JP2003149423A - Microfabrication method for optical element, method for manufacturing base material, and base material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical element microfabrication method capable of preventing the processing accuracy of each manufacturing process of a base material from being reduced by accurately recognizing the position of the base material and capable of easily recognizing the position, and to provide a base material manufacturing method and the base material. SOLUTION: The base material manufacturing method for manufacturing the base material by machining it by a machine device has a process for forming a specific shape on the base material by relatively moving a cutting tool of the machine device for machining the base material to the machined surface of the base material held by a rotating/holding member for rotating/ holding the base material and a process for forming a 1st position regonition part to be a reference for position recognition on the base material in a state that a rotation center axis for rotating the base material held on the rotating/ holding member is not moved after forming the specific shape on the base material. Since the rotation center position of the base material can be easily calculated by the 1st position recognition part, axial slippage can be prevented and the marching accuracy of each manufacturing constitution can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element microfabrication method, a substrate manufacturing method, and a substrate, and more particularly to a substrate having a curved surface to which added value is added through a plurality of manufacturing steps. The present invention relates to a mark serving as a positioning reference that can maintain the positioning accuracy of a processing position with high accuracy between a plurality of processes.

[0002]

2. Description of the Related Art Recently, as an information recording medium, for example, C
D, DVD and the like are widely used, and many optical elements are used in precision equipment such as a reading device that reads these recording media. From the viewpoint of cost reduction and miniaturization, optical elements used in these devices, such as optical lenses, often use resin optical lenses rather than glass optical lenses. Such a resin optical lens
It is manufactured by general injection molding, and a molding die for injection molding is also formed by general cutting.

By the way, recently, the specifications and performance itself required for an optical element have been improved. For example, when manufacturing an optical element having a diffractive structure or the like on its optical function surface, the optical element is injection molded. In order to do so, it is necessary to form a surface for giving such a diffractive structure to the molding die.

In manufacturing such an optical element, for example, a step of processing a base material as a base material, a step of forming a desired pattern (eg, a diffraction grating shape) on the processed base material, a pattern It is necessary to perform stepwise a step of forming a molding die by performing various treatments on the base material on which is formed.

[0005]

By the way, in each of a plurality of manufacturing processes, it is general to use a dedicated device for carrying out each process. When processing, it is necessary to accurately position the substrate.

However, conventionally, no measures have been taken to accurately perform positioning, and a base material to which added value is added through a plurality of manufacturing processes,
There is a problem in that the machining positioning accuracy cannot be maintained with high accuracy between a plurality of processes.

In particular, in the case of performing precision processing of submicron order or less such as forming a diffraction grating on an optical element, it may be assumed that a detection accuracy within ± several tens nm is required. .

In such a case, a reference point for calculating the reference coordinate system is required in the electron beam drawing process for forming a desired drawing pattern on the substrate, and this reference point cannot be detected with high accuracy. As a result, the drawing processing accuracy of the drawing pattern also decreases.

Further, in order to prevent the optical axis of the optical element from being displaced, the positional deviation of the central axis of the optical element needs to be within several μm, but the conventional method can eliminate the positional deviation. There wasn't.

Although it is conceivable to form a positioning mark on the base material, when the mark is formed by cutting, a step of the cutting surface is formed at the edge of the cut line portion. There is a problem that continuous plastic deformation or the like is formed for each bite in the region, it is difficult to identify the edge portion between the cut portion and the non-cut portion, and it is difficult to identify the mark after processing.

The present invention has been made in view of the above circumstances. An object of the present invention is to perform position recognition with high accuracy, while preventing a reduction in processing accuracy in each manufacturing process of a base material. An object of the present invention is to provide a method for finely processing an optical element, a method for manufacturing a base material, and a base material, which can contribute to elimination of misalignment of the central axis of an optical element and the like and can easily perform position recognition.

[0012]

In order to achieve the above object, the invention according to claim 1 is an optical element fine processing method for performing fine processing for an optical element, which comprises rotating a substrate. The first step of forming the base material into a predetermined shape by holding and moving the cutting means relative to the surface of the base material to be processed, and the base in a state where the rotation axis of the base material does not move. A second step of forming a position recognizing unit serving as a position recognizing reference on a material, and placing the base material on a stage of an electron beam drawing apparatus that draws with an electron beam, and detecting the position of the base material by a detection means. A third step of detecting the recognition unit to acquire position coordinates, and performing three-dimensional drawing with an electron beam on the base material based on the acquired position coordinates;
It is characterized by including.

Further, the invention according to claim 2 is characterized in that the position recognizing part includes a first position recognizing part formed substantially concentrically with respect to the rotation center axis.

Further, the invention according to claim 3 is characterized in that the position recognizing section includes a second position recognizing section formed with the first position recognizing section as a reference.

The invention according to claim 4 is the second invention
Based on the position coordinates of the position recognition unit, the drawing is performed three-dimensionally by the electron beam on the base material.

Further, the invention according to claim 5 is the first
Is formed in a concentric circle shape substantially concentric with the rotation center of the base material, and the second step is a step of recognizing the first position recognizing section and a step of recognizing the first position recognizing section. It is characterized by including a step of forming a parallel first line and a step of forming a second line substantially orthogonal to the first line.

The invention according to a sixth aspect is the first aspect.
It is characterized by further comprising a step of forming a substantially cross shape formed by the line and the second line in a number such that the center position of the base material can be calculated over the periphery of the first position recognition unit.

Further, the invention according to claim 7 is characterized in that at least three or more of the substantially cruciform shapes are formed around the periphery of the first position recognizing portion.

The invention according to claim 8 is the second
In the step, the second position recognition part is formed by digging a fine line by using a focused ion beam processing device.

The invention according to claim 9 is the second aspect.
The position recognition part is formed by a line thinner than the first position recognition part.

The tenth aspect of the invention is characterized in that the first position recognizing portion is formed in a shape having different plane directions.

The invention according to claim 11 is characterized in that the first position recognition portion is formed by a line consisting of a bright field and a dark field.

Further, the invention according to claim 12 is characterized in that the first position recognizing part is processed so that the cutting edge of the cutting tool has at least one inflection point.

The invention as set forth in claim 13 is characterized in that the line consisting of the bright field and the dark field is formed by utilizing the unevenness of the cutting edge of the cutting tool.

The invention according to claim 14 is characterized in that the irregularities are formed by abrasion of the cutting edge of the cutting tool.

The invention according to claim 15 is characterized in that the line consisting of the bright field and the dark field has a substantially uneven shape in cross section.

The invention according to claim 16 is characterized in that the unevenness has a step which exceeds the depth of focus of the observation optical system for observing the first position recognizing section.

According to the seventeenth aspect of the present invention, a line in which a plurality of bright fields and a plurality of dark fields are alternately formed is formed by cutting a plurality of times by shifting the position of the cutting edge of the cutting tool. Is characterized by.

The invention according to claim 18 is a method of manufacturing a base material by manufacturing the base material by processing the base material with a processing device, the cutting tool of the processing device for processing the base material. A first step of forming the base material in a specific shape by moving the base material relative to a processed surface of the base material held by a rotation holding member that rotationally holds the base material,
After forming the specific shape on the base material, a first position serving as a reference for position recognition on the base material in a state in which the rotation center axis of the base material held by the rotation holding member does not move.
And a second step of forming the position recognizing part.

Further, the invention according to claim 19 includes a third step of forming a second position recognizing portion which serves as a reference for positioning the base material with the position of the first position recognizing portion as a reference. It is further characterized by having.

According to a twentieth aspect of the present invention, the first position recognizing portion is formed in a concentric circle shape substantially concentric with the rotation center of the base material, and the third step is the first position. It includes a step of recognizing a recognition section, a step of forming a first line substantially parallel to the first position recognition section, and a step of forming a second line substantially orthogonal to the first line. It is characterized by that.

Further, in the invention of a twenty-first aspect, a substantially cross shape formed by the first line and the second line is formed in the first line.
It is characterized by further comprising the step of forming a number that allows calculation of the center position of the base material around the position recognition part.

Further, the invention according to claim 22 is characterized in that at least three or more of the substantially cross shape are formed around the periphery of the first position recognition portion.

The invention according to claim 23 is characterized in that, in the third step, the second position recognizing portion is formed by digging a fine line by using a focused ion beam processing apparatus. .

The invention according to claim 24 is characterized in that the second position recognizing portion is formed by a line thinner than the first position recognizing portion.

Further, in the invention according to claim 25, in the third step, a step of forming a thin film in which carbon is vapor-deposited on the base material, and the second position recognition part by processing the thin film are carried out. And a step of forming.

The invention according to claim 26 is characterized in that the first position recognizing portion is formed in a shape capable of obtaining a regular edge image.

The invention according to claim 27 is characterized in that the first position recognizing portion is formed in a shape having different surface directions.

The invention according to claim 28 is characterized in that the first position recognizing portion is formed by a line consisting of a bright field and a dark field.

The invention according to claim 29 is characterized in that the first position recognizing part is processed so that the cutting edge of the cutting tool has at least one inflection point.

Further, the invention according to claim 30 is characterized in that the line consisting of the bright field and the dark field is formed by utilizing the unevenness of the cutting edge of the cutting tool.

The invention according to claim 31 is characterized in that the irregularities are formed by abrasion of the cutting edge of the cutting tool.

The thirty-second aspect of the present invention is characterized in that the line consisting of the bright field and the dark field has a substantially uneven cross-section.

The invention described in Item 33 is characterized in that the unevenness has a step which exceeds a depth of focus of an observation optical system for observing the first position recognizing section.

According to a thirty-fourth aspect of the present invention, a line in which a plurality of bright fields and a plurality of dark fields are alternately formed is formed by cutting a plurality of times by shifting the position of the cutting edge of the cutting tool. Is characterized by.

According to a thirty-fifth aspect of the present invention, in the fine lines, the ions in the focused ion beam processing apparatus are Ga.
When it is an ion, it has a width of about 1 to about 50 nm.

According to a thirty-sixth aspect of the present invention, the base material is placed on a stage of an electron beam drawing apparatus that draws with an electron beam, and the second position recognition of the base material is performed by a detection means. It is characterized in that a part is detected to obtain position coordinates, and based on the acquired position coordinates, the substrate is three-dimensionally drawn with an electron beam.

According to a thirty-seventh aspect of the present invention, a coating material is applied to the surface of the base material to form a coating layer before writing on the base material with an electron beam, and the electron beam is applied to the coating layer. Is performed.

Further, in the invention as set forth in claim 38, a step of developing the base material on which electron beam drawing is carried out and performing an etching treatment on the base material, and a mold of the base material by electroforming treatment It is characterized by including a process of creating.

Further, the invention according to claim 39 has a step of forming a molding base material by injection molding, using the mold having a shape corresponding to the second position recognizing part. It has a feature.

Further, the invention according to claim 40 is the step of developing the substrate on which electron beam drawing has been carried out, and subjecting the substrate to an etching treatment; and the step of forming the specific surface formed on one surface of the substrate. The step of cutting off the peripheral surface portion formed around the curved surface portion having the above-mentioned shape and forming a die of only the portion corresponding to the curved surface portion of the base material by electroforming is included.

Further, in the invention described in Item 41, a protective member is attached to the second position recognizing portion before the application of the coating material, and the protective member is removed after the application of the coating material. It is characterized by that.

