For example, a silicone resin 4 is poured onto the first mold 1 as the room temperature curable resin 4 (see FIG. 1). At this time, the silicone resin 4 before curing
Is approximately horizontal due to surface tension.

Subsequently, the silicone resin 4 is cured, and thereafter, the silicone resin 4 is peeled off from the support member 2 so that the fine shape A surface of the first mold 1 is exposed and the fine shape A surface is surrounded by The second mold 3 which is flush with the silicone resin 4) is formed (see FIG. 2). That is, the first mold 1 is embedded in the second mold 3.

The support member 2 has an upper surface (a contact surface with the first mold 1).
Is set to a smoothness of 10 μm or less. It is desirable to use a glass plate 2a for the support material 2 from the viewpoint of cost. However, since the glass plate 2a and the silicone resin 4 are easily adhered to each other due to the self-adhesiveness of the silicone resin 4 and the same silicon compound, It is preferable that the support member 2 is formed by placing a PET sheet or a PC sheet 2b, which is a material that does not adhere to the silicone resin 4, on the glass plate 2a. Also, by setting in this manner, after the silicone resin 4 is cured,
When the second mold 3 is released from the support member 2, the sheet 2b is peeled off and peeled off to facilitate the release operation. still,
Instead of using a smooth jig such as the glass plate 2a, the support member 2 may be composed of only a plastic plate such as a PET sheet or a PC sheet. The plastic plate can be peeled off as it can.)

As the room temperature curable resin 4, a resin which has flexibility after curing and has a property of curing at room temperature is used. The reason for limiting the properties of the cold-setting resin 4 is that the first mold 1 is easily damaged when handling the second mold 3 if the resin does not have flexibility (the first mold 1 is made of a brittle material). Therefore, when manufacturing using the second mold 3, the first mold 1 cannot follow the distortion when a load is applied by a laminating process or the like. The first mold 1 can be prevented from being damaged in order to alleviate the heat.) If the resin is a thermosetting resin, the resin contracts when cooled after being cured, resulting in a difference in the coefficient of thermal expansion. Therefore, the first mold 1 may be damaged. Also,
The shrinkage impairs the planarity of the second mold 3 even if it is not damaged (that is, if the resin is cured at a high temperature (60 ° C. or more) while maintaining the smoothness, the temperature used in the manufacture of the actual binary lens is reduced. (Approximately 40 ° C.), a stress is generated at the interface where the first mold 1 and the support material (room temperature curable resin 4) contact each other due to a difference in thermal expansion coefficient, and the fine shape of the first mold 1 In addition, the parallelism between the surface and the periphery thereof deteriorates, and if the transfer manufacturing is performed while the internal stress remains in the mold (second mold 3), the mold is likely to be damaged in the laminating process, mechanical vibration, etc.). by.

In addition to the silicone resin, the room-temperature-curable resin 4 may be made of a urethane resin or an epoxy resin using an amine-based curing agent, or a filler for the purpose of bringing the linear expansion coefficient of the first mold 1 closer to those resins. May be used.

Further, since the silicone resin used in the present embodiment is rubbery, it generally has a large linear expansion coefficient and easily acts sensitively to a temperature change. In this case, considering the temperature conditions at the time of manufacturing the binary lens, the mold is cured at 20 to 60 ° C., preferably 23 to 50 ° C., which is an environment higher than normal temperature, thereby impairing the parallelism of the mold even in the temperature environment at the time of manufacturing. The second mold 3 can be used without the need. At this time, it is preferable to use an additional type of silicone resin which has as little curing shrinkage as possible when changing from a liquid state to a solid state. Also,
Even if the condensation type is used and the internal stress or the like remains in the silicone resin, the stress is absorbed by the rubber property of the silicone resin, so that the first mold 1 is not damaged.

Next, a binary lens made of a UV (ultraviolet) curable resin is manufactured using the second mold 3 (transfer mold).

The second mold 3 is positioned such that the fine shape A surface of the first mold 1 is on the upper side, and the UV curable resin 5 is laid on the second mold 3 in a laid state. A transparent support plate 7 such as a transparent plate or a transparent sheet made of PET or PC is placed on the UV-curable resin 5, and then an appropriate pressing load such as a roll is applied from above the transparent support plate 7. UV curable resin 5
While adjusting the thickness of the layer, the UV curable resin 5 is spread between the transparent support plate 7 and the second mold 3 (see FIG. 3).
The roll used was a metal roll of 3 kg and a length of 30 cm. Lamination was performed at a constant speed of 0.5 m / min using only the weight of the roll. Is substantially horizontal (there is no step between the surface of the first mold 1 and the surface of the silicone resin portion), so that the resin thickness unevenness after lamination hardly occurs, and after the roll is manually rolled, When the thickness of the cured UV-curable resin 5 was measured, the variation was 5 μm or less.

