JP3517640B2 - Die for micro structure array, micro structure array, and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for producing a microstructure array such as a microlens array used in the field of optoelectronics, etc. (In the present specification, a metal mold is used unless otherwise specified. The term "mold" is used to include a mold and a mold master), a microstructure array such as a microlens array, and a method for manufacturing the same.

[0002]

2. Description of the Related Art A microlens array has a plurality of minute, substantially hemispherical lenses each having a diameter of several μm to several 100 μm, and is used in various liquid crystal display devices, light receiving devices, fiber-to-fiber connections in optical communication systems, etc. It has come to be used for purposes.

On the other hand, the development of surface emitting lasers, etc., in which the distance between the light emitting elements can be narrowed and which can be easily arrayed, is progressing, and there is an increasing demand for microlenses having a small lens array spacing and a large numerical aperture (NA).

Similarly, in the light receiving element, with the development of the semiconductor process technology, the element interval is narrowed, and the light receiving element is further miniaturized as seen in CCD and the like. As a result, here again, a microlens array with a narrow lens interval and a large numerical aperture is required. In such a microlens, there is a demand for a microlens having a high light condensing ratio, which has high utilization efficiency of light incident on the lens surface.

Further, there are similar demands in the optical information processing fields expected in the future, such as optical parallel processing / calculation and optical interconnection.

In addition, electroluminescence (EL)
Research and development of self-luminous display devices such as the above have been actively conducted, and proposals for high-definition and high-luminance displays have been made. In such a display, in addition to a microlens array having a small size and a large numerical aperture, there is a demand for a low cost, large area microlens array.

Further, in a microlens array mounted on a liquid crystal projector or the like, in order to eliminate a decrease in the light collection rate due to the displacement between the microlens and the pixel portion and obtain a brighter image, a driving substrate It is necessary to provide an alignment marker that realizes highly accurate alignment with the.

[0008]

[Problems to be Solved by the Invention] Under the above circumstances, the conventional ion exchange method (M. Oikawa, et al., Jpn. J.
Appl. Phys. 20 (1) L51-54, 1981) is used to form a plurality of lenses by increasing the refractive index at a plurality of locations on a substrate made of multi-component glass to form a plurality of lenses. It has been known. However, with this method, the aperture diameter of the lens cannot be made larger than the distance between the lenses, and it is difficult to design a lens having a large numerical aperture.
In addition, a large-scale manufacturing device such as an ion diffusion device is required to manufacture a large-area microlens array, and there is a problem that manufacturing is not easy. In addition, compared to molding using a mold, it is necessary to perform an ion exchange process for each glass, and unless the manufacturing conditions of the manufacturing equipment are carefully controlled, lens quality, for example, variation in focal length is large between lots. There was a problem of becoming. In addition, this method is more expensive than the method using a mold.

Further, in the ion exchange method, alkali ions for ion exchange are indispensable in the glass substrate, the substrate material is limited to alkali glass, and compatibility with semiconductor-based devices which are premised on alkali ion free Is bad. Furthermore, since the coefficient of thermal expansion of the glass substrate itself is greatly different from the coefficient of thermal expansion of the substrate of the light receiving device or the light emitting device,
As the integration density of devices increases, misalignment occurs due to mismatch of thermal expansion coefficients. Originally, it is known that the ion exchange method for the glass surface leaves a compressive strain on the surface, and the problem of the trade-off between the residual stress and the warp deformation of the glass surface is inevitably caused, and the microlens array becomes large-sized. As a result, it becomes difficult to bond and join the substrate of the light receiving device or the light emitting device.

Another method is the registry flow method (D. Daly, et al., Proc. MicrolensArrays Teddingto
n., p23-34, 1991). In this method, a resin formed on a substrate is patterned into a cylindrical shape using a photolithography process, heated and reflowed to manufacture a microlens array. By this method, lenses of various shapes can be manufactured at low cost. In addition, there are no problems such as thermal expansion coefficient and warpage as compared with the ion exchange method. However, in this method, the shape of the microlens strongly depends on the thickness of the resin, the wettability between the substrate and the resin, and the heating temperature. Variations are likely to occur.

Another method is to prepare an original plate of a microlens array, apply a lens material to the original plate, and peel off the applied lens material. In the production of a mold as an original plate, a method of drawing with an electron beam (JP-A-1-261601) and a method of etching a part of a metal plate (JP-A-5-30309)
Issue gazette). According to these methods, the microlens can be duplicated by molding, variation from lot to lot does not easily occur, and it can be produced at low cost. Further, as compared with the ion exchange method, it is possible to avoid problems such as occurrence of alignment error and warpage due to the difference in thermal expansion coefficient. However, in the method using the electron beam, the electron beam drawing apparatus is expensive, a large amount of capital investment is required, and the drawing area is limited.
There is a problem that it is difficult to produce an original plate having a large area of a corner or more.

As another method, a mask layer having a one-dimensionally or two-dimensionally arranged opening pattern is formed on a base material, and etching is performed from the opening (Japanese Patent Laid-Open No. Hei.
8-136704). However, in this method, since etching is performed from the resist opening,
The bottom of the dug portion is flattened, and it is difficult to collect light below the diameter of the opening. In addition, since the method of etching mainly uses isotropic etching utilizing a chemical reaction, there is a problem that the composition cannot be etched into a desired shape even if the composition or crystal structure of the base material is slightly changed.

As a method for solving the above-mentioned problems, a hemispherical structure array is prepared by electroplating, a mold for a microlens is prepared using this as an original plate, and a microlens array is prepared from this mold. Has been devised (Japanese Patent Publication No. 64-10169). According to this method, it is possible to manufacture a microlens mold that is easy to make large, the manufacturing process is easy, the controllability is high, and the cost is low. Further, it becomes possible to manufacture a microlens having a small radius of curvature by the method using electroplating.

As a method of forming an alignment marker, there has been proposed a method of forming a pattern for a lens and a pattern for an alignment marker in the same process when forming a resist pattern (Japanese Patent Laid-Open No. 09-189901).

However, in this method, the Japanese Patent Publication No. 64-1016 is used.
Applying the method of Japanese Patent Publication No. 9 and forming a pattern for a lens and a pattern for an alignment marker in the same process at the time of forming a resist pattern, and then performing electroplating, a distribution of current density is generated due to the pattern shape for the alignment marker However, the electric field is concentrated in the peripheral portion of the lens array pattern to promote the plating growth, resulting in an in-plane distribution in the size of the hemisphere. Further, a current density distribution is generated around the alignment marker pattern, which causes a distribution in the size of the plating layer grown in a desired microlens array region.