The invention described in Item 42 is characterized in that it comprises a step of forming a molding substrate by injection molding using the mold.

The invention described in claim 43 is characterized in that the base material is formed of resin.

The invention described in Item 44 is characterized in that the base member is formed of n-type silicon.

The invention according to claim 45 is characterized in that the cutting tool is shaped while being cut with a diamond tool.

The 46th aspect of the present invention is characterized by including a step of molding an optical element by injection molding using the mold.

Further, in the invention according to claim 47, a curved surface portion formed on at least one surface, a peripheral surface portion formed around the curved surface portion, and the curved surface portion formed on the peripheral surface portion are the same. Corresponding to a base material including a first position recognizing part having a center of and a second position recognizing part formed at least three points around the curved surface part with the first position recognizing part as a reference. A method of manufacturing a base material, comprising forming a molding base material that is injection-molded using a mold, and manufacturing a final formed base material on the basis of the molding base material. Attaching a protective member, spin-coating a coating material on the curved surface portion of the molding base material, and baking the molding base material coated with the coating material, and then removing the protection member, An electron beam is applied to the curved surface portion of the molding base material. The base material is placed on a stage of an electron beam drawing apparatus that performs drawing, and the detection unit detects the second position recognition unit of the molding base material to acquire position coordinates, and the position coordinates Beam drawing process,
It is characterized by including.

The invention according to claim 48 is a substrate having a curved surface portion formed on at least one surface and a peripheral surface portion formed around the curved surface portion, wherein the peripheral surface portion A substantially concentric first position recognizing portion having the same center as the curved surface portion, and at least three second positions formed around the curved surface portion with the first position recognizing portion as a reference. The recognition unit is included.

[0060]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of a preferred embodiment of the present invention will be specifically described with reference to the drawings.

[First Embodiment] (Structure of Base Material) First, the feature of the present invention is that the curved surface part is processed by using a processing device for processing the curved surface part on the base material, and the base material is held. , A substantially concentric circular first mark having the same center as the curved surface portion in the same setup is processed in the peripheral portion of the curved surface portion of the base material, the first mark is recognized, and the first mark is formed in the vicinity of the first mark. After forming at least three second marks, resist coating and baking on the base material, the three-dimensional shape of the curved surface portion is measured with the second marks as a reference, and the drawing field is moved in electron beam drawing. On the occasion of "the second mark"
Is characterized by recognizing and positioning and performing electron beam drawing on the curved surface of the base material.

Prior to the explanation of such characteristics, first,
A schematic structure of the base material will be described with reference to FIGS. 1A and 1B are explanatory views showing a base material of the present embodiment, FIG. 1A is a cross-sectional view, and FIG. 1B is a plan view. In particular, FIG. The AA cross section is shown.

The base material 10 in the present embodiment shows a state after being processed by a lathe (ultra-precision lathe) which is an example of a processing apparatus and additionally processed by a focused ion beam processing apparatus. As shown in 1 (A) (B),
A preferable material for forming an optical element such as a lens,
For example, a curved surface portion 12 formed of n-type silicon or a resin member such as polyolefin and having a substantially semicircular cross section to form a curved surface, and a peripheral flat surface portion formed over a peripheral region of the curved surface portion 12. 14, a peripheral curved surface portion 16 formed so that a smooth curved surface is formed between the curved surface portion 12 and the peripheral flat surface portion 14, and a substantially concentric circular plane on the peripheral flat surface portion 14 (FIG. 1B). And has a substantially uneven cross section (see FIG.
(A)) which is a first position recognizing part and is a first mark 17, and a plurality of, for example, three second position recognizing parts are formed on the basis of the first mark 17. The mark 15 is included. In addition, the peripheral flat surface portion 14 and the peripheral curved surface portion 16 of the present example can configure a “peripheral surface portion”.

Here, more specifically, the base material 10 of the present embodiment is, as shown in FIG. 1A, a region extending from a top X1 (top of the base material 10) X2 of a curved surface such as a spherical surface. Is defined as a curved surface portion 12, while a peripheral area formed around the curved surface portion 12 which is a spherical surface extending from the peripheral edge X4 to X3 of the base material 10 is defined as a peripheral flat surface portion 14, and a peripheral flat surface between X2 and X3. The boundary area between the curved portion 14 and the curved portion 12 is surrounded by the curved surface portion 1
6 is set. The peripheral curved surface portion is configured such that in the resist coating step, the resist smoothly flows down from the curved surface portion 12 toward the peripheral flat surface portion 14 via the peripheral curved surface portion 16 to ensure the film thickness uniformity of the resist. This is because

The curved surface portion 12 includes an effective curved surface portion 12a from the center of the top portion to the required predetermined effective diameter r1. The curved surface portion 12 is not limited to the spherical surface as shown in the figure, and may be any other curved surface that is an aspherical surface.

By forming the peripheral flat portion 14, the resist solution can be efficiently scattered by the centrifugal force in the resist coating step, and the resist solution can flow down while maintaining the film thickness uniformity.

Further, as shown in FIG. 1B, the peripheral flat surface portion 14 has the base material 10 in each of the following steps.
It has a first mark 17 and a second mark 15 which serve as a reference for recognizing the position regarding. Here, the second mark 17 is, for example, for calculating a reference coordinate system for calculating an electron beam drawing position which is a height position on the curved surface portion 12 of the base material 10 in the electron beam drawing process. It is also a reference point for calculating the center O which is the center coordinate of the curved surface portion 12. Further, the first mark 17 is a reference mark for forming the second mark 15 with high accuracy, and will be described in detail later, but is formed in a substantially concentric circle shape by the same setup of the curved surface portion 12 and the same processing device. By
Since a reference line that is always equidistant from the central axis can be used, when the second mark 15 is formed, the first mark 17 is used as a reference, so that it can be used at any position in the circumferential direction. , A position equidistant from the center O can be calculated.

In the peripheral curved surface portion 16, as shown in FIGS. 1A and 1B, the first radius R1 of the curved surface portion 12 is approximately 1 of the second radius R2 of the curved surface forming the peripheral curved surface portion 16. It is preferable to configure so as to be formed by a double to approximately 10 times. Further, the boundary area position X3 between the peripheral flat surface portion 14 and the peripheral curved surface portion 16 where the inclination of the tangent line of the second radius R2 is substantially zero is separated from at least approximately twice the effective diameter r1 of the effective curved surface portion 12a. It is preferably formed at the position r2. This is because it is possible to promote the smooth flow-down of the resist by the peripheral curved surface portion 16 and obtain a uniform film thickness on the curved surface portion 12a within the effective diameter r1.

In this example, the peripheral curved surface portion 16
However, the present invention is not limited to this and may be formed by any curved surface or flat surface that is an aspherical surface.

The first mark 17 is formed in a substantially concentric plane shape having the same center as the center of the curved surface portion 12 with respect to the curved surface portion 12, and is formed in a substantially uneven cross section. For this reason, the line of the first mark 17 is shown in FIG.
, The dark field portion 17a-1 and the bright field portion 17b-
A plurality of lines consisting of 1 and 1 are formed, and the dark field portion 17a-2,
17a-3, and bright field portions 17b-2 and 17b-3. Further, the first mark 17 itself can function as a bank for preventing resist scattering due to the uneven shape as shown in the cross section of FIG.

On the other hand, the second mark 15 has a plurality of, for example, 3 marks.
In this example, as shown in FIG. 1 (A), each is formed into a substantially cross shape by fine lines engraved in a focused ion beam processing apparatus described later, and its cross section is substantially concave. Constitutes a concave portion of.

The second mark 15 has a substantially cross shape in plan view, and for example, as shown in FIG. 1B, the first mark 17 is formed substantially parallel to the first mark 17. Line 15
a and a second line 15b that is substantially orthogonal to the first line 15a
Consists of. Thereby, the second mark 1 for position recognition
5, the accuracy of recognition is improved, and an exposure apparatus for various steps described later,
The positioning accuracy in the EB (electron beam) drawing apparatus can be improved. The position of the second mark 15 is at least approximately 3 times the effective diameter r1 of the effective curved surface portion 12a.
It is preferable to form at a position r3 which is separated from the double.
Furthermore, in the above-mentioned example, the example in which the second mark 15 is formed as a concave concave portion by engraving has been described, but the present invention is not limited to this, and may be configured by a convex portion having a convex cross section. As a result, even if the surface of the peripheral flat surface portion 14 is covered with the resist, it is possible to recognize the position in the subsequent process by the convex mark.

Further, the second mark 15 forms a curved first line 15a parallel to the concentric circle of the first mark 15, but the present invention is not limited to this, and as shown by reference numeral 18b in FIG. It may be a cross of straight lines. This is because it can be easily recognized by human eyes. Furthermore, the shapes are not limited to the cross shapes that are orthogonal to each other, and may be cross shapes that intersect at least with each other, and further, various other shapes, such as a circle and a triangle. However, it is preferable that the shape has edges and corners because the point can be specified. On the other hand, if not, the shape of the second mark 15 itself is measured to determine the center position of the second mark 15. It is preferable.

In addition, the second mark 15 is not limited to the shape indicated by the reference numeral 18b shown in FIG. 3, but may be the shape in which only the first line is long like the reference numeral 18a. This allows
You can easily find the mark. Alternatively, as shown by reference numeral 18c, a thin film made of carbon deposited on the base material 10 may be deposited to form a cross. In this way, since the rectangular shape has an area, it can be more easily recognized. Note that the shape is not limited to a rectangular shape, and any other shape may be used as long as it has a shape having an area and a contour.

Further, FIG. 2B illustrates a case where the second mark 15 made of carbon is formed and only a dot is formed instead of a cross. As described above, when carbon is formed by vapor deposition, the boundary line and the points are clearly visible due to the edge effect of the boundary line, so that an arbitrary shape can be formed without forming the cross shape.

Furthermore, by forming the material of the base material 10 with, for example, a resin member, the base material 10 can be easily processed by injection molding, cutting, and the like, and can be easily supplied. That is, as a result of earnest studies by the present inventors, the solvent used in the resist for electron beam and the developer has a small change due to the solvent when the substrate 10 is formed of resin such as polyolefin. There was found.
Further, the substrate 10 is replaced with an impurity member of the first conductivity type, for example,
It is preferably formed of n-type silicon or the like. This is because it is easy to apply optical film thickness evaluation after resist application. It is also preferable in that it has anisotropy in the dry etching step described later. Note that the member is not limited to silicon as long as it can be anisotropically etched, and various metals and the like may be used.

Here, the base material 1 having the above-mentioned structure
0 acts roughly as follows. In addition, in the present embodiment, "a point where the first mark is formed by the same setup of the same machining device as the curved surface portion", "a point where the second mark is formed at least at three or more points with the first mark as a reference"", Etc., so that each of these items will be described in detail below.

Generally, as a condition for injection molding when manufacturing an optical element, it is necessary to set the positional deviation of the center line of the optical element within 1 micron so that the optical axis of the optical element does not deviate. . Therefore, when manufacturing one die, it is necessary to form concentric circles so that the center of rotation of the optical element can be known later.

In order to form the concentric circles, the concentric circles are machined and formed by the same machining apparatus as the machining apparatus that each machined and formed the curved surface portion 12 on the base material 10. Since the central axis of rotation does not move, the central axis of the curved surface portion and the central axis of the concentric circle are uniquely matched. In this way, the concentric circles of the first mark are processed and formed.

The processing apparatus used for this processing will be described later in detail, but is, for example, an SPD which is an ultra-precision lathe.
It is preferable to use a T processing device.

Specifically, the base material 10 having a three-dimensional shape
The cutting tool of the lathe for cutting the workpiece is relatively moved with respect to the surface to be processed of the base material 10 held by the rotation holding member that holds the base material 10 in rotation, so that the lathe is used to feed and cut. The base material 10 is cut while controlling the above.
After forming the curved surface portion 12 of the base material 10, the rotation holding member holds the base material 10 and the rotation center axis of the rotation of the base material does not move. The cutting tool cuts the substantially concentric first mark 17, which serves as a reference for recognizing the position of the base material 10.

As a result, the center axis of rotation does not shift on the same lathe. Therefore, by forming the first marks 17 concentrically, the center position is uniquely determined. That is, the center position can be known from the first mark 17. By forming the concentric circular first mark 17 itself, the coordinates of the center are calculated from the circle, and other coordinates are output with the center as a reference for electron beam drawing described later. It may be used for such height measurement.

On the other hand, the first mark 17 is used as a reference for the second mark.
By forming the mark 15 of, the accurate center position can be grasped also from the second mark 15.

Here, the base material 10 that three-dimensionally changes its shape
When a drawing pattern is drawn on the curved surface portion 12 of with an electron beam, three reference points are required as reference positions of the three-dimensional coordinate system, and these reference points have an accuracy on the order of several tens of μm. Therefore, it is necessary to form the reference mark used as the reference position with a fine line.

Therefore, in the machining by the lathe, the line width is limited depending on the shape of the cutting edge of the cutting tool for processing the processed surface of the base material 10. Therefore, with the blade of the cutting tool (in one finishing, ) It is not possible to write fine lines on the substrate.

Therefore, when the second mark 15 is formed with the concentric first mark 17 as a reference, for example, a focused ion beam device is used to form the second concentric mark 15.
Is preferably formed. As a result, the resolution can be further increased and fine processing can be performed. That is, the second mark 15 formed of a fine line has a structure sufficiently smaller than the first mark formed of a relatively thick line.

By the way, when the second mark 15 is formed, the concentric first mark 17 is formed in advance, and the first mark 17 is used as a reference, for example, substantially parallel to the first mark 17. Forming the first line 15a, and then forming the first line
By forming the second line 15b that is substantially orthogonal to the line 15a, it is possible to form the substantially cruciform second mark 15 (second position recognition portion).

When observing the second mark 15, the first mark 17 looks almost straight because it is observed at a magnification of 10,000 times or more, for example. Therefore, one line can be drawn by the focused ion beam processing device so as to be parallel to this straight line.

The second mark 15 corresponds to the first mark 1
It is preferable to form a plurality of, for example, three places at intervals on the outer circumference along the concentric circles 7. The plurality of second marks 15 do not need to be formed at equal intervals, and preferably have at least three points whose center positions can be calculated.

By forming the second marks 15 at three places, each second line 15b of each of the plurality of second marks 15 is formed.
Since the position of the central axis of the curved surface portion 12 is always located on the intersection of the points, the center of the curved surface portion 12 can be calculated by recognizing the second mark 15. Further, a reference position for calculating a three-dimensional reference coordinate system for measuring the three-dimensional shape of the curved surface portion 12 can be used. Note that the number of points is not limited to three, and in essence, the number of points at which the center position of the curved surface portion 12 can be calculated is sufficient.

As described above, by the second mark 15, positioning and position recognition (recognition of the position of the base material with respect to various manufacturing apparatuses, three-dimensional coordinates) can be performed by only looking at the second mark 15 in the subsequent process. It is possible to perform the recognition of the reference position for calculating the system). In particular, it is necessary to measure the height when performing electron beam drawing of a three-dimensional shape,
When measuring this height, in order for a person to visually recognize where the reference point of the coordinates related to the measurement data is, it is necessary to have recognizable points, which can be used as position recognition marks for recognizing these.

Although the second mark 15 may be provided inside the first mark 17, a protective member for protecting the second mark 15 when the resist is applied in the resist applying step described later. May be attached,
When the second mark 15 is on the outer side, the operability when performing the sticking is improved.

On the other hand, in the line of the first mark 17, the bright field portions 17b-1, 17b-2, 17b-3 and the dark field portion 1 are formed.
7a-1, 17a-2, 17a-3 are provided.
By pressing the cutting edge of the cutting tool against the rotating body, the line is drawn in a concentric circle.

Here, for example, if the first mark 17 is a single line, the recognition of the edge of the cut portion is poor.

Therefore, a plurality of bright and dark stripes are formed, and bright field portions 17b-1, 17b-2, 17b are formed.
-3 and the dark field parts 17a-1, 17a-2, 17a-3 are used. As a result, the machined surface looks neat and accurate position recognition can be performed.

The bright field parts 17b-1 and 17b-2.
17b-3 and dark field parts 17a-1, 17a-2, 17a
-3 can be formed by forming at least one inflection point or unevenness on the cutting edge of the cutting tool. In particular, when the cutting edge of the cutting tool is gradually worn, the shape of the cutting edge changes, but it is preferable to draw a line using this changed cutting edge. As a result, physical unevenness is uniquely formed on the cross section of the first mark 17, and in particular, by forming a plurality of uneven portions on the cutting edge of the cutting tool, a plurality of bright field portions 17b are alternately formed. -
1.17b-2.17b-3 and dark field 17a-1.
7a-2 and 17a-3 can be constructed by one-time cutting.

It is sufficient that the unevenness has a shape in which at least the surface changes, and the reflected light axis changes due to the change in the surface, so that a bright portion and a dark portion are formed. That is, when viewed with an optical microscope or the like, the light is bent to appear as a difference in brightness and darkness. Therefore, a configuration that changes the direction of reflected light, for example, a configuration that changes the direction of the surface may be used. Further, it is preferable to make a difference in unevenness that exceeds the depth of focus of the observation system.

As described above, the accuracy of the first mark 17 and the second mark 15 is increased in two steps to form the reference mark, and the high-precision mark having the reference accuracy is used.
Positioning can be performed in the subsequent process.

Here, in the present embodiment, the "base material and the first mark processing step" for processing the base material by the SPDT processing apparatus which is an ultra-precision lathe, the focused ion beam processing apparatus (FIB processing apparatus) "Processing of the second mark", "Resist coating process" by the resist coating device, "Electron beam writing process" by the electron beam writing device, "Developing process" by the developing device, etching device, etc., "Etching process", And "Mold making process",
Among them, the SPDT processing apparatus and the focused ion beam processing apparatus for processing the first mark and the second mark, which are characteristic of the present embodiment, are included. An example will be described below.

(Regarding SPDT processing apparatus) In the base material having the above-mentioned structure, the curved surface portion and the first mark are processed by, for example, a (super-precision) lathe, and the second mark is processed. For example, processing is performed by a focused ion beam processing device.

Here, an ultra-precision lathe for processing the base material 10, for example, SPDT (Single Point D)
A schematic configuration of a control system for iamond turning will be described with reference to FIGS. 4A and 4B.

As shown in FIG. 4 (A), the ultra-precision lathe 100 has a fixed portion 111 which is a rotation holding member for fixing the work 110 such as a base material and a work for processing the work 110. Diamond tool 112, which is the cutting edge of the cutting tool, a Z-axis slide table 120 that moves the fixing portion 111 in the Z-axis direction, and the diamond tool 112 while holding the diamond tool 112 in the X-axis direction (or in addition to the Y-axis direction). X-axis slide table 122 to move, Z
Axis slide table 120 and X axis slide table 1
And a surface plate 124 for movably holding 22. In addition, a rotation driving means (not shown) for rotationally driving either one or both of the fixed portion 111 and the diamond tool 112 is provided, and the control means 1 to be described later is provided.
Electrically connected to 38.

As shown in FIG. 4 (A), the ultra-precision lathe 100 has the Z-direction drive means 131 for controlling the drive of the Z-axis slide table 120 and the X-axis slide table 1.
An X-direction driving unit 132 and a Y-direction driving unit 133 for controlling the driving of the unit 22 in the X-axis direction (or in addition, the driving in the Y-axis direction), a feed amount control unit 134 for controlling the feed amount by these, and a disconnection unit. Cutting amount control means 13 for controlling the cutting amount
5, a temperature control means 136 for controlling the temperature, a storage means 137 for storing various control conditions, a control table or a processing program, and a control means 1 for controlling the respective parts.
And 38.

As shown in FIG. 4B, the diamond tool 112 has a diamond tip 1 which constitutes a main body portion.
13, a rake face 114 having an apex angle α formed at the tip portion thereof, a first flank 115, and a second flank forming a side face portion.
It is composed of the flank 116. The cutting edge included in the rake face 114 has a plurality of uneven portions 114a formed in advance or due to wear.

Ultra-precision lathe 10 having the above structure
At 0, it operates roughly as follows. That is, with respect to the work 110 that is the set base material (base material),
By the relative movement of the diamond tool 112,
The work 110 is processed. At this time, since the cutting edge of the diamond tool 112 has an R-bite structure, the point at which the cutting edge hits changes sequentially, and is resistant to wear.

In the present embodiment, when the base material 10 is processed using the above-described ultra-precision lathe, the feed amount and the cut amount are controlled while temperature control is performed. The curved surface will be cut.

At this time, the uneven portion 114a is abraded by abrasion or the like.
Can be formed. After that, the work 110 is fixed to the fixing portion 111.
The fixed portion 111 is rotated while being fixed to the curved surface portion 1
The first mark 17 having a concentric circle shape is cut around the circumference of 2 using the diamond tool 112. As a result, the first mark 17 having the same center as the curved surface portion 12 can be obtained.

The first mark 17 may be cut by using another diamond tool (not shown) in which the concavo-convex portion 114a is formed in advance. In this case, the curved surface portion 12 and the first mark 17 may be formed by using the other diamond tool.

By the way, when the first mark 17 is formed by using the diamond tool 112, the concavo-convex portion 11 is formed.
It can also be assumed that 4a cannot be formed deep due to wear. As a measure in that case, the position of the cutting edge may be shifted and formed by a plurality of cuts, and as a result, the first mark 17 having an uneven cross section may be formed.

The first mark 17 does not necessarily have to be formed by the diamond tool 112 which is a cutting tool. For example, if the curved portion 12 is formed while the center of rotation is generated by the rotation of the fixed portion 111 and a concentric circle can be formed with respect to the same center of rotation, the curved portion 12 may be processed by another device. . For example, the curved surface portion 12 may be formed by the diamond tool 112 in a state where the work 110 is fixed to the fixed portion 111, and the curved surface portion 12 may be formed by irradiating a laser beam or the like in the state of being fixed to the fixed portion 111 as well.

(Regarding Focused Ion Beam Processing Apparatus) (Description of Configuration) Next, a schematic configuration of a focused ion beam processing apparatus for forming the second mark will be described with reference to FIG.

Focused ion beam processing device (FIB: Fo)
The processed Ion Beam apparatus) is a processing of a substrate by a focused ion beam using a metal ion source such as Ga or an observation of a scanning image obtained by scanning the substrate with the focused ion beam (SIM: Scanning Ion Micros).
The ion beam generated from the ion source and accelerated is finely focused by an electrostatic condenser lens, objective lens, etc. to irradiate the substrate, and the irradiation point of the ion beam on the substrate Is scanned by a deflector, secondary electrons generated from the substrate by this scanning are detected, and a scanning image or the like is displayed based on the detection signal. An example of the configuration of the FIB is shown below in FIG.

The focused ion beam processing apparatus 200 is held in a high vacuum, and as shown in FIG. 5, a liquid metal ion source 201 serving as an ion source, an extraction electrode 202 for extracting ions, and an ion beam with a desired energy. An accelerating tube 203 having a plurality of stages for accelerating, a condenser lens 204 whose aperture can be changed by an aperture 205 which limits an ion beam, and an aperture 207 whose aperture can be variably adjusted to focus an ion beam and irradiate a sample with an objective lens 206. , Deflector 208, blanking / E × B
An E × B mass analyzer 209 equipped with a limiting aperture, an emitter alignment 210, an alignment set stigmeter 211, an alignment set 212, an alignment set stigmeter 213, a base material to be processed are placed, and the position and inclination of the base material are set. Freely adjustable stage 214, detector 21 for detecting position recognition marks, etc.
5, a laser interferometer 217 including a laser supply source 216 and an optical system, a stage driving unit 220 that drives the stage 214, and a control circuit 2 that controls each of these units.
30, an operation input unit 261 for performing an operation input, an image recognition unit 260 for observing and recognizing a base material and a scan image, a power supply (not shown), and the like.

Each of the apertures 205 and 207 has an opening whose ion beam diameter and the like can be changed by, for example, limiting the passage of the ion beam. is doing. Note that the aperture may be formed in N stages.

The detector 215 is for detecting, for example, secondary electrons generated based on the irradiation of the base material 10 with the ion beam.

The stage driving means 220 moves the stage to the X position.
X-direction drive mechanism 221, for driving in the Y-direction, Y-direction drive mechanism for driving in the Y-direction, Z-direction drive mechanism for driving in the Z-direction, and θ-direction drive mechanism for driving in the θ-direction. And are included.

The control circuit 230 includes an ion source control circuit 231 for controlling the ion source 201, an accelerating tube control circuit 232 for controlling the accelerating tube 203, and a first focusing control circuit 233 for controlling focusing by the condenser lens 204. A second focusing control circuit 234 for controlling the focusing by the objective lens 206, a deflection control circuit 235 for controlling the deflector of the deflector 208, a stage control circuit 236 for controlling the stage driving means 220, and a substrate. Controlling a detector control circuit 237 for controlling signal processing from the detector 21 for detecting secondary ion generated, a laser interferometer control circuit 238 for controlling the laser interferometer 217, and an E × B mass analyzer 209. Ion selection control circuit 23 for selecting ions with
9, emitter alignment 210, alignment set stigmator 211, alignment set 212,
First to fourth alignment control circuits 240 and 241 respectively controlling the alignment set stigmators 213
242 and 243, a storage unit 250 that stores various control tables and programs, a display processing unit 251 that displays various display images, and a control unit 252 such as a CPU that controls these. ing.

The storage section 250 is realized as an area of a storage device such as a semiconductor memory or a disk device,
A combination of image data and position data is also stored. For example, position data composed of position coordinates of a cross section and cross-sectional image data in which pixels forming each cross-sectional image data are stored in a scanning order can be combined and stored as a pair of data. The storage unit 250 is provided with a plurality of areas for storing this data, and the above-mentioned data corresponding to each cross section formed at a specific location of the base material 10 can be stored, for example, arranged in the order of position data. .

The display processing unit 251 displays, for example, an image or the like on the basis of each image data and position data accumulated in the storage unit 250 in order to display a specific portion, and the image recognition unit 260.
Process to display. The display processing unit 251
From the data stored in the storage unit 250, any X, Y, Z
The pixel data of the coordinates may be read out and a stereoscopic image viewed from a desired viewpoint may be displayed on the image recognition unit 260. There are various possible display methods,
For example, it is preferable to extract the contour from the adjacent pixel data, determine the front-back relation of the contour, and display the hidden portion with a broken line or the like. Further, with respect to the image data, image processing such as contour extraction due to a change in luminance is performed, and a hole formed by an ion beam,
By recognizing the size and position of a characteristic portion of the surface of the base material such as a line, whether or not the stage 214 arranges the base material 10 at a desired position, and by the ion beam, a hole having a desired size, It may be possible to determine whether a line has been formed on the substrate 10.

The control section 252 is, for example, the detector control circuit 2
A detection signal from the detector 215 is received via 37 to form image data and an operation input unit 261.
, Or various conditions are set in each unit based on the image data or the like. Further, according to the user's instruction input from the operation input unit 261 or the like, the stage 21
4 and each part for ion beam irradiation can be controlled.

Further, the control section 252 uses the detector control circuit 237 to convert the detector 21 into a digital value.
Receive all detection signals from 5. The detection signal changes according to the scanning position of the ion beam, that is, the deflection direction of the ion beam. Therefore, the surface shape and material of the base material 10 at each scanning position of the ion beam can be detected by synchronizing the deflection direction and the detection signal. The control unit 252 can reconstruct them according to the scanning position and display the image data of the surface of the base material 10 on the image recognition unit 260.

(Explanation of Operation) In the focused ion beam apparatus 200 having the above-described structure, first, the curved surface portion 12 and the first mark 17 are formed on one surface on the stage 214 provided in the focused ion beam apparatus 200. Base material 1
The focused ion beam apparatus 200 is set up by setting 0 and setting the surroundings in a vacuum state so that the substrate 10 can be scanned with the ion beam.

Next, an area of the substrate 10 is scanned with the ion beam. At this time, the ions from the ion source 201 are generated at an extraction voltage of 5 to 10 kV, and the acceleration tube 203
Will be accelerated. The accelerated ion beam is focused by the condenser lens 204 and the objective lens 206,
The substrate 10 on the stage 214 is reached.

When an alloy ion source such as Au—Si—Be is used, only the necessary ions are made to go straight by the E × B mass analyzer 209, and the orbits of the unnecessary ions are bent to make them necessary. Ions can be separately selected.

Further, when handling ions having isotopes such as Si, adjustment control is performed so that the crossover point of the ion beam by the condenser lens 204 is located at the center of the E × B mass analyzer 209. It is preferable. Thereby, the isotopes can be effectively used without being separated. In this way, the ions can be focused on the substrate by the objective lens 206 and scanned, for example in a raster fashion.

Secondary electrons or secondary ions emitted from the surface of the base material 10 are detected by scanning, image processing is performed by the display processing unit 251 based on the detection result, and SIM showing the surface shape of the region is obtained. The image is displayed on the image recognition unit 260. For example, a SIM image is displayed each time the stage 214 is moved, and the stage 214 is displayed so that a specific portion can be displayed.
Align the.

The user uses, for example, the operation input unit 261 or the like to set the processing area, the processing time, and the ion beam current value as the processing condition settings for the SIM image displaying the specific portion. Good to specify. For example,
A SIM image of the surface of the base material is acquired, a processing region is set for a specific location, and the processing time of the processing region and the ion beam diameter and current value of the ion beam used for the processing are designated. In addition, you may observe the state of a base material using other observation optical systems not shown.

Here, in the present embodiment, the first recognition mark on the base material is recognized by the image recognition section 260 based on the detection signal from the detector 215.

Then, the first line 15a parallel to the line of the first mark 17 is formed by the ion beam. On this occasion,
By the relative movement of the stage 214 and the ion beam,
It is preferable that the first line 15a is formed so as to draw a part of an arc or be linear.

At this time, the focused ion beam processing apparatus 200
Scans the processing area. Material of base material, type of ion beam (difference in ion beam current value) and energy,
Since the amount of sputtering is determined by the dose amount and the like, the processing region is dug to a substantially constant depth by one scanning. Further, in response to scanning, all detection signals of secondary electrons and secondary ions are stored in the storage unit 250, image data at a specific location is acquired, and an image at an arbitrary position is obtained according to a user's instruction. be able to.

Next, a second line 15b that is substantially orthogonal to the first line 15a is formed by the ion beam.

A plurality of second marks 15 can be formed by forming a plurality of these, for example, three places in the direction along the circumference of the concentric circle of the first mark 17.

The procedure for forming the second mark 15 at three locations is not limited to the above, but may be changed in advance.
The first line 15a for three points may be formed by rotating the stage 214 intermittently, and then the second line 15b for each point may be formed.

Furthermore, when these control procedures and the like are stored in advance in the storage unit 250 as a control program and the second marks 15 are formed from the operation input unit 261 at three places, for example, “3 In the case of forming five places, by inputting “5”, the first mark 17 is automatically detected and the point where the second mark 15 should be formed is automatically calculated, and the execution start button It is preferable that the second mark 15 is automatically formed by pressing the button or the like.

As described above, the focused ion beam apparatus is used to perform observation with the observation optical system of the focused ion beam apparatus, the secondary ion image, etc., and the first mark is recognized, and the stage position of the focused ion beam apparatus is recognized. To know the coordinates. The focused ion beam is scanned at the coordinate position to form the second mark.

Here, the line width (focusing of the beam) is, for example, preferably about 1 nm to about 50 nm. However, it is limited to the case of implanting Ga ions. More preferably, it is about 20 nm. This is because the displacement of the central axis of the optical element must be within 1 μm, and the position can be determined by a diameter that is sufficiently smaller than this 1 μm.

As described above, the "concentric circular first mark 17" is recognized, and in the vicinity thereof, the second mark 15 for positioning reference composed of the lines perpendicular to each other is provided. Depending on the processing device, for example, 0.001-0.0
It can be formed by engraving with fine lines of 50 [μm].

The focused ion beam processing apparatus is not limited to such an example, but processing by an ion beam and surface observation are simultaneously performed to sequentially obtain images of a plane parallel to the surface of the base material, and to obtain a three-dimensional image. It may have a configuration of accumulating as image data and obtaining an arbitrary cross section by image conversion.

(Regarding Overall Structure of Coating Material Coating Device) Next, regarding the schematic structure of the entire resist coating device for coating a coating material such as a resist on the above-described base material on which the first and second marks are formed. , Will be described with reference to FIG. FIG. 6 is a functional block diagram showing a schematic configuration of the entire resist coating apparatus used in the resist coating step.

The resist coating apparatus 301 of this embodiment
As shown in FIG. 6, a (coating material coating device) is a spin coater that is a holding member that holds a base material 10 that is a base material to be coated on which a coating material, for example, a resist is coated, while rotating around a rotation axis O. Coating material coating means for coating the resist by continuously flowing down the chuck 320 and the resist (L shown in FIG. 6) as the coating material from above in the position of the rotation center axis O with respect to the base material 10. 334, a viscosity control unit 337 that controls the viscosity of the resist, a coating amount control unit 336 that adjusts and controls the amount of the resist applied by the coating material applying unit 334, and when the resist is continuously flowed down. The coating material supply time control means 335 for controlling the resist supply time and the rotation drive means for rotating the spin coater chuck 320 in the θ direction about the rotation center axis O. A moving means 330, the drive means 33
Spin coater chuck 320 when rotating at 0
Rotation speed control means 332 for controlling the rotation speed of the resist, and a correlation table showing the correlation between a predetermined resist amount and the rotation speed so that the film thickness of the applied resist becomes substantially uniform, and further surrounding environment conditions. For example, the storage unit 338 stores various control condition information such as condition information including temperature control conditions, and the control unit 340 that controls these.

Naturally, the resist coating apparatus 301 controls the ambient environment conditions, such as temperature conditions, which are one of the control conditions for resist coating, during the resist coating so that the film thickness becomes substantially uniform. In addition, a temperature control means (not shown) linked to the above-mentioned control means 340 is provided. The temperature control condition is, for example, 2
The setting is preferably controlled at 2 to 24 ° C., and at the time of baking at 100 to 200 ° C.

The spin coater chuck 320 is composed of the base material 10.
In order to retain the rotation of the base material 10, by defining the peripheral edge portion of the base material 10, the first direction restricting portion that restricts the movement in the first direction F in which the centrifugal force at the time of rotation is generated, or the base material 10. Recessed side wall portion 322 which is a chuck portion for chucking
And the bottom wall portion 3 of the recess for holding the bottom surface of the base material 10 by its own weight.
24, and has a substantially concave cross section.

The driving means 330 includes an X-axis direction driving means and a Y-axis direction driving means for driving the spin coater chuck 320 so that the spin coater chuck 320 is moved in the X-axis and Y-axis directions on the XY plane constituting the resist coating surface. Means (not shown) and spin coater chuck 32 on which the substrate 10 is placed
After transporting 0 from the predetermined mounting position to the resist coating position, the spin coater chuck 3 at the resist coating position
Each direction (θ direction ·
Each adjusting mechanism (not shown) for Z direction, X direction, Y direction),
It is configured to include.

The control means 340 controls the viscosity on the basis of the number of revolutions by the driving means 330 and the coating amount of the resist. Further, based on the supply time controlled by the coating material supply time control means 335, the coating material application means 33 is provided.
The rotation speed control means 332 controls the first and second rotation speeds in accordance with the presence or absence of the supply of the coating material by No. 4. further,
After the resist is continuously supplied by the coating material coating unit 334, the spin coater chuck 320 is rotated by the driving unit 330.

According to the resist coating apparatus 301 having the above-mentioned structure, the operation is roughly as follows. That is, in the resist coating apparatus 301 of this embodiment,
As will be described in detail later in the item “Processing procedure”, it has a processing procedure of “continuously supplying resist into press pin and performing main spinning”.

Before applying the resist, a protective member such as a protective tape is attached to each of the plurality of second marks 15 of the base material 10 in advance.

When resist coating is to be performed, first, during the first rotation called “press pin”, the spin coater chuck 320 is rotated by the driving means 330 while the coating material is coated. Means 334 is substrate 1
The resist L is continuously flown to 0. On this occasion,
Various control information is programmed in the storage means 338 so as to perform drive control at a predetermined timing, and based on the control information, the control means 340 causes the coating material supply time control means 335 to perform a certain period during press pinning. To supply the resist from the coating material applying means 334, and also to the rotation speed control means 332 (supply a control signal) so that the driving means 330 rotates at a predetermined first rotation speed (for example, 200 rpm). Further, the coating amount control means 336, so as to control the coating amount and viscosity of the resist,
The viscosity control unit 337 is controlled.

Next, in the second rotation called “main spin”, the resist solution continuously flowing down by the coating material coating means 334 is stopped, and then the spin coater chuck 320 is driven by the driving means 330. To rotate. At this time, the control unit 340 instructs the coating material supply time control unit 335 to control not to supply the resist for a certain period, and the second rotation speed becomes higher than the first rotation speed.
The rotation speed control means 332 is instructed to rotate the drive means 330 at the rotation speed (for example, 700 rpm).

When the resist coating is completed, the protective tape is peeled off, and the process moves to the next step with the second mark 15 visible.

(Regarding Electron Beam Drawing Device) (Structure Description) Next, a schematic structure of the entire electron beam drawing device will be described with reference to FIG. FIG. 7 is an explanatory diagram showing the overall configuration of the electron beam writing apparatus of this example.

As shown in FIG. 1, the electron beam drawing apparatus 401 forms an electron beam probe of high resolution with a large current and scans the substrate 10 to be drawn at high speed. An electron gun 412, which is an electron beam generating means for forming a line probe to generate an electron beam to irradiate the target with the beam, a slit 414 for passing the electron beam from the electron gun 412, and a slit 41.
4, an electron lens 416 for controlling the focal position of the electron beam passing through the substrate 2 with respect to the base material 2, and an aperture for arranging the electron beam on the path through which the electron beam is emitted to have a desired electron beam shape. 418, a deflector 420 that controls the scanning position and the like on the substrate 10 that is a target by deflecting the electron beam, and a correction coil 422 that corrects the deflection. It should be noted that these units are arranged in the lens barrel 410 and are maintained in a vacuum state when the electron beam is emitted.

Further, the electron beam drawing apparatus 411 is an XY which is a mounting table for mounting the substrate 2 to be drawn.
Z stage 430, a loader 440 that is a transfer unit that transfers the base material 10 to a mounting position on the XYZ stage 430, and a measurement for measuring a reference point on the surface of the base material 10 on the XYZ stage 430. Measuring device 48 as means
0, a stage driving unit 450 which is a driving unit for driving the XYZ stage 430, a loader driving device 460 for driving the loader, the inside of the lens barrel 410 and the XYZ.
A vacuum exhaust device 470 that exhausts the inside of the housing 411 including the stage 430 to be a vacuum, an observation system 491 that observes the base material 10, and a control circuit 492 that is a control unit that controls these. It is configured to include.

The electron lens 416 includes coils 417a, which are installed at a plurality of locations in the height direction at intervals.
A plurality of electronic lenses are generated by the respective current values of 417b and 417c, so that the electronic lenses are respectively controlled and the focal position of the electron beam is controlled.

The measuring device 480 includes a first laser length measuring device 482 for measuring the base material 10 by irradiating the base material 10 with a laser, and a laser emitted by the first laser length measuring device 482. Light (first irradiation light) reflects the base material 10 and receives the reflected light. The first light receiving unit 484 and the first laser length measuring device 482 perform irradiation from different irradiation angles. A laser length measuring device 486, and a second light receiving portion 488 for receiving the reflected light by reflecting the laser light (second irradiation light) emitted by the second laser length measuring device 486 from the base material 10. , Is included.

The stage driving means 450 includes an X-direction driving mechanism 452 for driving the XYZ stage 430 in the X-direction,
It includes a Y-direction drive mechanism 454 that drives the XYZ stage 430 in the Y-direction, a Z-direction drive mechanism 456 that drives the XYZ stage 430 in the Z-direction, and a θ-direction drive mechanism 458 that drives the XYZ stage 430 in the θ-direction. It is composed of. As a result, the XYZ stage 430 can be operated three-dimensionally and alignment can be performed.

Although the control circuit 492 is not shown,
An electron gun power supply unit for supplying power to the electron gun 412, an electron gun control unit for adjusting and controlling current, voltage and the like in the electron gun power supply unit, and an electronic lens 416 (each of a plurality of electronic lenses) are provided. A lens power source for operating the lens power source and a lens controller for adjusting and controlling each current corresponding to each electron lens in the lens power source are included.

Further, the control circuit 492 controls the correction coil 422, a coil control section, a shaping deflecting section for deflecting the shaping direction by the deflector 420, and a sub-scanning direction for deflecting the deflector 420. Sub-deflection unit for deflector 420
, A main deflection unit for performing deflection in the main scanning direction, an electric field control circuit that is electric field control means for controlling the electric field of the electron beam,
A pattern generation circuit for generating a drawing pattern or the like on the base material 2, various laser control systems, a stage control circuit for controlling the stage driving means 450, a loader control circuit for controlling the loader driving device 460, and measurement information. A measurement information input unit for inputting, a memory that is a storage unit for storing the input information and a plurality of other information, a program memory storing a control program for performing various controls, and a control including each unit The system includes a system and a control unit formed by, for example, a CPU that controls the respective units.

(Explanation of Operation) In the electron beam drawing apparatus 401 having the above-described structure, when the substrate 10 carried by the loader 440 is placed on the XYZ stage 430, the vacuum pumping apparatus 470 causes the lens barrel 410. After exhausting air, dust, and the like in the housing 411, an electron beam is emitted from the electron gun 412.

The electron beam emitted from the electron gun 412 is deflected by the deflector 420 via the electron lens 416, and the deflected electron beam B (hereinafter, the deflection-controlled electron beam after passing through the electron lens 416) is deflected. May be referred to as "electron beam B" only)
Drawing is performed by irradiating the surface of the base material 10 on the XYZ stage 430, for example, the drawing position on the curved surface portion (curved surface) 12.

At this time, the measuring device 480 measures the drawing position (at least the height position of the drawing position) on the base material 10 or the position of the reference point as described later, and the control circuit 492 makes the measurement. Based on the result, by adjusting and controlling each current value flowing in the coils 417a, 417b, 417c of the electron lens 416, the position of the focal depth of the electron beam B, that is, the focal position is controlled, and the focal position is the drawing position. The movement is controlled so that

Alternatively, based on the measurement result, the control circuit 4
92 controls the stage driving means 450 to move the XYZ stage 430 so that the focal position of the electron beam B becomes the drawing position.

In this example, either one of the electron beam control and the XYZ stage 430 control may be performed, or both may be used.

Then, the first laser length-measuring device 482 of the measuring device 480 is used to move the substrate 1 from the direction crossing the electron beam.
The first light intensity distribution is detected by irradiating 0 with the first light beam S1 and receiving the first light beam S1 that passes through the base material 10.

At this time, the first light beam S1 is emitted from the substrate 1
Since it is reflected at the bottom of 0, the (height) position on the flat portion of the base material 10 is measured and calculated based on the first intensity distribution. However, in this case, the (height) position on the curved surface portion 12 of the base material 10 cannot be measured.

Therefore, in this example, a second laser length measuring device 486 is further provided. That is, the second laser beam length measuring device 486 irradiates the base material 2 with the second light beam S2 from a direction substantially orthogonal to the electron beam different from the first light beam S1 and transmits the base material 10. Second
The second light intensity distribution is detected by receiving the second light beam S2 by the second light receiving unit 488, and the position is measured and calculated based on the second light intensity distribution.

Then, with the height position of the base material as the drawing position, the focal position of the electron beam is adjusted and the drawing is performed.

(Outline of Principle of Drawing Position Calculation) Next, an outline of the principle of drawing in the electron beam drawing apparatus 401 will be described.

In the base material 10, the base material 10 is XYZ beforehand.
Before being placed on the stage 430, a plurality of, for example, three reference marks P00 of the second marks 15 on the base material 10,
P01 and P02 are determined and this position is measured (first measurement). By this, the first in the three-dimensional coordinate system
The reference coordinate system of is calculated. Here, the height position in the first reference coordinate system is Ho (x, y) (first height position)
And Thereby, the thickness distribution of the base material 2 can be calculated.

On the other hand, after placing the base material 10 on the XYZ stage 430, the same processing is performed. That is, the base material 1
A plurality of reference points P10, P11, P12 on 0
Is determined and this position is measured (second measurement). Thereby, the second reference coordinate system in the three-dimensional coordinate system is calculated.

Furthermore, these reference points P00, P01,
A coordinate conversion matrix or the like for converting the first reference coordinate system into the second reference coordinate system is calculated by P02, P10, P11, and P12, and the second reference coordinate system is used by using this coordinate conversion matrix. The height position Hp (x, y) (second height position) corresponding to Ho (x, y) at is calculated, and this position is set as the optimum focus position, that is, the drawing position, and the focus position of the electron beam is It will be the position to be combined.

The above-mentioned second measurement can be carried out by using the measuring device 480 which is the first measuring means of the electron beam drawing device 401.

Then, the first measurement needs to be performed in advance at another place by using another measuring device (shape measuring instrument). Such a base material 2 is attached to the XYZ stage 430.
As a measuring device for measuring the reference point in advance before mounting on the measuring device, a measuring device (second measuring means) having the same structure as the above-described measuring device 480 can be adopted. In this case, the measurement result from the measuring device is input, for example, in the measurement information input unit, or data is transferred via a network (not shown) connected to the control circuit 492 and stored in the memory or the like. .

As described above, the drawing position is calculated, the focal position of the electron beam is controlled, and the drawing is performed.

Specifically, the depth of focus FZ of the electron beam
The focus position of (beam waist BW) is adjusted and controlled to the drawing position within one field (m = 1) of the unit space in the three-dimensional reference coordinate system. (This control is, as mentioned above,
Either one or both of the adjustment of the current value by the electronic lens 416 and the drive control of the XYZ stage 430 are performed. ) Then, for example, by sequentially scanning within one field, drawing within one field is performed. Further, if there is an area that is not drawn in one field, the area is also moved in the Z direction while controlling the focus position, and drawing processing by the same scanning is performed.

Next, after drawing in one field is performed, another field, for example, m = 2 field, m =
In the third field, the drawing process is performed in real time while the measurement and the drawing position are calculated as described above. In this way, when all the drawing is completed for the drawing area to be drawn, the drawing process on the surface of the base material 2 is completed.

In this way, the position recognition is performed using the second mark as the reference point, and the drawing process is performed.

(Regarding Processing Procedure) Next, when the base material having the above-mentioned structure is manufactured by using the above-mentioned various apparatuses, a processing step which is a prerequisite thereof and a second processing by the focused ion beam processing apparatus are performed. Regarding the mark forming process, further, the processing procedure when applying the above-mentioned resist,
This will be described in detail with reference to FIGS. 8 and 9
In the description, some of the reference numerals are omitted.

(Processing Step by SPDT) First, as shown in FIG. 8, when a base material is cut, an ultra-precision lathe, for example, SPDT (Single Point Diam) is used.
The base material (base material) is set on the fixed part which is the chuck of the on-durning processing device (step, hereinafter referred to as “S”).
101 ").

Next, a curved surface and an aspherical surface are processed by performing diamond cutting on the base material.

Subsequently, the concentric first mark is processed (S102). Here, the first mark is formed on the base material in the same processing setup as the curved surface portion, and is formed on the outer peripheral portion of the base material in a substantially concentric shape. At this point, no deviation occurs between the center of the rotation axis (the apex of the three-dimensional shape and the optical axis of the subsequent optical element) and the first mark.

Furthermore, since the cutting edge of the diamond tool has a worn or pre-formed concavo-convex portion (or a shape having one or more inflection points), it is possible to make an optical microscope by cutting once. And the like, the first mark is formed by unevenness in which dark field portions and bright field portions are alternately formed. The first mark has geometrical features (different surface orientations, unevenness exceeding the depth of focus of the observation system, etc.) to obtain a regular edge image corresponding to the dark field portion and the bright field portion. Will have. Note that the first mark may be formed by cutting a plurality of times by shifting the position of the cutting edge.

Then, the base material is removed from the fixed portion, which is the chuck of the SPDT processing device (S103), and the cutting process is completed. Further, the substrate is washed and then dried.

(Second Mark Forming Step by Focused Ion Beam Processing Device) Next, the base material on which the curved surface portion and the concentric first mark are formed by cutting is subjected to FIB.
(Focused ion beam) It sets on the stage of a processing apparatus (S104). Further, the image recognition means (image recognition unit) of the FIB processing apparatus detects the concentric first mark (S105).

Subsequently, second marks are formed at least at three or more locations by FIB processing, with the formation position of the concentric first marks as a reference (S106). In the subsequent process, the second mark enables highly accurate positioning.

The second mark is the focused ion beam (FI).
In B), the first mark is recognized and the points, lines, and marks are dug. The line width can be reduced to 0.001 to 0.050 [μm], and more preferably to about 20 [nm].

Then, the base material on which the second mark is formed is removed from the stage of the FIB processing apparatus (S10).
7). This completes the second mark processing step.

Thus, as shown in FIG. 10A, the base material 500 having the curved surface portion 516, the first mark 517 and the second mark 515 is obtained.

Next, as shown in FIG. 8, a protective tape is attached to the second mark formed on the base material (S1).
08).

(Coating Material Coating Step) Next, the base material is set on a spin coater (S109), and press pins (rotary coating at the first rotation speed) are performed while the resist (coating material) is allowed to flow down (S110). Next, a main spin (rotation at a second rotation speed higher than the first rotation speed) is performed (S11).
1).

More specifically, the spin coater chuck is aligned at a predetermined resist dropping position by the driving means, and the rotation speed control means drives the spin coater chuck at a predetermined first rotation speed (for example, 200 rpm). The press pin is started by rotating in the θ direction by means.

Then, while the substrate is rotated, a predetermined amount of resist liquid L is continuously flowed down and supplied around the rotation center by the coating material coating means. At this time, various control conditions such as a resist coating amount and an environmental condition corresponding to the rotation speed of the spin coater chuck so that the film thickness becomes uniform are controlled by the coating amount control means, the rotation speed control means, and the control means. .

In this press pin, the resist was continuously flown down to the top of the curved surface of the base material, and was flowed down to the top as the base material was rotated at a predetermined first rotation speed. The resist is applied while flowing down smoothly from the apex toward the peripheral curved surface portion and the peripheral flat surface portion around the curved surface portion while maintaining a substantially uniform film thickness.

During this period, when the resist is continuously supplied and rotated at a predetermined rotation speed, the resist L spreads from the curved surface portion to the peripheral flat surface portion via the peripheral curved surface portion.

Next, after a lapse of a predetermined period, the coating material supply time control means gives an instruction to the coating material coating means to stop the resist supply, stops the resist supply, and sets the rotation speed higher than the first rotation speed. Second rotation speed (eg 700 rpm)
Up to, the rotation speed is increased by using the rotation speed control means to perform the main spin. In this main spin, the rotation speed is, for example, 700 r
It is preferred to rotate as pm. In this main spin, the continuous supply of the resist is stopped, and the substrate to which the resist is applied is rotated at a second rotation speed higher than the first rotation speed.

Subsequently, the base material coated with the resist is baked (heated) at a predetermined temperature (S).
112). Then, the base material coated with the resist is removed from the spin coater (S113), and the resist coating process is completed. In this step, since the resist coating is performed with the protective tape attached to the second mark, the shape of the second mark is maintained.

In this way, as shown in FIG. 10B, the resist L on which the protective seal 520 is attached is attached.
A base material 500 coated with is obtained.

Then, as shown in FIG. 8, after the application of these resists is completed, the protective tape protecting the second mark is peeled off (S114).

After spin coating, it is preferable to measure the film thickness of the resist film and evaluate the resist film.

(Shape Measuring Step) Next, the substrate is set on the shape measuring device (second measuring device) (S115), and the second mark is detected by the image recognizing means of the shape measuring device ( (S116) The reference position for three-dimensional shape measurement is recognized.

That is, the three reference points P0n = (xn, yn, zn) by the second mark of the substrate, each measurement of n = 1 to 3, and the height Ho (x, y) of each part of the substrate The measurement is performed with a shape measuring instrument.

Further, using the detected second mark as a reference, the shape data of the substrate to be coated is measured and recorded in the storage means (S117). Subsequently, the base material is removed from the shape measuring instrument (S118), and the shape measuring step is completed.

(Electron Beam Drawing Step) Next, as shown in FIG. 9, the base material measured by the shape measuring instrument is set on the stage of the electron beam (EB) drawing apparatus (S1).
19).

Then, the second mark is detected by the SEM, which is an observation system mounted on the electron beam writing apparatus, and the position coordinates of the second mark on the XYZ stage of the electron beam writing apparatus are acquired (S120). At this time, the shape data measured by the shape measuring instrument is written from the storage means of the shape measuring instrument to the storage means in the electron beam drawing apparatus. This writing may be either automatic or manual input.

Then, based on the measured shape data of the substrate already measured, the XYZ stage of the electron beam drawing device is driven so as to match the drawing field of the electron beam drawing device to give a desired dose amount ( S121), electron beam drawing of a predetermined shape is performed on the base material. Nochi, Figure 10
Drawing with the electron beam B is performed on the base material 500 shown in FIG.

In the present embodiment, the measurement result measured by the shape measuring instrument is input using the measurement information input unit of the electron beam drawing apparatus. The shape measuring instrument is connected to the network in one clean room or chamber, and the measurement result measured by the shape measuring instrument is uniquely stored in the storage means in the electron beam drawing apparatus to form a "system". If so, the above-mentioned input work becomes unnecessary. This “system” includes a shape measuring device (second measuring device) for measuring the base material in advance before the setting, and a measuring device (first measuring device) for measuring the base material after the setting. For convenience, it may be defined as an electron beam drawing apparatus including two measuring devices. Furthermore, a configuration in which these measuring devices are combined to be capable of performing both measurements (for example, in the transport path between when the substrate is chucked and then transported to the stage, the measurement position before the setting (first position) and The measuring device moves between the measuring position (second position) after setting, and the measuring stage for measuring before setting is set to the first position and the measuring stage is set to the second position.
The measurement stage and the stage may be prepared in advance, and one of the stages may be positioned at the measurement position of the drawing position.

More specifically, the drawing process is performed by the three reference points P1n (Xn, Yn, Z) of the second mark on the base material.
The measurement of n) is performed using the measuring device provided in the drawing area of the electron beam drawing device.

Then, in the electron beam drawing apparatus, the three reference points P0n (xn, yn, zn) measured in advance as described above are used.
Information and information on the height Ho (x, y) of each part (first coordinate system), and the three reference points P1n (Xn, Y) measured above.
The optimum focus position Hp (x, y) of the beam in the electron beam drawing apparatus is calculated based on the information (second coordinate system) of (n, Zn).

By the way, this is strictly for one field (for example, a unit space of 0.5 × 0.5 × 0.05 mm) (m = 1). By the way, drawing is performed by scanning the beam in this one field. Next, the XYZ stage is moved to one specific field divided into m, and processing is performed to perform drawing at a position within the depth of focus f. In this way, drawing is performed for other fields.

Subsequently, the drawn substrate is removed from the stage of the electron beam drawing apparatus (S122), and the electron beam drawing process for the substrate is completed.

(Development and Etching Step) Next, as shown in FIG. 9, resist development is performed while positioning the base material and the like to obtain a resist shape (S123). Where S
You may perform the process of evaluating a resist shape by EM observation, a film thickness measuring device, or the like.

Subsequently, the base material is dry-etched to transfer the resist shape onto the base material (S124). Thereby, for example, a diffraction grating structure 502 as shown in FIG. 10D is obtained.

(Mold forming step) Then, as shown in FIG. 10 (E), in order to prepare a mold 530 for the surface-treated base material 500, as shown in FIG. 9, mold electroforming is performed. After performing the pretreatment, the electroforming treatment or the like is performed to electroform the base material (S125).

Next, the base material is removed and the mold is removed (S1).
26). Then, with the second mark transferred to electroforming as a reference, the center position of the base material shape part transferred to electroforming, and
Electroforming is shaped and surface-treated to obtain a die shape so that the center position of the outer shape of the die after shaping coincides (S12).
7).

Thus, as shown in FIG. 10F, the shape 533 corresponding to the diffraction grating, the shape 531 corresponding to the first mark, and the shape 532 corresponding to the second mark.
A mold 530 having

Thereafter, although not shown, the mold surface treatment,
The mold can be evaluated, and after the evaluation, a molding substrate can be obtained by injection molding using the mold. Then, the molding base material is evaluated.

As described above, according to this embodiment, the second
Marks are used for position recognition in the shape measurement of the substrate by the shape measuring device (measuring device), position recognition for recognizing the position coordinates in the three-dimensional electron beam drawing device, and position recognition at the time of mold making. Is used, but such a second
When forming the mark, in the process of processing the base material (base material) to form the curved surface portion on the base material, the marks are continuously (in the same setup) formed concentrically.

Normally, when forming a curved surface portion, the base material is rotated by the rotation holding member while the cutting tool is brought into contact with the cutting tool, but the concentric first mark is also processed in the same manner. be able to. That is, since the center of rotation when the substrate rotates is fixed,
The center axis of the cut curved surface portion and the center axis of the concentric first mark will coincide with each other. This makes the first
A line that is equidistant from the center of the curved surface portion can be formed on the line of the mark. As a result, the concentric axis shift is 1
It can be within (μm). Since the second mark is formed on the basis of the first mark, the center position of the base material (curved surface portion) can be recognized by recognizing the second mark without recognizing the first mark. It is possible to recognize a reference (position on the base material) for grasping.

At this time, by forming the second marks in a number such that the center point of the curved surface portion can be calculated, for example, at least three or more locations, the center position of the curved surface portion can be recognized by recognizing the second mark. It will be easier and more reliable.

Further, since the first mark is formed by the concavo-convex line portion consisting of the bright field and the dark field, when observing the concave portion or the convex portion of the first mark with the optical microscope, the concave or convex portion Since the edge image arranged as the boundary line between the dark field and the bright field is obtained within the range, the first mark can be easily recognized. Further, when forming the line portion composed of the bright field and the dark field, it can be easily formed by utilizing the unevenness of the cutting edge of the cutting tool. In particular, by paying attention to the fact that as the cutting tool is used, the uneven shape (having one or more inflection points) is uniquely formed due to the wear of the cutting edge, a blade with special unevenness is prepared. Without doing so, a line consisting of a bright field and a dark field can be formed.

Also, with such a blade shape, it is possible to form a plurality of lines with one cut.

The line consisting of the bright field and the dark field preferably has a substantially uneven cross section, and at least the direction of the plane may be changed. At this time, by providing a difference (step) in unevenness that exceeds the depth of focus of the observation system, when observing the bottom wall of the concave portion with the optical microscope, an ordered edge image corresponding to the boundary between the bright field and the dark field is obtained with the optical microscope. This makes it easier to recognize the first mark.

Further, the second mark should have a substantially cross shape composed of a first line substantially parallel to the line of the first mark and a second line substantially orthogonal to the first line. Than the second
Even though the mark is a fine line, it can be easily recognized.

Further, these lines can be formed as fine lines by a focused ion beam processing apparatus, and the fine lines are preferably formed with a width of about 1 to about 50 nm, for example. By engraving and imparting such fine lines, the concentric axis misalignment falls within, for example, approximately 1 [μm], and since the fine lines are approximately 0.001 to approximately 0.050 [μm], the electron in the subsequent process The position accuracy / resolution of the mark recognition information of the beam drawing device is improved.

By forming the first line or the second line long, the second mark can be formed more easily.

Further, the second mark may be formed by forming a thin film in which carbon is vapor-deposited on the base material and processing this thin film. In this case, in addition to the edge effect of the line by carbon, by forming the side in the deposited carbon film, there is a contour on the outer periphery of the point, the area is large, and the shape is more easily recognized by humans. Become.

At this time, it is more preferable that the FIB processing device is used to deposit the carbon at an interval of 0.001 to 0.050 [μm] so that the gaps are orthogonal to each other. This eliminates the need for a protective tape or the like for preventing the resist from spreading at the intended place where the second mark is applied when the resist is applied.

Further, even when a conductive film for preventing charge-up at the time of drawing with an electron beam, for example, an Au film is pushed over the resist, it is possible to perform engraving processing so that Au and the base material, such as Si. And the contrast of the SEM observation image can be obtained.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIG. Note that, in the following, description of substantially the same configuration as that of the first embodiment will be omitted, and only different portions will be described.

In the above-described first embodiment, the first and second marks are transferred to electroforming in the process of manufacturing a mold or the like for manufacturing an optical lens such as an optical element by injection molding. However, without transferring the first and second marks to electroforming, the shape of only the curved surface portion of the base material is transferred to electroforming, and the shape of the curved surface portion of the base material (and the blaze on the curved surface portion) is transferred. shape)
You may use the method of comprising the metal mold | die for obtaining.

That is, the same processing as S101 to S124 is performed. Specifically, the base material is machined with a cutting tool by the above-described ultra-precision lathe,
As shown in (A), a base material 600 having a curved surface portion 616.
And the first mark 617 is formed in the same setup. Then, the second mark 615 is processed by the FIB processing device.
To form. Then, as shown in FIG. 11B, the second
A protective tape 620 is attached to the mark 615 and resist coating is performed, and after completion, the protective tape 620 is peeled off and electron beam drawing is performed as shown in FIG. 11C.

Then, development processing and etching processing are performed to obtain a diffraction grating structure 602 shown in FIG.

The process up to this point is the same as in the first embodiment, but here, as indicated by the dotted line K, the peripheral surface portion is cut off to form only the curved surface portion.

Then, in order to prepare the mold 630 for the base material 600 having only the curved surface portion provided with the diffraction grating structure 602, as shown in FIG. An electroforming process or the like is performed, and as illustrated in FIG. 11F, a process of separating the base material 600 and the mold 630 is performed.

Mold 6 separated from the surface-treated base material
The surface treatment is performed on 30, and the die 630 is evaluated. After the evaluation, a molding substrate is created using the mold 630.

As described above, according to the present embodiment, it is possible to form only the curved surface portion when manufacturing the mold for injection molding the above-mentioned optical element. In the case of such a configuration, the cutting may be performed at any step after the electron beam drawing. In any of these steps, the peripheral flat surface portion and the peripheral curved surface portion are cut. Accordingly, it is possible to configure the base material having only the curved surface portion obtained by cutting the peripheral curved surface portion and the peripheral flat surface portion.

Further, in the above-mentioned example, the mold in which the first and second marks are not formed is used, but the mold in which only the second mark is not formed may be used.

[Third Embodiment] Next, a third embodiment of the present invention will be described with reference to FIG. 12A and 12B are explanatory views showing the third embodiment according to the present invention.

In the above-described embodiment, the second mark is formed as the second position recognizing section. However, as in the base material 730 shown in FIGS. The concave portion or the convex portion and the position recognition mark may be respectively configured. Specifically, the base material 730 has an effective curved surface portion 732.
a curved surface portion 732 including a, a peripheral flat surface portion 734, a peripheral curved surface portion 736, a first position recognition portion 737, and a peripheral flat surface portion 734.
A convex portion or a concave portion 738 which is a resist outflow direction control member provided on the upper side, and a position recognition mark 73 which is provided on the peripheral flat surface portion 734 outside the convex portion or the concave portion 738.
5 is included. Thereby, the direction in which the resist is applied and spread can be controlled by the convex portion or the concave portion 738 as shown by the arrow J, and by forming the position recognition mark 735 on the outside thereof, the position recognition mark 735 is surrounded. The resist does not spread. This makes it easier to recognize the position in the subsequent process. The position recognition mark is preferably formed on the same plane as the peripheral plane portion.

Although the apparatus and method according to the present invention have been described according to some specific embodiments thereof,
Those skilled in the art can make various modifications to the embodiments described in the text of the present invention without departing from the spirit and scope of the present invention.

For example, in the step before resist coating,
The base material itself may be made by injection molding. In this case, first and second marks are created on the base material in advance,
The first mark and the second mark may be formed by injection molding. It is preferable when the substrate is mass-produced.

[0241] Further, the method and the constitution in which the curved surface portion of the base material is formed by one cutting tool and then the first mark is formed are made. However, by using two or more cutting tools, one cutting tool is used. A method and configuration may be used in which the position recognition mark is formed by the other cutting tool while forming the curved surface portion.

Further, the above embodiment includes various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. That is,
It goes without saying that the embodiments include the embodiments described above or a combination of any of them with any of the modifications. In this case, even if it is not particularly described in the present embodiment, as for the action and effect apparent from each configuration disclosed in each of the embodiments and the modifications, it is of course possible to obtain the action and effect in this example as well. . Further, it may be a configuration in which some of the constituent elements are deleted from all the constituent elements shown in the embodiment.

The above description discloses only one example of the embodiment of the present invention, and can be appropriately modified and / or changed within a predetermined range, but each embodiment is illustrated. It is a thing, not a limitation.

[0244]

As described above, according to the present invention, when the base material is formed, the base material is rotated by the rotation holding member and the cutting tool is brought into contact to perform cutting. By processing the first position recognizing unit by the same setup as the process of forming the specific shape on the top, the rotation center of the base material and the rotation center of the first position recognizing unit are aligned. Accordingly, by using the first position recognition unit as a reference for various position recognition in various manufacturing processes, the position recognition accuracy in each manufacturing process is improved and the processing accuracy is improved. Further, it is possible to reduce the positional deviation of the finally produced base material.

Further, by forming the second position recognizing unit with the first position recognizing unit as a reference, by recognizing the second position recognizing unit without recognizing the first position recognizing unit. It is possible to recognize the reference for grasping the center position of the base material. The second position recognizing unit is, for example, position recognizing in shape measurement of a base material that changes in shape three-dimensionally, position recognizing for recognizing position coordinates in a three-dimensional electron beam drawing apparatus, and position recognizing at the time of mold making It is used to do etc. At this time, by forming a number of second position recognizing units capable of calculating the center point of the base material, the calculation of the center position of the base material becomes easier and more reliable.

Further, the second position recognizing section has a substantially cross shape having a first line substantially parallel to the line of the first position recognizing section and a second line substantially orthogonal to the first line. By configuring, it becomes possible to easily recognize.

Further, since the first position recognizing section is formed by the line portion consisting of the bright field and the dark field, an edge image arranged as a boundary line can be obtained at the time of observation. Easy to recognize. Furthermore, when forming a line portion having a bright field and a dark field, it can be easily formed by utilizing the unevenness due to the wear of the cutting edge of the cutting tool.

Further, the second position recognizing section can be formed by forming a thin film of carbon vapor-deposited on the base material and processing this thin film. The second position recognizing section has an area corresponding to the contour of the outer circumference due to the edge effect of the line. , The shape is easier for humans to recognize.

[Brief description of drawings]

1A and 1B are explanatory views showing a structure of a base material according to an embodiment of the present invention, wherein FIG. 1A is a sectional view and FIG. 1B is a plan view.

2 (A) and 2 (B) are explanatory views showing details of a base material in an embodiment of the present invention, and FIG.
FIG. 3B is a plan view showing an example of the position recognition unit of FIG.

FIG. 3 is an explanatory diagram showing a specific example of a second position recognition unit of the base material according to the embodiment of the present invention.

4 (A) is a functional block diagram showing an example of the configuration of an ultra-precision lathe used for processing a base material, and FIG. 4 (B) shows the same in the ultra-precision lathe of FIG. It is a perspective view which shows an example of the cutting edge of a diamond tool.

FIG. 5 is an explanatory diagram showing an example of a configuration of a focused ion beam processing apparatus used for processing a base material.

FIG. 6 is an explanatory diagram showing an example of a configuration of a coating agent coating device used for processing a base material.

FIG. 7 is an explanatory diagram showing an example of the configuration of an electron beam drawing apparatus.

FIG. 8 is a flow chart showing an example of a processing procedure of a method for producing a base material of the present invention.

FIG. 9 is a flowchart showing an example of a processing procedure of a method for manufacturing a base material of the present invention.

10A to 10F are explanatory diagrams for explaining an example of the overall processing procedure when a molding die is formed using a base material.

11A to 11F are explanatory views for explaining an example of the overall processing procedure when a molding die is formed using a base material.

12A and 12B are explanatory views showing an example of another embodiment of the base material.

[Explanation of symbols]

10 Base material 12 curved surface 14 Peripheral plane 15 Second mark (second position recognition part) 16 Surrounding curved surface 17 First mark (first position recognition unit) 100 Super-precision lathe (SPDT processing device) 200 Focused ion beam processing equipment 301 Coating material coating device 401 Electron beam drawing device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Akanebe ▲ Yuichi             2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Stock Association             In-house (72) Inventor Osamu Masuda             2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Stock Association             In-house F term (reference) 2H049 AA03 AA18 AA33 AA37 AA43                       AA48 AA63 AA64 AA68 AA69                 4E066 BA13 CB08

Claims (48)

[Claims] 1. An optical element microfabrication method for performing microfabrication for an optical element, which comprises rotatingly holding a base material and moving a cutting means relative to a surface to be processed of the base material. A first step of forming the base material into a predetermined shape; a second step of forming a position recognition unit serving as a position recognition reference on the base material in a state where the rotation axis of the base material does not move; and an electron beam While mounting the base material on the stage of the electron beam drawing apparatus that performs drawing by the above, the position recognizing unit of the base material is detected by the detecting means to acquire the position coordinates, and based on the acquired position coordinates. And a third step of performing three-dimensional drawing with an electron beam on the base material, the optical element microfabrication method. 2. The optical element microfabrication method according to claim 1, wherein the position recognizing unit includes a first position recognizing unit formed in a substantially concentric shape with respect to the rotation center axis. 3. The optical element microfabrication method according to claim 2, wherein the position recognizing unit includes a second position recognizing unit formed with the first position recognizing unit as a reference. 4. The optical element fine processing method according to claim 3, wherein the substrate is three-dimensionally drawn with an electron beam based on the position coordinates of the second position recognizing unit. . 5. The first position recognition part is formed in a concentric circle shape substantially concentric with the rotation center of the base material, and the second step is a step of recognizing the first position recognition part, The method according to claim 3, further comprising: a step of forming a first line substantially parallel to the first position recognizing unit; and a step of forming a second line substantially orthogonal to the first line. The optical element fine processing method as described. 6. A step of forming a substantially cross shape formed by the first line and the second line in a number capable of calculating the center position of the base material around the periphery of the first position recognition unit. The optical element microfabrication method according to claim 5, further comprising: 7. The optical element microfabrication method according to claim 6, wherein at least three or more cross shapes are formed around the first position recognition portion. 8. The method according to claim 3, wherein in the second step, the second position recognizing unit is formed by digging a fine line using a focused ion beam processing apparatus. Optical element microfabrication method. 9. The optical element microfabrication method according to claim 3, wherein the second position recognition part is formed by a line thinner than the first position recognition part. 10. The optical element microfabrication method according to claim 2, wherein the first position recognizing portion is formed in a shape having different surface directions. 11. The first position recognition unit is formed by a line consisting of a bright field and a dark field.
The optical element microfabrication method according to. 12. At least one on the cutting edge of the cutting tool.
The optical element microfabrication method according to claim 2, wherein the first position recognition part is processed into a shape having at least one inflection point. 13. The method according to claim 11, wherein the line consisting of the bright field and the dark field is formed by utilizing the unevenness of the cutting edge of the cutting tool. 14. The unevenness is formed by abrasion of a cutting edge of a cutting tool.
4. The optical element fine processing method according to item 3. 15. The optical element fine processing method according to claim 11, wherein the line formed by the bright field and the dark field has a substantially uneven cross-section. 16. The optical element microfabrication method according to claim 13, wherein the unevenness has a step that exceeds a depth of focus of an observation optical system for observing the first position recognition unit. 17. The line according to claim 11, wherein a line in which a plurality of bright fields and a plurality of dark fields are alternately formed is formed by cutting a plurality of times by shifting the position of the cutting edge of the cutting tool. Optical element microfabrication method. 18. A method of manufacturing a base material, which comprises manufacturing a base material by processing the base material with a processing device, wherein a cutting tool of a processing device for processing the base material holds the base material in rotation. A first step of forming the base material in a specific shape by moving the base material held by the rotation holding member relative to the surface to be processed, and after forming the specific shape in the base material A first reference serving as a position recognition reference on the base material in a state in which a rotation center axis of the base material held by the rotation holding member rotates
And a second step of forming the position recognizing part, and the method for producing a base material. 19. The method according to claim 1, further comprising a third step of forming a second position recognizing portion serving as a reference for positioning the base material, with the position of the first position recognizing portion as a reference. 18. The method for producing a base material according to item 18. 20. The first position recognition part is formed in a concentric shape substantially concentric with the rotation center of the base material, and the third step recognizes the first position recognition part, The step of forming a first line substantially parallel to the first position recognizing unit, and the step of forming a second line substantially orthogonal to the first line are included. A method for producing the described base material. 21. A substantially cross shape formed by the first line and the second line is formed around the first position recognizing section,
21. The method of manufacturing a base material according to claim 20, further comprising forming a number of central positions of the base material that can be calculated. 22. The method of manufacturing a base material according to claim 21, wherein at least three or more cross shapes are formed around the first position recognition portion. 23. In the third step, the second line is formed by digging a fine wire using a focused ion beam processing apparatus.
The method for manufacturing a base material according to claim 19 or 20, wherein the position recognition part is formed. 24. The method of manufacturing a base material according to claim 19, wherein the second position recognition part is formed by a line thinner than the first position recognition part. 25. The third step includes: a step of forming a thin film of carbon deposited on the base material; and a step of processing the thin film to form the second position recognizing part. The method for producing a base material according to claim 19, wherein: 26. The method of manufacturing a base material according to claim 18, wherein the first position recognizing portion is formed in a shape capable of obtaining a regular edge image. 27. The method of manufacturing a base material according to claim 18, wherein the first position recognition portion is formed in a shape having different surface directions. 28. The first position recognition section is formed by a line composed of a bright field and a dark field.
8. The method for producing a substrate according to item 8. 29. At least one is provided on the cutting edge of the cutting tool.
The method for producing a base material according to claim 18, wherein the first position recognition part is processed into a shape having at least one inflection point. 30. The method for producing a base material according to claim 28, wherein the line consisting of the bright field and the dark field is formed by utilizing the unevenness of the cutting edge of the cutting tool. 31. The unevenness is formed by abrasion of a cutting edge of a cutting tool.
0. The manufacturing method of the base material of 0. 32. The method for producing a base material according to claim 28, wherein the line formed by the bright field and the dark field has a substantially uneven cross section. 33. The method for manufacturing a base material according to claim 30, wherein the unevenness has a step that exceeds a depth of focus of an observation optical system for observing the first position recognition unit. 34. The line in which a plurality of bright fields and a plurality of dark fields are alternately formed is formed by cutting a plurality of times by shifting the position of the cutting edge of the cutting tool. Of manufacturing the base material of. 35. The base material according to claim 23, wherein the fine line has a width of about 1 to about 50 nm when the ions of the focused ion beam processing apparatus are Ga ions. Method. 36. The substrate is placed on a stage of an electron beam drawing apparatus that draws with an electron beam, and the detection means detects the second position recognizing unit of the substrate to obtain position coordinates. Then, based on the acquired position coordinates, three-dimensional electron beam drawing is performed on the base material.
The method for manufacturing a base material according to any one of claims 9 to 35. 37. A coating material is applied to the surface of the base material to form a coating layer before drawing on the base material with an electron beam, and the electron beam is applied to the coating layer. Item 36. A method for producing a base material according to Item 36. 38. A method, comprising: developing the substrate on which electron beam drawing has been performed, etching the substrate, and forming a mold of the substrate by electroforming. 38. The method for manufacturing a base material according to claim 37, which is characterized in that. 39. The method according to claim 37, further comprising the step of forming a molding base material by injection molding using the mold having a shape corresponding to the second position recognizing section.
The method for producing a base material according to 1. 40. A step of developing the substrate on which an electron beam is drawn and performing an etching process on the substrate, and a step of forming a curved surface having a specific shape on one surface of the substrate. The method for producing a base material according to claim 37, further comprising: a step of cutting off the formed peripheral surface portion and creating a mold of only a portion corresponding to the curved surface portion of the base material by electroforming. . 41. A protective member is attached to the second position recognizing unit before applying the coating material, and after applying the coating material,
The protection member is removed, and the protection member is removed.
7. The method for producing a base material according to 7. 42. The method for producing a base material according to claim 38, further comprising the step of forming a molding base material by injection molding using the mold. 43. The method for manufacturing a base material according to claim 18, wherein the base material is formed of a resin. 44. The method of manufacturing a base material according to claim 18, wherein the base material is made of n-type silicon. 45. The method for producing a base material according to claim 18, wherein the cutting tool is shaped while being cut with a diamond tool. 46. The method for producing a base material according to claim 42, further comprising a step of molding an optical element by injection molding using the mold. 47. A curved surface portion formed on at least one surface, and a peripheral surface portion formed around the curved surface portion,
A first position recognition part formed on the peripheral surface part and having the same center as that of the curved surface part, and a second position recognition part formed around the curved surface part based on the first position recognition part.
And a position recognizing unit, and a molding base material that is injection-molded using a mold corresponding to the base material, and a final formation base material is manufactured based on the molding base material. A step of applying a protective member to the second position recognizing unit and spin-applying a coating material on a curved surface portion of the molding base material; and the molding base coated with the coating material. After baking the material, a step of removing the protective member, and placing the base material on a stage of an electron beam drawing apparatus that draws an electron beam on the curved surface part of the molding base material, A step of detecting the second position recognizing unit of the molded base material, acquiring position coordinates, and performing electron beam drawing based on the position coordinates. 48. A base material having a curved surface portion formed on at least one surface and a peripheral surface portion formed around the curved surface portion, the center being the same as that of the curved surface portion formed on the peripheral surface portion. A substantially concentric first position recognizing part, and at least three second position recognizing parts formed around the curved surface part with the first position recognizing part as a reference. Base material to be.