The transparent support plate 7 used at this time is
After the annealing treatment, a fixed-size cut product in which the temperature and the humidity are controlled must be used. Because the transparent support plate 7
If the temperature, humidity, and internal stress are different, such as when the product is wound into a roll,
This is because a product with high dimensional accuracy may not be obtained.

It is desirable that the transparent support member 7 be made of a transparent material that transmits ultraviolet rays and adheres to the UV-curable resin 5. In this embodiment, a PET with a primer is used.
An annealed product of (polyester) or PC (polycarbonate) or a glass plate with a primer is used.

Subsequently, the UV-curable resin 5 provided on the second mold 3 is irradiated with ultraviolet rays so as to pass through the transparent support member 7 to cure the UV-curable resin 5.

In this ultraviolet irradiation step, the temperature of the transparent support plate 7 is measured before irradiation with ultraviolet rays (a radiation thermometer is preferably used), and a predetermined temperature (temperature ± 5 ° C. during the lens manufacturing step) is obtained. After confirming that the condition (1) is satisfied, ultraviolet irradiation is preferably performed. This is because a product with higher accuracy can be obtained by managing the linear expansion coefficient of the transparent support plate 7 and the accuracy of the dimension of the shape to be transferred. Specifically, the linear expansion coefficient of the first mold 1 that is actually used is 10 ⁻⁶ or less, and the dimension does not significantly affect the temperature. However, when a plastic material other than glass is used, for example, the plastic material is 1
Since the linear expansion coefficient is on the order of 0 ^-5 , the transfer accuracy is greatly affected. However, by controlling the temperature at the time of ultraviolet curing to ± 5 ° C. or less as described above, a transfer accuracy of 0.02% or less can be calculated. Actually, there is a problem of internal stress such as curing shrinkage and curing heat of the UV curable resin 5 and a problem of humidity expansion coefficient.
Temperature control of ± 0.2 to obtain molded products with high dimensional accuracy
It is better to keep the temperature below ° C.

Subsequently, the UV-curable resin 5 with the transparent support 7 in which the cured UV-curable resin 5 and the transparent support 7 are integrated is separated from the second mold 3.

Subsequently, when the cured UV-curable resin 5 with transparent support 7 is die-cut by an appropriate processing means such as cutting, the UV-curable resin 5 with transparent support 7 is die-cut.
Becomes a binary lens.

The main component of the UV-curable resin 5 used in this case is considered to be one with less deterioration of the outer peripheral portion (the silicone resin 4 portion) of the second mold 3 in consideration of lens performance.
Nippon Kayaku Karayad DPCA-120, which is a lactone-modified polyfunctional type, was used. Although the type of the UV-curable resin 5 is appropriately determined for such a reason, other types of U-curable resin 5 may be used, for example, when the silicone resin 4 is used.
Of course, the V-curable resin 5 may be optimal.

In order to speed up the laminating process (the purpose is to improve the wetting of the resin into the mold and to lower the viscosity of the resin), there is a method of increasing the resin temperature of the UV-curable resin 5. However, if the temperature is too high, the UV curable resin 5
Damage to the second mold 3 due to heat, especially the glass transition temperature Tg
When a low-temperature-setting resin 4 (for example, a rubber material such as silicone resin) is disposed around the first mold 1, the low-temperature-setting resin 4 is damaged, and the deterioration speed is increased. I will. In this regard, in the present embodiment, the temperature of the UV curable resin 5 is set at 40 to 50 ° C. to improve the molding cycle without hastening the deterioration of the peripheral portion of the first mold 1.

In the present embodiment, as described above, the UV curable resin 5 generally has a large curing shrinkage during curing, but the holding force of the transparent support member 7 integrated with the UV curable resin 5 is large. As a result, dimensional errors such as shrinkage and elongation become extremely small, and submicron (0.1
Even in the case of the fine shape A requiring transfer accuracy and dimensional accuracy at the level of μm), the curing temperature during UV curing and the linear expansion coefficient (including both the thermal expansion coefficient and the humidity expansion coefficient) of the transparent support plate 7 are taken into consideration. As a result, accurate transfer from the first mold 1 (second mold 3) becomes possible, and a transfer method of a fine shape excellent in practicability, which enables accurate manufacture of a product requiring dimensional accuracy.

Further, since the cold-setting resin 4 has the property of absorbing the stress of the second mold 3, a product having a uniform thickness can be manufactured even if the parallelism of the second mold 3 is impaired. This is a transfer method of a fine shape that is more practical.

The second mold 3 can be used repeatedly, and a method of processing a glass such as quartz or a silicon wafer one by one to form a fine shape one by one as in a conventional method of manufacturing a binary lens. Differently, after the UV curable resin 5 is poured into the second mold 3 and cured, the UV curable resin 5
Since the fine shape A can be formed simply by peeling off the fine shape, a method for transferring a fine shape excellent in practicality and mass productivity in which binary lenses can be easily mass-produced inevitably.