The present invention has been made in view of the above problems of the prior art, and its objects are (1) easy fabrication process and high controllability, and (2) in-plane microstructure array. The distribution can be reduced, (3) the radius of curvature of the microstructure can be reduced, (4) it can be applied to a cross-shaped alignment marker, and (5) an alignment marker for realizing highly accurate alignment can be provided. It is to provide a mold for a microstructure array such as a microlens array, a microstructure array such as a microlens array, and a manufacturing method thereof.

[0017]

Means and Actions for Solving the Problems A method of manufacturing a microstructure array such as a mold for a microlens array of the present invention which achieves the above object uses a substrate having a conductive portion, and A step of forming an insulative first mask layer on the characteristic portion, and (2) forming a plurality of microstructure openings in the first mask layer at intervals corresponding to a desired microstructure array array. A step of forming an alignment marker opening in the same process, (3) a first on the opening and the first mask layer through the opening by electroplating or electrodeposition using the conductive portion as a cathode
And a step of forming a plating layer or an electrodeposition layer, wherein the alignment marker opening in step (2) is formed from a recent microstructure opening The maximum pitch (if the openings are arranged at equal intervals, that pitch, and if the intervals change, it is the maximum pitch)
The ratio of the area of the alignment marker opening to the area of the region surrounded by the microstructure opening existing around the alignment marker opening is 1/2 or more. Characterized by being small. If these conditions are satisfied, the current density distribution tends to be suppressed during plating or electrodeposition, and the in-plane distribution of the size (height, diameter, width, etc.) of the plating layer or electrodeposition layer is suppressed, Overall, the desired microstructure array and alignment marker will be formed.

Based on the above basic configuration,
More specific embodiments are possible. Further, (4) the first
The step of removing the mask layer may be performed. If possible, the structure obtained in the step (3) may be used as it is (this is possible when the first mask layer is PSG or the like having good adhesion to the conductive portion. ,
The plurality of first plating layers or electrodeposition layers may be separated or may be formed until they are continuous), or a structure obtained by removing the first mask layer may be used.

Further, (5) a step of forming a second mask layer on a desired microstructure array region and an alignment marker region of the substrate and the first plating layer or electrodeposition layer, (6) the above The step of removing the first plating layer or the electrodeposition layer in the area where the second mask layer is not formed by etching, and the step of (7) removing the second mask layer may be performed. Thereby, the in-plane distribution of the obtained microstructure array can be made smaller. If possible, the structure obtained in the step (7) may be used as it is.

Further, after the step (3), (4) or (7), (8) the second plating layer or the second plating layer is formed from the first plating layer or the electrodeposition layer to the conductive portion or the first mask layer. The process of forming an electrodeposition layer may be performed. As a result, the in-plane distribution of the microstructure array can be further reduced, and the first plating layer or electrodeposition layer can be firmly fixed to the conductive portion or the first mask layer to further strengthen the structure.

In the step (2), the diameter or width (short side) of the alignment marker opening is equal to or smaller than the diameter or width of the circular or slit-shaped microstructure opening. It is more suitable. A circular or slit-like opening for a microstructure can form a substantially hemispherical or semicylindrical microstructure array (which can be a hemispherical microlens array or a mold for a lenticular lens). In the step (2), the alignment marker openings include those having a square shape, those having a rectangular shape, those having a polygonal shape, and those having a ring shape. This may be determined according to the application.

In the step (6), the first plating layer can be removed by electrolytic etching or the like. In addition, in the step (8), the second plating layer may be formed by electroless plating or the like.

The above-mentioned microstructure array is typically manufactured as a mold for a microstructure array or a mold for a microlens array.

Furthermore, a microstructure array such as a mold for a microlens array of the present invention that achieves the above object is a microstructure array manufactured by the above-described method for manufacturing a microstructure array, A first plating layer or electrodeposition layer outside the microstructure group of the body array,
Or a structure for an alignment marker comprising a first plating layer or electrodeposition layer and a first plating layer or electrodeposition layer and a second plating layer or electrodeposition layer formed on a conductive part or a first mask layer In (1), there is no flat portion between the closest points of the adjacent first plating layer or electrodeposition layer or the second plating layer or electrodeposition layer. As a result, a microstructure array such as a die for a microlens array with a small cross-sectional distribution of the size of the microstructure array is provided, with a cross-shaped structure for the alignment marker that enables highly accurate alignment. it can.

The structure for the alignment marker includes a rod-shaped first plating layer or electrodeposition layer or a single body or an assembly of the first and second plating layers or electrodeposition layers, or a ring-shaped first layer. Or a single body of the first and second plating layers or electrodeposition layers or an aggregate thereof.

In this structure, the first hemispherical structure is formed on the microstructure (for example, a conductive substrate or a substrate having an electrode layer and has a cylindrical axis corresponding to the lens group of the microlens array). A microstructure including a plating layer, a first plating layer, and a second plating layer formed on the electrode layer) and the alignment marker structure (for example, the first plating outside the lens group of the microlens array) The height of the layer and the alignment marker structure comprising the first plating layer and the second plating layer formed on the electrode layer can be easily made substantially equal, and the distribution of the height can be easily 5%. Can be done within.

All or part of the cross-sectional shape of the alignment marker structure formed by plating or electrodeposition may be curved or semicircular.

Of course, the microstructure array is typically a microstructure array mold or a microlens array mold.

Further, an image pickup device or a display device of the present invention that achieves the above object is a microstructure array configured as the microlens array of the present invention, or a microfabricated by a mold for a microlens array of the present invention. It is characterized in that the lens array is mounted in a state where each microlens is aligned with each light receiving portion or each pixel portion using the alignment marker.

The above are the basic and more specific components of the present invention, and the details and operation thereof will be further described below along with typical examples.

First, the principle of forming a hemispherical microstructure will be described. Electroplating or electrodeposition (in the following description, plating is used) is performed on a minute or minute opening of an insulating layer formed on a conductive substrate or a substrate having an electrode layer (substrate having a conductive portion). Then, first, a plating layer is deposited in the opening, and when electroplating is further performed, the first plating layer starts to grow on the opening and the mask layer. When the size (diameter or width) of the opening is sufficiently smaller than that of the anode for electroplating, the first plating layer grows isotropically with respect to the center of the diameter or width, and the first plating layer having a hemispherical shape is formed. A plating layer is formed on the opening and the mask layer. By making the shape of the opening circular, the first plating layer can grow isotropically with respect to the center of the diameter on the mask layer. Compared with the method of forming an original plate by etching, if the current flowing between the anode and the cathode is stopped when the desired shape is obtained, the deposition of the plating can be stopped. Unnecessary shape error can be avoided and the controllability of fabrication is good.

Next, a typical example of a method for producing a mold for a microstructure array, which is typically a microlens array, will be shown. Here, when a microlens or a microlens array is referred to, it means a microstructure as a representative. As a matter of course, what is described here can be applied to a method for manufacturing a mold for another microstructure array. First, a first mask layer is formed over a conductive substrate or a substrate having an electrode layer. The plating substrate material may be any of metal, semiconductor, and insulator materials, and a metal plate having a good flatness, a glass substrate, a silicon wafer, or the like can be used. If a metal material is used as the plating substrate, it is not necessary to form the electrode layer. Further, when a semiconductor is used, it is not always necessary to form an electrode layer as long as it has a conductivity that allows electroplating. The electrode layer is selected from materials that are not corroded by the plating solution used because they are exposed to the plating solution. However, since a part of the first plating layer formed on this electrode layer is removed by etching in a later step, a material which does not form an alloy layer with the first plating layer is preferable. Further, the electrode layer is preferably made of a material that is not etched in the plating solution. Any material having an insulating property may be used for the first mask layer, and either an inorganic insulator or an organic insulator can be used. As a method of forming the electrode layer and the first mask layer, a vacuum deposition method, a spin coating method, a dipping method, a chemical deposition method (CV) is used.
A thin film forming method such as D) is used.

Next, a plurality of microlens openings are formed in the first mask layer at a pitch corresponding to the pitch of the microlens array in a region wider than a predetermined microlens array group region (that is, use region). To do. The shape of the opening is preferably circular or the like. In forming the opening, the opening is formed by a semiconductor photolithography process capable of forming a minute or fine opening and etching. When a photoresist is used as the first mask layer, the etching process can be omitted (that is, exposure and development are sufficient).

At this time, the opening for the alignment marker is also formed in the same process at the position corresponding to the alignment marker. This makes it possible to form an alignment marker for realizing highly accurate alignment. The opening at the position corresponding to the alignment marker may be circular, square, rectangular, ring-shaped, or any other shape. Here, an alignment marker corresponding to a cross-shaped marker can also be formed by disposing the opening. In addition, by forming the opening in a ring shape, it is possible to form an alignment marker that is compatible with a large circular alignment marker on the side of the bonded substrate such as a drive substrate, which improves alignment accuracy. To be The diameter or width (short side) of the opening that serves as the alignment marker is preferably equal to or smaller than the diameter of the circular opening corresponding to the microlens array. This is to soften the current density distribution.

The alignment marker opening is separated from the closest microlens opening by at least one pitch of the opening pitch and is surrounded by the microlens openings existing around the alignment marker opening. The ratio of the area of the alignment marker opening to the area of the formed region is preferably smaller than 1/2. If the distance from the microlens opening is smaller than one pitch of the microlens opening, the alignment marker opening is affected by the current density distribution and is used for the first plating layer or the alignment marker located in the microlens array area. An undesired distribution is generated in the size of the plating layer grown from the opening. On the other hand, for those with larger intervals,
The influence of the current density distribution tends to be small.

Further, when the ratio of the area of the alignment marker opening to the area of the region surrounded by the microlens opening existing around the alignment marker opening becomes 1/2 or more, the current Due to the influence of the density distribution, an unfavorable distribution occurs in the size of the first plating layer located in the microlens array region and the plating layer grown from the alignment marker opening. Therefore, the area ratio is preferably less than 1/2,
As it becomes smaller, the influence of the current density distribution tends to become smaller.

As described above, it is possible to suppress the occurrence of a desired current density distribution in the microlens array region due to the influence of the current density distribution due to the existence of the alignment marker openings during the electroplating process. hand,
It is possible to suppress variations in the size of the hemisphere or the like of the first plating layer located in the microlens array region. As a result, the heights of the first plating layer in the microlens array region and the first plating layer as the alignment marker become substantially uniform. This leads to the apex of the microlens and the alignment marker being in the same plane, which enables accurate alignment.

Electroplating is performed by the following method. Using the plating substrate as a work, it is dipped in a plating solution containing metal ions, an external power supply is connected between the plating substrate and the anode plate, and an electric current is caused to flow to form a first plating layer in the opening. Plating is formed in the opening, and by continuing the plating, the first
The first plating layer also spreads on the mask layer of 1 to form a hemispherical structure. The diameter of the lens formed by the microlens array mold to be produced is from several μm to several tens.
It is in the range of 0 μm, and therefore the size of the opening needs to be smaller than the desired diameter of the microlens. In order for plating growth to become isotropic, the size of the opening should be small compared to the diameter or width of the hemispherical structure, etc. The radius of curvature can be reduced by approaching.

The microstructure is formed by depositing metal ions in the plating bath by an electrochemical reaction.
In electroplating, the thickness of the first plating layer can be easily controlled by controlling the plating time and the plating temperature. The main plating metals are Ni and A for single metals.
There are u, Pt, Cr, Cu, Ag, Zn, etc., and in alloys, Cu-Zn, Sn-Co, Ni-Fe, Zn-Ni.
Etc. Although other electroplatable materials can be used, a material that does not form an alloy layer with the electrode layer is preferable. The above also applies to electrodeposition. The electrodeposition liquid includes an electrodeposition liquid of an electrodeposition organic compound (anion type electrodeposition acrylic resin, cation type electrodeposition epoxy resin, etc.).

In the first plating layer formed here, the peripheral portion of the array grows larger than the central portion. This is because the current distribution is not uniform and the current concentrates at the end portions of the electrodes. Therefore, by forming the microlens opening group area wider than the desired microlens array area (that is, the usage area), the area of the first plating layer that grows excessively larger than the central area is desired. Will be outside the microlens array area.

Subsequently, the first plating layer at the peripheral portion of the array, which has grown excessively larger than the central portion, is removed by selective etching in the following manner, whereby the first plating layer having a substantially uniform height is formed. An array of plated layers can be obtained.

In the typical method, the first mask layer is first removed. Next, the 1st grown to a nearly uniform size
A second mask layer is formed on the desired microlens array area including the plating layer and the alignment marker area. As the second mask layer, either an inorganic material or an organic material can be used, but a material having resistance to an etching solution in a later step is used. As a method for forming the second mask layer, a thin film forming method such as a vacuum vapor deposition method, a spin coating method or a dipping method is used. A semiconductor photolithography process and etching are used to form the second mask layer only in the selected region. Here, if a photoresist is used as the second mask layer, the etching step can be omitted.

Although it is not necessary to remove the first mask layer before forming the second mask layer, the removal of the first mask layer improves the adhesion of the second mask layer to the substrate. In particular, when both the first mask layer and the second mask layer are photoresists, the effect of improving the adhesion is great.

Next, the first plating layer exposed from the second mask layer is removed by etching. As the etching method, dry etching or wet etching is used.
As the etching gas and the etching solution, those which do not etch the second mask layer, the electrode layer, and the substrate but selectively etch the first plating layer exposed from the second mask layer are used.

In contrast to the case of forming the first plating layer, electrolytic etching may be used by connecting the cathode and the anode and passing a current from an external power source (this can be used in the case of an electrodeposition layer). Absent). As a result, the first plating layer exposed from the second mask layer is selectively removed by electrolytic etching. Here, if the electrode layer is a material that is not electrolyzed by the plating solution and does not form an alloy layer with the first plating layer, a flat surface of the electrode layer is obtained after electrolytic etching.
Similarly, for the first plating layer, a flat surface of the electrode layer can be obtained if the material does not form an alloy layer with the electrode layer. The metal of the first plating layer removed here can be recovered in the plating solution or the metal plate of the counter electrode, and even an expensive metal material can be used without waste.

The first plating layer in the microlens array area covered with the remaining second mask layer has a substantially uniform size and has a hemispherical structure having a small in-plane distribution of diameter or width. It becomes an array. Also, the first plating layer as the alignment marker can be left because it was covered with the second mask layer.

Further, according to this method, a plurality of second substrates are provided in the substrate.
By providing the mask layer of, a plurality of or a plurality of types of alignment markers and
It is also possible to obtain a mold for a microlens array having a small in-plane distribution of the size of the plating layer. This is because after forming the first plating layer, a region having a small in-plane distribution of the size of the first plating layer excluding the peripheral portion of the array pattern and a region of the first plating layer as an alignment marker are selected. This is because it is possible to form the second mask layer.

Next, the second mask layer is removed, and a second plating layer or electrodeposition layer is formed from the first plating layer to the electrode layer (also represented by the plating layer here). The method of forming the second plating layer may be either electroplating or electroless plating, but by using electroless plating, a microlens array mold having high gloss can be obtained. Furthermore, since this is isotropic plating growth, the radius of curvature of each plating layer in the microlens array area can be made equal in the diagonal and horizontal directions, and the height and alignment of the plating layer in the microlens array area can be made equal. The heights of the plated layers of the markers can be formed to be almost equal.

As a result, the first plating layer is firmly fixed on the electrode layer, the first plating layer can be prevented from falling off in the subsequent steps, and the durability of the microlens array mold can be improved. .

The height of the plating layer in the microlens array region obtained by these and the height of the plating layer of the alignment marker are substantially equal. Therefore, the height of the lens apex of the microlens array obtained from this and the height of the apex of the alignment marker are substantially equal. As a result, when bonding to a drive substrate, etc., the lens vertex of the microlens array and the vertex of the alignment marker are in substantially the same plane, and both are within the focal depth of the lens system on the aligner side. Positioning can be realized.

The mold for the microlens array is obtained by forming the mold material on the mold master for the microlens array (original plate), and then peeling the mold (depending on the material of each part, the above-mentioned structure). Can be used as is as a microstructure array such as a microlens array). Since the mold for the microlens array can be formed directly from the original plate formed by electroplating, it does not require expensive equipment and can be manufactured at low cost. As a peeling method, the original plate and the substrate may be mechanically peeled. However, if it is enlarged, it may be deformed at the time of peeling. Therefore, a method of sequentially etching and removing the substrate, the mask layer, the first plating layer and the like from the back surface may be adopted.

When the mold is formed after providing the sacrificial layer on the substrate and the second plating layer, the mold and the substrate can be separated by removing the sacrificial layer. In this case, the material of the sacrificial layer is selected so that the mold is not corroded by the etchant for etching the sacrificial layer. When the first and second plated layers and the substrate are not corroded by the etchant that etches the sacrificial layer, the substrate on which the plated layer is formed can be used as an original plate a plurality of times. When the original plate becomes unusable due to scratches, stains, etc. after being used a plurality of times, a mold master may be prepared by the same method.

As the material of the mold for the microlens, any material such as resin, metal and insulator can be used as long as it can be formed on a substrate having a plated layer and can be peeled off. As a simple method of forming a mold, a molten or dissolved solution of resin, metal, or glass is applied on a substrate on which a plating layer is formed, and after this is cured, peeling is performed by the above-described peeling method. . In this case, as the die material, a material that does not alloy the substrate or the plating layer is selected. As another method, a metal mold is electroplated on the plating layer and the electrode layer using the substrate as a cathode. If a sacrificial layer is used, a mold electrode layer is formed on the sacrificial layer, and electroplating is performed using the mold electrode layer as a cathode.

Further, a microlens array can be formed by forming a material to be a microlens on the microlens array mold and then peeling it off. This makes it possible to easily manufacture microlenses having the same shape at low cost.
As a material for the microlens, a material that is easily peelable from the microlens mold is used. When a resin is used as the microlens material, a light-transmissive thermosetting resin, an ultraviolet curable resin, an electron beam curable resin, etc. are applied on the mold for the microlens array and then cured by ultraviolet light irradiation, electron beam irradiation, etc. Let Prevent air bubbles from forming during curing. When applying the resin, it is preferable to perform deaeration.

After curing, the resin is peeled off from the mold to form a microlens array. As the resin forming the microlens array, a material that can transmit light in the wavelength region of light used by the light receiving or light emitting device using the microlenses is used. In the case of producing a microlens by the above method, alkali glass is not indispensable, and restrictions on materials for the microlens and the supporting substrate can be reduced as compared with the ion exchange method. If molten glass is used instead of resin, a glass microlens array can be produced.

Of course, the mold of the present invention is not limited to the microlens array, as long as it is applicable, and can be used for manufacturing any structure.

[0057]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments and examples of the present invention will be described in detail below with reference to the drawings.

(First Embodiment) A first embodiment will be described with reference to the manufacturing process diagrams of FIGS. In this embodiment, a 4-inch φ silicon wafer having a 1 μm thick silicon dioxide film formed on both sides by thermal oxidation using an oxidizing gas is used as the substrate 1 shown in FIG. This wafer has a thin film forming method 1
50 and 50% of Ti and Pt respectively by the vacuum sputtering method.
Å and 500Å are continuously formed to form the electrode layer 2. A positive photoresist (Az1500: manufactured by Client Co.) is applied on top of this to form a first mask layer 3.

Next, the photoresist is exposed and developed by photolithography to expose the electrode layer 2 according to a predetermined pattern, and the opening 4 for the microlens array is formed. The individual microlens array openings 4 have a circular shape and are provided in an array shape (in this embodiment, at equal intervals in the left and right, and up and down) within a region of 95 mmφ in the surface of the silicon wafer. The diameter is 5 μm, and the space between the adjacent microlens array openings 4 is 18 μm (see FIG. 1A). At the same time, a plurality of rectangular alignment marker openings 5 having a short side width of 5 μm and a length of 37 μm are provided at positions corresponding to the alignment markers (see FIG. 2).

The interval where the alignment marker opening 5 is closest to the microlens opening 4 is 20 μm. At this time, the ratio of the area of the alignment marker opening 5 to the area of the region surrounded by the microlens opening 4 existing around the alignment marker opening 5 is 1/10.

Then, using the substrate 1 as a work, the electrode layer 2 as a cathode, and a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid and a brightening agent, a bath temperature of 50 ° C. and a cathode current without stirring were used. Ni plating is performed at a density of 40 A / dm ² . The first plating layer 6 made of Ni is first deposited and grown from the opening 4 for the microlens array, and the first plating layer 6 also spreads on the first mask layer 3. Thus, the radius of the first plating layer 6 at the center of the array is about 10
The first plating layer 6 is grown until a semi-spherical structure of μm is formed (FIG. 1 (b) is a cross-sectional view and FIG. 3 is a top view). When the radius of the first plating layer 6 was about 10 μm at the center of the array, the first plating layer 6 having a maximum radius of about 15 μm was formed at the periphery of the array.

Next, the first mask layer 3 is removed with acetone and N, N-dimethylformamide. Then, a positive photoresist (AzP4620: manufactured by Client Co.) was applied, exposed and developed to remove the peripheral portion of the array 1064 ×.
The second mask layer 7 is selectively provided on the 808 regions and the first plating layer 6 grown at the positions corresponding to the alignment markers. As a result, the first plating layer 6 in the peripheral portion of the array is exposed (FIG. 1C is a cross-sectional view and FIG. 4 is a top view). Here, the opening 5 provided for the alignment marker has almost no effect on the current density distribution, and the in-plane distribution of the diameter of the first plating layer 6 in the area covered with the second mask layer 7 is 5%. It was within.

Then, using the substrate 1 as a work, and using it as an anode, a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid, and a brightener was used, and the bath temperature was 60 ° C.
The exposed first plating layer 6 is electrolytically etched at an anode current density of 8 A / dm ² (FIG. 1D is a sectional view, FIG.
5 is the top view). Here, since Pt was used as the electrode layer 2, the electrode layer was not corroded. Then, the electrolytic etching was stopped when the first plating layer 6 made of Ni existing in the region not covered with the second mask layer 7 was consumed.

Next, the second mask layer 7 is removed with acetone and N, N-dimethylformamide to obtain 106
An array of 4 × 808 first plating layers 6 and alignment markers 9 are formed (FIG. 1E is a sectional view and FIG. 6 is a top view). At this time, the in-plane distribution of the radius of the first plating layer 6 was within 5%.

Next, an electroless Ni plating solution (Alnick CT, manufactured by Pax Co.) containing a reducing agent for hypophosphite was used to perform Ni electroless plating at a bath temperature of 90 ° C. to obtain a second plating layer. 8 is formed (FIG. 1D is a sectional view, and FIG. 7 is a top view). As a result, the first plating layer 6 is firmly fixed on the electrode layer 2, and by using electroless plating for forming the second plating layer, a mold for a microlens array having high gloss can be obtained. In addition, the radius of curvature of each plating layer in the diagonal direction and the horizontal direction is substantially equal, the average radius of curvature is 20 μm, the distribution of the radius of curvature is within ± 1 μm, and a mold master having a uniform shape can be formed. . Furthermore, the in-plane distribution of the height of the plating layer corresponding to the microlens group and the plating layer corresponding to the alignment marker 9 was within 5%.

As described above, according to the present embodiment, a method of manufacturing a mold for a microlens array having an alignment marker that can easily reduce the in-plane distribution of the size of each lens and realizes highly accurate alignment is realized. We were able to.

Next, a method for manufacturing a microlens array mold using the above structure as a mold master will be described.

An electroforming mold release agent is applied onto the mold master. Using this substrate as a cathode and a Ni plating bath consisting of nickel sulfamate, nickel bromide, boric acid and a brightening agent, Ni at a bath temperature of 50 ° C. and a cathode current density of 5 A / dm ² was used.
Electroplating is performed to form a mold. Then, the mold is released from the substrate to form a microlens array mold.

A method of manufacturing a convex microlens array using this mold will be described. After applying an ultraviolet curable resin to the microlens array mold, a glass substrate to be a supporting substrate is placed thereon. This resin is cured by irradiation with ultraviolet rays and then peeled off to manufacture a convex microlens array. This convex microlens array was equipped with an alignment marker that realizes highly accurate alignment, and the in-plane distribution of the lens diameter was within 5%.

Subsequently, the markers of the convex microlens array were attached to the markers formed on the TFT liquid crystal substrate, and the microlenses could be accurately arranged at the positions corresponding to the pixels. . When these were connected to a drive circuit and driven as a liquid crystal projector, incident light was condensed by a microlens and a bright display image could be obtained.

(Second Embodiment) Also in the second embodiment, as in the first embodiment, thermal oxidation is performed using an oxidizing gas, and both surfaces are 1 μm thick.
A 4-inch φ silicon wafer having a thick silicon dioxide film formed thereon is used as the substrate 1. On this wafer, Ti and Pt are continuously formed into a film of 50 Å and 500 Å, respectively, by a vacuum sputtering method, which is one of the thin film forming methods, to form the electrode layer 2. A positive photoresist (Az1500: manufactured by Client Co.) is applied on top of this to form the first mask layer 3. Next, the photoresist is exposed and developed by photolithography to expose the electrode layer 2, and the microlens array opening 4 is formed. The openings have a circular shape and are provided in an array form within a region of 95 mmφ in the surface of the silicon wafer. Its diameter is 5 μm and the distance between adjacent openings is 18 μm. At the same time, the width corresponding to the alignment marker is 5 μm and the inner diameter is 56 μm.
A few ring-shaped alignment marker openings 5 are provided at several locations (Fig. 8). This is a feature of this embodiment.

The distance at which the alignment marker opening 5 is closest to the microlens opening 4 is 30 μm. At this time, the microlens openings 4 existing around the alignment marker openings 5 are also provided.
The ratio of the area of the alignment marker opening 5 to the area of the region surrounded by is 3/40.

Next, using this substrate 1 as a work,
Using the electrode layer 2 as a cathode, a Ni plating bath composed of nickel sulfate, nickel chloride, boric acid and a brightener is used to perform Ni plating at a bath temperature of 50 ° C. and a cathode current density of 40 A / dm ² without stirring. The first plating layer 6 made of Ni is first deposited and grown from the opening 4 for the microlens array,
The first plating layer 6 also spreads on the mask layer 3 of FIG. In this way, the first plating layer 6 is grown until it becomes a hemispherical structure having a radius of the central portion of the array of about 10 μm (FIG. 9). When the radius of the first plating layer 6 is about 10 μm in the central part of the array, the maximum radius is about 15 μm in the peripheral part 5 of the array.
The first plated layer 6 was formed.

Next, the first mask layer 3 is removed with acetone and N, N-dimethylformamide. Then, a positive photoresist (AzP4620: manufactured by Client Co.) was applied, exposed and developed to remove the peripheral portion of the array 1064.
The second mask layer 7 is selectively provided on the first plating layer 6 grown at the position corresponding to the × 808 regions and the alignment marker. Here, the opening 5 provided for the alignment marker has almost no effect on the current density distribution,
The in-plane distribution of the diameter of the first plating layer 6 in the area covered with the second mask layer 7 was within 5%.

Subsequently, using the substrate 1 as a work, using it as an anode, and using a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid and a brightener, the bath temperature was 60 ° C. and the anode current density was 8 A / dm ² . , Exposed first plating layer 6
Electrolytic etching is performed. Here, P is used as the electrode layer 2.
The electrode layer was not corroded because t was used.
Then, the electrolytic etching was stopped when the first plating layer made of Ni existing in the region not covered by the second mask layer 7 was consumed.

Next, the second mask layer 7 is removed with acetone and N, N-dimethylformamide to obtain 106
An array of 4 × 808 first plating layers 6 and a ring-shaped alignment marker can be formed. At this time, the in-plane distribution of the radius of the first plating layer 6 was within 5%.

Next, an electroless Ni plating solution (Alnick CT, manufactured by Pax Co.) containing a reducing agent for hypophosphite is used to perform Ni electroless plating at a bath temperature of 90 ° C. to obtain a second plating layer. Forming eight. As a result, the first plating layer 6 was firmly fixed on the electrode layer, and by using electroless plating for forming the second plating layer, a microlens array mold having high gloss was obtained. Further, the radius of curvature of each plating layer in the diagonal direction and the horizontal direction is almost equal, the average radius of curvature is 20 μm, the distribution of the radius of curvature is within ± 1 μm, and a mold master having a uniform shape is formed. did it. Furthermore, the in-plane distribution of the height of the plating layer corresponding to the microlens group and the plating layer corresponding to the alignment marker is 5%.
It was within.

As described above, also according to this embodiment, a mold for a microlens array having a ring-shaped alignment marker that can easily reduce the in-plane distribution of the size of each lens and realizes highly accurate alignment can be obtained. The manufacturing method could be realized.

As described in the first embodiment, the mold is used as a master to form a mold for a microlens array, and then a convex microlens array 15 can be manufactured. This convex microlens array is equipped with alignment markers that realize highly accurate alignment.
Furthermore, the in-plane distribution of the lens diameter was within 5%.

(Third Embodiment) In the third embodiment as well, similar to the first embodiment, a 4-inch φ silicon wafer having a 1 μm thick silicon dioxide film formed on both surfaces by thermal oxidation using a gas is prepared. Used as the substrate 1. 50 and 50% of Ti and Pt were formed on this wafer by vacuum sputtering, which is one of the thin film forming methods.
Å and 500Å are continuously formed to form the electrode layer 2. On top of that, a positive photoresist (Az1500: Hoe
chst) to form the first mask layer 3. Next, the photoresist is exposed and developed by photolithography to expose the electrode layer 2, and the microlens array opening 4 is formed. The openings 4 have a circular shape and are provided in an array in a region of 95 mmφ in the surface of the silicon wafer. Its diameter is 5 μm, and the distance between adjacent openings 4 is 18 μm. At the same time, at the position corresponding to the alignment marker, the short side width is 5 μm and the length is 3
A rectangular opening having a size of 7 μm and a ring-shaped opening having a width of 5 μm and an inner diameter of 56 μm are provided at several places (see FIG. 10).

The distance at which the alignment marker opening 5 is closest to the microlens opening 4 is 20 μm. Further, at this time, the microlens opening 4 existing around the alignment marker opening 5 is formed.
The ratio of the area of the alignment marker opening to the area of the region surrounded by is 7/80.

Using this substrate 1 as a work, the electrode layer 2
As a cathode, and using a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid, and a brightener, the bath temperature without stirring
Ni plating is performed at 50 ° C. and a cathode current density of 40 A / dm ² . The first plating layer 6 made of Ni is first deposited and grown from the opening 4 for the microlens array, and the first plating layer 6 also spreads on the first mask layer 3. In this way, the first plating layer 6 is grown until it becomes a hemispherical structure having a radius of the central portion of the array of about 10 μm. When the radius of the first plating layer 6 was about 10 μm at the center of the array, the first plating layer 6 having a maximum radius of about 15 μm was formed at the periphery of the array (FIG. 10).

Next, the first mask layer 6 is removed with acetone and N, N-dimethylformamide. Then, a positive photoresist (AzP4620: manufactured by Client Co.) was applied, exposed and developed to remove the peripheral portion of the array 1064 ×.
A second mask layer 7 is selectively provided on the 808 regions and the first plating layer 6 grown at the positions corresponding to the alignment markers. Here, the opening 5 provided for the alignment marker has almost no effect on the current density distribution, and the in-plane distribution of the diameter of the first plating layer 6 in the area covered with the second mask layer 7 is 5%. It was within.

Then, using this substrate 1 as a work,
Using it as an anode, a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid and a brightener was used, and the bath temperature was 60
The exposed first plated layer 6 is electrolytically etched at a temperature of 8 ° C. and an anode current density of 8 A / dm ² . Here, the electrode layer was not corroded by using Pt as the electrode layer 2. Then, the electrolytic etching was stopped when the first plating layer 6 made of Ni existing in the region not covered with the second mask layer 7 was consumed.

Next, the second mask layer 7 is removed with acetone and N, N-dimethylformamide to obtain 106
It was possible to form an array of 4 × 808 first plating layers 6 and alignment markers corresponding to a ring shape and a cross shape. At this time, the in-plane distribution of the radius of the hemispherical structure is 5
It was within%.

Next, an electroless Ni plating solution (Alnick CT, manufactured by Pax Co.) containing a reducing agent for hypophosphite was used to perform Ni electroless plating at a bath temperature of 90 ° C. to obtain a second plating layer. Forming eight. As a result, the first plating layer 6 was firmly fixed on the electrode layer 2, and the electroless plating was used to form the second plating layer, whereby a mold for a microlens array having a high gloss was obtained (Fig. 11). Further, the radius of curvature of each plating layer in the diagonal direction and the horizontal direction is substantially equal, the average radius of curvature is 20 μm, and the distribution of the radius of curvature is ± 1 μm.
It was possible to form a mold master having a uniform shape and having a size of m or less. Furthermore, the in-plane distribution of the height of the plating layer corresponding to the microlens group and the plating layer corresponding to the alignment marker was within 5%.

As described above, according to the present embodiment, the microlens array having the alignment markers corresponding to the ring shape and the cross shape, which can easily reduce the in-plane distribution of the size of each lens and realize the highly accurate alignment, can be obtained. It was possible to realize the manufacturing method of the mold for use.

As described in the first embodiment, the mold is used as a master to form a mold for a microlens array, and then a convex microlens array 15 can be manufactured. This convex microlens array is equipped with alignment markers that realize highly accurate alignment.
Furthermore, the in-plane distribution of the lens diameter was within 5%.

(Fourth Embodiment) In the fourth embodiment, a 5-inch φ silicon wafer having a 1 μm thick silicon dioxide film formed on both sides by thermal oxidation using an oxidizing gas is used as a substrate. Ti and Pt are respectively 50Å and 500Å by vacuum sputtering which is one of the thin film forming methods on this wafer.
The film is continuously formed to form the electrode layer 2. A positive photoresist (Az1500: manufactured by Client Co.) is applied on top of this to form a first mask layer 3. Next, the photoresist is exposed and developed by photolithography to expose the electrode layer 2, and the microlens array opening 4 is formed.
To form. The openings 4 have a circular shape and are provided in an array within a 120 mmφ area on the surface of the silicon wafer. Its diameter is 5 μm and the space between adjacent openings is 18
μm. At the same time, several rectangular openings 5 each having a width of 5 μm and a length of 37 μm and several ring-shaped openings 5 having a width of 5 μm and an inner diameter of 56 μm are provided at arbitrary positions corresponding to the alignment marker. At this time, the ratio of the alignment marker opening area to the area of the region surrounded by the microlens opening 4 existing around the alignment marker opening 5 is 21/80.

Using this substrate 1 as a work, the electrode layer 2
As a cathode, and using a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid, and a brightener, the bath temperature without stirring
Ni plating is performed at 50 ° C. and a cathode current density of 40 A / dm ² . The first plating layer 6 made of Ni is first deposited and grown from the opening 4 for the microlens array, and the first plating layer 6 also spreads on the first mask layer 3. In this way, the first plating layer 6 is grown until it becomes a hemispherical structure having a radius of the central portion of the array of about 10 μm. When the radius of the hemispherical structure was about 10 μm at the center of the array, a hemispherical structure having a maximum radius of about 15 μm was formed at the periphery of the array.

Next, the first mask layer is removed with acetone and N, N-dimethylformamide. Then, a positive photoresist (AzP4620: manufactured by Client Co., Ltd.) was applied, exposed, and developed.
The second mask layer 7 is selectively provided on the first plating layer 6 grown at the positions corresponding to the 64 × 808 regions and the eight sets of alignment markers corresponding to the respective regions. Here, there is almost no influence on the current density distribution by the opening 5 provided for the alignment marker, and 1064 × 8
The first of the regions covered with the second mask layer 7 of the 08 regions
The in-plane distribution of the diameter of the plating layer 6 was within 5%.

Using this substrate 1 as a work, using it as an anode, and using a Ni plating bath consisting of nickel sulfate, nickel chloride, boric acid and a brightening agent, exposed at a bath temperature of 60 ° C. and an anode current density of 8 A / dm ² . The electrolytic etching of the first plated layer 6 is performed. Here, the electrode layer was not corroded by using Pt as the electrode layer 2. And
The electrolytic etching was stopped when the first plating layer 6 made of Ni existing in the region not covered with the second mask layer 7 was consumed.

Next, by removing the second mask layer 7 with acetone and N, N-dimethylformamide, an array of 1064 × 808 first plating layers 6 at eight locations,
Eight sets of alignment markers could be formed.
At this time, the in-plane distribution of the radius of the first plating layer 6 at each location was within 5%.

At this time, since the respective alignment markers are the respective markers of the first to third embodiments and the combination thereof, they are different alignment markers.

Next, electroless Ni plating solution (Alnick CT, manufactured by Pax Co.) containing a reducing agent for hypophosphite was used to perform Ni electroless plating at a bath temperature of 90 ° C. to obtain a second plating layer. Forming eight. As a result, the first plating layer 6 was firmly fixed on the electrode layer 2, and by using electroless plating for forming the second plating layer, a mold for a microlens array having high gloss was obtained. In addition, the radius of curvature of each plating layer in the diagonal direction and the horizontal direction is substantially equal, the average radius of curvature is 20 μm, the distribution of the radius of curvature is within ± 1 μm, and a die having a uniform shape can be formed. . Furthermore, the in-plane distribution of the height of the plating layer corresponding to the microlens group and the plating layer corresponding to the alignment marker was within 5%.

As described above, according to this embodiment, a method of manufacturing a mold for a microlens array having an alignment marker that can easily reduce the in-plane distribution of the size of each lens and realizes highly accurate alignment is realized. We were able to.

Next, a mold releasing agent for electroforming is applied onto the mold master manufactured by the above method. This substrate is the cathode,
Using a Ni plating bath composed of nickel sulfamate, nickel bromide, boric acid and a brightener, Ni electroplating is performed at a bath temperature of 50 ° C. and a cathode current density of 5 A / dm ² to form a mold. Then, the mold is released from the substrate to form a microlens array mold.

After applying the ultraviolet curable resin 12 to this mold for microlens array, a glass substrate to be the supporting substrate 13 is placed thereon. After this resin is cured by UV irradiation, it is peeled off and cut off,
A convex microlens array 15 equipped with various kinds of alignment markers 9 can be produced (FIG. 12). The mylo lens array was equipped with the alignment marker 9 that realizes highly accurate alignment, and the in-plane distribution of the lens diameter was within 5%.

[0099]

As described above, according to the present invention,
Easy fabrication process, high controllability, small radius of curvature and small in-plane distribution in the array can be realized, more accurate alignment can be achieved, and cross alignment marker can be applied A microstructure array mold capable of producing a microstructure array equipped with an alignment marker could be realized. Furthermore, a microstructure array such as a microlens array having an alignment marker that has a small radius of curvature and a small in-plane distribution in the array, realizes highly accurate alignment, and is compatible with a cross-shaped alignment marker, and the same. The manufacturing method could be realized.

Further, it is possible to form a plurality of molds for a microstructure array such as a microlens array in which the variation in the size of the microstructure such as a lens is suppressed within one substrate surface. . Since the height of the apex of the microlens array and the height of the apex of the alignment marker obtained from these microlens array molds are in substantially the same plane and both come within the depth of focus of the lens system on the aligner side, Highly accurate alignment can be achieved. As a result, it is possible to improve the overlay accuracy with the TFT substrate and the like, improve the matching between the pixel portion and the microlens, and improve the pixel aperture ratio and the light collection rate of the microlens.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a manufacturing process of a mold for a microlens array according to a first embodiment of the present invention.

FIG. 2 is a top view of step (a) of FIG.

FIG. 3 is a top view of step (b) of FIG.

FIG. 4 is a top view of step (c) in FIG.

FIG. 5 is a top view of step (d) in FIG.

FIG. 6 is a top view of step (e) in FIG.

FIG. 7 is a top view of step (f) in FIG.

FIG. 8 is a top view showing a part of the manufacturing process of the mold for the microlens array according to the second embodiment of the present invention.

FIG. 9 is a top view showing a part of the manufacturing process of the mold for the microlens array according to the second embodiment of the present invention.

FIG. 10 is a top view showing a part of the manufacturing process of the mold for the microlens array according to the third embodiment of the present invention.

FIG. 11 is a top view showing a part of the manufacturing process of the mold for the microlens array according to the third embodiment of the present invention.

FIG. 12 is a top view showing a mold for a microlens array according to a fourth embodiment of the present invention.

[Explanation of symbols]

1 substrate 2 electrode layers 3 First mask layer 4 Microlens array opening 5 Alignment marker opening 6 First plating layer 7 Second mask layer 8 Second plating layer 9 Alignment marker

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B29C 33/38 G02B 3/00

Claims (28)

(57) [Claims] 1. A substrate having a conductive portion is used, (1) a step of forming an insulating first mask layer on the conductive portion, (2) a desired microstructure on the first mask layer. Forming a plurality of microstructure openings at intervals corresponding to the array arrangement and forming alignment marker openings in the same process; (3) electroplating or electrodeposition using the conductive portion as a cathode And a step of forming a first plating layer or an electrodeposition layer on the microstructure opening, the alignment marker opening, and the first mask layer through the opening. The opening for the alignment marker in the step (2) is separated from the recent opening for the microstructure by one pitch or more, which is the maximum pitch of the opening for the microstructure, and A microstructure array characterized in that the ratio of the area of the alignment marker opening to the area of the region surrounded by the microstructure opening existing around the alignment marker opening is smaller than 1/2. Of manufacturing. 2. The method for manufacturing a microstructure array according to claim 1, further comprising the step of (4) removing the first mask layer. 3. A step (5) of forming a second mask layer on a desired microstructure array region and an alignment marker region of the substrate and the first plating layer or electrodeposition layer, (6) 6. The method according to claim 1, further comprising a step of removing the first plating layer or the electrodeposition layer in a region where the second mask layer is not formed by etching, and (7) a step of removing the second mask layer. 1. The method for producing a microstructure array according to 1 or 2. 4. The method further comprises the step (8) of forming a second plating layer or electrodeposition layer from the first plating layer or electrodeposition layer to the conductive portion or the first mask layer. The method for producing a microstructure array according to claim 1, 2 or 3. 5. In the step (2), the diameter or width (short side) of the alignment marker opening is equal to or less than the diameter or width of the microstructure opening. Item 5. A method for manufacturing a microstructure array according to any one of Items 1 to 4. 6. The method for producing a microstructure array according to claim 1, wherein the alignment marker opening in the step (2) includes a square opening. 7. The method for producing a microstructure array according to claim 1, wherein in the step (2), the alignment marker opening includes a rectangular opening. 8. The method for producing a microstructure array according to claim 1, wherein the alignment marker openings in the step (2) include polygonal openings. 9. The method for producing a microstructure array according to claim 1, wherein in the step (2), the alignment marker opening includes a ring-shaped opening. 10. The method for producing a microstructure array according to claim 1, wherein in the step (2), the microstructure openings are circular. 11. The method for producing a microstructure array according to claim 1, wherein in the step (2), the microstructure openings are slit-shaped. 12. The microstructure array according to claim 1, wherein in the step (2), the openings for microstructures are arranged at equal intervals in the left-right direction and the up-down direction. Manufacturing method. 13. The method according to claim 3, wherein in the step (4), the heights of the first plating layer and the electrodeposition layer in the region covered with the second mask layer are substantially equal. A method for producing a microstructure array according to item 1. 14. In the step (4), the in-plane distribution of the height of the first plating layer or the electrodeposition layer in the region covered with the second mask layer is within 5%. Item 3
13. The method for manufacturing a microstructure array according to any one of 1 to 12. 15. The method for producing a microstructure array according to claim 3, wherein in the step (6), the first plating layer is removed by electrolytic etching. 16. The method for producing a microstructure array according to claim 4, wherein in the step (8), the second plating layer is formed by electroless plating. 17. The microstructure array is a mold for a microstructure array, and the microstructure array is a mold.
A method for producing a microstructure array according to any one of 1. 18. A mold for a microstructure array is a mold for a microlens array.
A method for producing a microstructure array according to item 1. 19. A microstructure array manufactured by the method for manufacturing a microstructure array according to claim 1, wherein the microstructure array is outside the microstructure group of the microstructure array. Plating layer or electrodeposition layer, or first plating layer or electrodeposition layer and first plating layer or electrodeposition layer and electrode layer or first mask layer formed on the first mask layer
In the structure for the alignment marker comprising the second plating layer or the electrodeposition layer, there is no flat portion between the closest points of the adjacent first plating layer or the electrodeposition layer or the second plating layer or the electrodeposition layer. Microstructure array. 20. The alignment marker structure comprises a rod-shaped first plating layer or electrodeposition layer or first and second rod layers.
20. The microstructure array according to claim 19, wherein the microstructure array includes a single body or an aggregate thereof including the plating layer or the electrodeposition layer. 21. The structure for an alignment marker includes a ring-shaped first plating layer or electrodeposition layer or a single body or an assembly of the first and second plating layers or electrodeposition layers. 20. The microstructure array according to claim 19. 22. The microstructure array according to claim 19, 20 or 21, wherein the heights of the microstructure and the alignment marker structure are substantially equal to each other. 23. The microstructure array according to claim 19, 20 or 21, wherein the distribution of heights of the microstructure and the structure for the alignment marker is within 5%. 24. The microstructure array according to claim 19, wherein all or part of the cross-sectional shape of the alignment marker structure is a curved shape or a semicircular shape. . 25. The microstructure array according to any one of claims 19 to 24, which is a mold for a microstructure array. 26. The microstructure array according to claim 25, which is a mold for a microlens array. 27. A microstructure array configured as the microlens array according to any one of claims 19 to 24, or a microlens array produced by the mold for a microlens array according to claim 26, An image pickup device, wherein each microlens is mounted in alignment with each light receiving portion using the alignment marker. 28. A microstructure array configured as the microlens array according to any one of claims 19 to 24, or a microlens array produced by the mold for a microlens array according to claim 26, A display device in which each microlens is mounted in alignment with each pixel portion using the alignment marker.