The surface A of the fine shape of the first mold 1 is flush with the periphery of the support 2 by the room temperature curable resin 4 and
Since the room temperature curable resin 4 has a property of absorbing stress, there is no step in the second mold 3. The UV curable resin 5 is provided on the second mold 3, and the transparent support 7 is placed thereon. This makes it possible to perform a uniform laminating step and to produce a highly accurate binary lens or the like.

A room temperature curable resin 4 is provided around the first mold 1.
The practicality that the transfer mold for manufacturing a small binary lens is easy to handle by setting the area of the support material (room temperature curable resin 4) of the peripheral part to be large. This is a method for transferring a fine shape with excellent workability.

If the transfer mold is made of glass or silicon wafer such as quartz, the transfer mold is brittle because the quartz glass or silicon wafer is brittle. Since the second mold 3 has a configuration in which the room temperature curable resin 4 having flexibility after curing, for example, a silicone resin, is disposed around the brittle first mold 1, the room temperature curable resin 4 is provided.
Even if the first mold 1 is distorted due to temperature, humidity, laminating step in the manufacturing process, etc., the first mold 1 is not broken by the room-temperature-curable resin 4 absorbing the stress of distortion. This is a method for transferring a fine shape.

When the room temperature curable resin 4 is a rubber material,
Since the first mold 1 can be more easily taken out than the second mold 3, when the first mold 1 is contaminated with the UV curable resin 5 or the like,
The first mold 1 can be easily cleaned, replaced, and the like, so that it becomes a practically excellent transfer method of a fine shape.

When a binary lens was manufactured according to the present embodiment, a lens having the same accuracy as that of the conventional photolithography method could be obtained. In the manufacturing experiment, the thickness of each member was 0.3 to 0.6 mm for the first mold 1, 4 cm for the silicone resin 1 cm, and 10 cm for the 5 UV curable resin in FIG.
μm, and the transparent support 7 was 250 μm.

In this embodiment, a single first mold 1 is embedded in the silicone resin 4, but if a plurality of first molds 1 are embedded, the mass productivity is increased accordingly.

[Brief description of the drawings]

FIG. 1 is an explanatory side sectional view of this embodiment.

FIG. 2 is an explanatory plan view and an explanatory side sectional view of a second mold 3 of the present embodiment.

FIG. 3 is an explanatory side sectional view of the present embodiment.

[Explanation of symbols]

 A Fine shape 1 First mold 2 Support material 3 Second mold 4 Room temperature curable resin 5 UV curable resin 7 Transparent support material

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H049 AA04 AA14 AA39 AA43 AA45 AA46 4F205 AA31 AA33 AA36 AA39 AA44 AB03 AB11 AC05 AD03 AD04 AD10 AF16 AH74 AR06 GA07 GB01 GC04 GC06 GF01 GF24 GN13 GN24 GN28 GN29

Claims (6)

[Claims] 1. A first mold made of a glass base material such as quartz on which a fine shape is formed, or a semiconductor forming material such as germanium or a silicon wafer is placed on a support material such that the fine shape surface is on the lower side. Placed, around the first mold placed on this support material, poured a room temperature curable resin that cures at room temperature, and then cured the room temperature curable resin, the first mold has a fine shape surface After forming a second mold having a structure in which the exposed state and the micro-shaped surface are flush with the surroundings and embedded in the room temperature curable resin, and after peeling off the second mold from the support material,
A UV-curable resin is provided on the surface where the second mold is exposed, and after the UV-curable resin is cured, the UV-curable resin is peeled off from the second mold. A method for transferring a fine shape. 2. The method of transferring a fine shape according to claim 1, wherein when a UV-curable resin is provided on a surface of the second mold where the fine-shaped surface is exposed, the UV-curable resin is further provided on the UV-curable resin. A transparent support member made of a transparent plate or a transparent sheet is provided, and then the UV-curable resin is cured to form a UV-curable resin with a transparent support material in which the UV-curable resin and the transparent support material are integrated. A method for transferring a fine shape, characterized in that it is separated from a mold. 3. The method for transferring a fine shape according to claim 1, wherein a resin having flexibility after curing is used as the room-temperature-curable resin. 4. The method for transferring a fine shape according to claim 1, wherein the room-temperature-curable resin is a silicone resin, a urethane resin, an epoxy resin using an amine-based curing agent, or an epoxy resin using these resins. A method for transferring a fine shape, characterized by using a resin to which a filler is added so as to approach the linear expansion coefficient of the first type. 5. The method for transferring a fine shape according to claim 1, wherein the room-temperature-curable resin is 20 to 60.
A method for transferring a fine shape, characterized by curing at a temperature of ° C. 6. A method for manufacturing a binary lens, comprising manufacturing a binary lens by the method for transferring a fine shape according to claim 1. Description: