Method for manufacturing pretreated substrate, molding apparatus, molding method, and method for manufacturing article

Abstract

To provide a method for manufacturing a pretreated substrate, suitable for a substrate used in a molding technique such as imprinting, in which unevenness at the end of a step portion in the outer periphery of the substrate is reduced.SOLUTION: A method for manufacturing a pretreated substrate includes the steps for measuring the position of a step located in the peripheral region of a substrate, the outermost periphery of which is lower than the inside, supplying a protective film forming material to the inside of the measured step of the substrate, and forming a protective film such that the protective film forming material is not placed at the end of the step of the substrate, and etching the end of the step of the substrate.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a pretreated substrate used in a molding technique such as imprinting, a molding apparatus, a molding method, and a manufacturing method of an article. [Background technology]

[0002] Imprint technology, which uses an imprint mold to mold an imprint material on a substrate, is known as a molding technology for manufacturing semiconductor devices, etc. In the imprint technology, an imprint mold (mold) is brought into contact with the imprint material on a substrate, the imprint material is cured, and the mold is peeled off from the cured imprint material, thereby forming a concave-convex pattern made of the imprint material on the substrate.

[0003] The imprint mold has a region on its contact surface that comes into contact with the imprint material, where a concave-convex pattern is provided. Furthermore, the region that comes into contact with the imprint material is often configured to be formed on the top surface of a mesa portion that protrudes from one surface of the mold.

[0004] Patent document 1 describes that when imprinting a partial area (partial field) at the edge of a substrate in an imprinting apparatus, a step is formed on the outer periphery of the substrate to prevent contact between the mold and the portion of the substrate outside the imprint area.

[0005] Patent document 2 discloses an imprinting method in which the ejection position of the imprinting material is adjusted based on the measurement results of the step position in order to reduce contamination of the mold when the imprinting material ejected outside the step position comes into contact with the mold. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2018-74160 A [Patent Document 2] JP 2018-73989 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the processed substrate used in conventional imprinting, there are cases where unevenness exists in the stepped portion due to a problem with the processing accuracy of the stepped portion on the outer periphery of the substrate.

[0008] These irregularities cause variations in the way the imprint material spreads, particularly in the thin portions of the imprint material between the mold and the substrate, which can result in defects in the formed pattern.

[0009] Therefore, an object of the present invention is to provide a method for manufacturing a pretreated substrate that reduces unevenness at the edge of a step portion on the outer periphery of the substrate, suitable for substrates used in molding techniques such as imprinting. [Means for solving the problem]

[0010] In order to achieve the above object, a method for producing a pretreated substrate according to one aspect of the present invention includes the steps of: measuring the position of a step disposed in an outer peripheral region of the substrate, the step causing the outermost periphery to be lower than the inner side; applying a protective film forming material to an inner upper surface of the measured step of the substrate, and forming a protective film such that the protective film forming material is not disposed on an end of the step of the substrate; Etching an edge of a step in the substrate; has.

[0011] Further objects or other aspects of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings. Effect of the Invention

[0012] According to the present invention, there is provided a method for manufacturing a pretreated substrate that reduces unevenness in the steps at the outer periphery of the substrate. By performing imprinting using the substrate, it is possible to reduce pattern defects due to unevenness in the steps of the substrate. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 illustrates an imprint apparatus according to a first embodiment. [Diagram 2] 4 is an image diagram of projections and recesses in a step portion on the outer periphery of a substrate according to the first embodiment. FIG. [Diagram 3] 6A to 6C are diagrams illustrating defective filling of a stepped portion on the outer periphery of a substrate in the first embodiment. [Figure 4] 5 is an etching flowchart for reducing unevenness in a step portion according to the first embodiment. [Diagram 5] 13 is an explanatory diagram of the ejection position of a protective film in the second embodiment. FIG. [Figure 6] 1A to 1C are diagrams for explaining a method for manufacturing an article. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0015] First Embodiment FIG. 1 is an explanatory diagram of a molding apparatus (imprint apparatus) having a protective film supplying function for manufacturing a preprocessed substrate according to the first embodiment.

[0016] Here, the surface on which the substrate 3 is placed is defined as the XY plane, and the direction perpendicular to that is defined as the Z direction, and the various axes are determined as shown in Fig. 1. The imprint apparatus 1 includes a light source 2, the substrate 3, a substrate holding unit 4 that holds the substrate 3, a protective film forming material supply unit 5 that supplies a protective film forming material 10, a substrate transport device 7 that transports the substrate 3, and a mold 15 and a mold holding unit 21 that holds the mold 3.

[0017] The light source 2 is an illumination means for irradiating light 12 (ultraviolet rays) that cures the protective film forming material 10 during the formation of the protective film. The light 12 is irradiated through an optical element 11 that adjusts the light emitted from the light source 2 to an appropriate light for irradiating the imprint material.

[0018] The substrate holding unit 4 is a holding means that holds the substrate 3 by vacuum or electrostatic adsorption and is movable within the XY plane. The substrate holding unit 4 is driven along a stage base 8 of the imprint apparatus 1. The imprint apparatus 1 is equipped with a substrate measurement unit 6 that can measure the surface of the substrate 3. The substrate measurement unit 6 is a distance measuring device that can measure the distance in the Z-axis direction between the surface of the substrate 3 and the substrate measurement unit 6. The substrate holding unit 4 moves along the XY plane, allowing the substrate measurement unit 6 to measure each position (entire surface) of the surface of the substrate 3. The substrate measurement unit 6 may measure the surface of the substrate 3 by moving along the XY plane.

[0019] The material supply unit 5 is a supply means for supplying the protective film forming material 10 onto the substrate 3. The protective film forming material 10 is a curable composition (sometimes called an uncured resin) that is cured when curing energy is applied. The curing energy may be electromagnetic waves, heat, or the like. The electromagnetic waves may be, for example, infrared light, visible light, ultraviolet light, or other light having a wavelength selected from the range of 10 nm or more and 1 mm or less.

[0020] The curable composition is a composition that is cured by irradiation with light or by heating. Among them, the photocurable composition that is cured by light contains at least a polymerizable compound and a photopolymerization initiator, and may contain a non-polymerizable compound or a solvent as necessary. The non-polymerizable compound is at least one selected from the group consisting of a sensitizer, a hydrogen donor, an internal mold release agent, a surfactant, an antioxidant, a polymer component, and the like.

[0021] The protective film forming material 10 may be applied onto the substrate in the form of droplets, or in the form of islands or a film formed by a plurality of droplets connected together, by the material supply unit 5. The viscosity of the imprint material (viscosity at 25° C.) is, for example, 1 mPa s or more and 100 mPa s or less.

[0022] The substrate 3 is made of silicon, glass, ceramics, metal, semiconductor, resin, etc., and may have a member made of a material different from that of the substrate formed on its surface as required. Specific examples of the substrate include silicon wafers, compound semiconductor wafers, and quartz glass.

[0023] The substrate transport device 7 is a transport means for transporting the substrate 3 into the substrate holding unit 4 and transporting the substrate 3 out of the imprint apparatus 1.

[0024] 2 is an image diagram of the edge of a substrate. In imprinting a partial field (partial region) at the edge of a substrate, in order to prevent contact between the mold and the portion of the substrate outside the imprint region, the height of the substrate outside the imprint region is reduced by etching or the like, and if the surface between the higher and lower surfaces of the step is defined as the side, and the end of the higher surface adjacent to the side is defined as the end of the step, unevenness may occur at the end of the step 13.

[0025] 3 is an image diagram showing imprinting material 14 filling the gap between a mold 15 and a substrate 3 during imprinting in a partial field at the edge of a substrate. In areas with unevenness at the edge of a step, the amount of imprinting material that fills the mold pattern in the recesses may be insufficient, and defective filling 16 may occur.

[0026] FIG. 4 is a flowchart of a method for manufacturing a substrate for imprinting in which unevenness at stepped portions of the substrate is reduced and shape change at etching processed boundaries is small.

[0027] First, the substrate measuring unit detects the positions of the steps by measuring the substrate height at multiple points on the substrate periphery from the substrate periphery toward the substrate center or from the substrate center toward the substrate periphery. Next, the coordinates of the positions of the steps at multiple points on the substrate are approximated, and the approximate values ​​are used as the coordinates of the positions of the steps around the entire substrate periphery.

[0028] Next, the amount of unevenness at the step position is measured using an AFM or similar device, and the etching time required to reduce the unevenness is determined.

[0029] Next, based on the coordinates of the step position, a protective film is formed on the substrate from the step position on the inside. In this method, the imprint material supply unit 7 of the imprint device 1 discharges a protective film forming material as a protective film on the inside from the step position, and after the droplets spread on the substrate, the protective film is hardened by exposure light to form the protective film. The thickness of the protective film is determined from the ratio of the etching rates of the substrate (silicon) and the protective film forming material, and the etching time.

[0030] It is preferable to have a database of the spreading radius of the droplets of the protective film forming material relative to the elapsed time on the substrate and the time required for the gaps between the droplets to be filled. The ejection position is adjusted so that the droplets are located inside the unevenness of the step to be etched by the time it takes for the gaps between the droplets of the protective film forming material to be filled.

[0031] Then, based on the position of the step, an etching process is performed on the area including the position to reduce the unevenness at the step, and the protective film is then peeled off. This method makes it possible to reduce the unevenness at the step while minimizing the change in shape of other parts.

[0032] <Second embodiment> An embodiment for reducing the amount of unevenness at the position of the above-mentioned step will be described below.

[0033] The above-mentioned substrate measurement unit 6 measures the substrate height at multiple points on the periphery of the substrate 3 from the substrate periphery 17 toward the substrate center or from the substrate center toward the substrate periphery 17 to detect step positions 18. Next, the coordinates of the step positions 18 at multiple points on the substrate are approximated, and the approximate coordinates of the step positions around the entire substrate periphery are set as (Xi, Yi).

[0034] The amount of unevenness at the step position is measured using an AFM or other device, and the amount of etching (A) required to reduce the unevenness is determined. Next, based on the ratio (B) of the etching rate of the substrate under the etching conditions to the etching rate of the protective film material, the film thickness (C) of the protective film material is set such that (C) ≧ (A) / (B).

[0035] The density (D) of the protective film forming material on the substrate required to achieve the film thickness (C) of the protective film forming material is calculated by dividing the film thickness (C) of the protective film forming material by the volume per droplet of the protective film forming material ejected from the material supply unit, and the arrangement of the droplets of the protective film forming material on the substrate is determined based on the density of the protective film forming material.

[0036] The time it takes for the gaps between droplets of the protective film forming material to be filled (filling time) and the radius E of the droplet at that time are obtained from a database obtained in advance.

[0037] Next, the ejection position of the protective film forming material will be described with reference to FIG.

[0038] The center of the substrate is (0,0), and the discharge position of the protective film forming material in the range of X≧0, Y≧0 is determined by the following method. The position of the step is (Xi,Yi), and the radius of the droplet after the filling time is (E). If the angle between the normal to the approximation curve of the step at the step position (Xi,Yi) and the line passing through the center of the droplet and parallel to the X axis is Θ, the coordinate of the discharge position of the protective film forming material is (Xi-EcosΘ, Yi-EsinΘ). Furthermore, if the discharge accuracy of the protective film forming material in the X direction is X' and the discharge accuracy in the Y direction is Y', the coordinate of the discharge position of the protective film forming material taking into account the discharge accuracy can be expressed as (Xi-EcosΘ-X', Yi-EsinΘ-Y').

[0039] Using the same calculation, the ejection positions of the protective film forming material in the other X and Y regions are as follows: If X≧0 and Y<0, then (Xi-EcosΘ-X', Yi+EsinΘ+Y') If X<0, Y≧0, then (Xi+EcosΘ+X',Yi-EsinΘ-Y') If X<0, Y<0, then (Xi+EcosΘ+X', Yi+EsinΘ+Y') It can be expressed as:

[0040] A protective film is formed by discharging a protective film forming material at coordinates, and exposing the material after a filling time has elapsed.

[0041] Next, the region including the step portion is etched for a period of time required to reduce the unevenness, and then the protective film is peeled off.

[0042] This method makes it possible to reduce unevenness at the step positions and to perform processing with minimal change in shape in other portions.

[0043] In the above-described embodiment, a molding technique using imprinting has been described in detail, but the pretreated substrate of the present invention is not limited to this, and can also be used as a pretreated substrate for performing a process to planarize the substrate surface using a superstrate having a flat surface instead of an imprint mold.

[0044] (Production method of the article) The pattern of the cured product formed by using the imprinting apparatus is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. The articles include electric circuit elements, optical elements, MEMS, recording elements, sensors, and molds. Examples of the electric circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensors, and FPGA. Examples of the molds include molds for imprinting.

[0045] The pattern of the cured product is used as it is as at least a part of the component of the article, or is used temporarily as a resist mask. After etching or ion implantation is performed in the substrate processing step, the resist mask is removed. Further, well-known processes for processing the substrate include etching, resist stripping, dicing, bonding, packaging, etc.

[0046] Next, a specific method for manufacturing the article will be described. As shown in Fig. 6(a), a substrate 1z such as a silicon wafer is prepared on the surface of which a workpiece 2z such as an insulator is formed, and then an imprint material 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, a state in which a plurality of droplets of the imprint material 3z are applied onto the substrate is shown.

[0047] As shown in Fig. 6(b), the imprinting mold 4z is placed so that the side on which the concave-convex pattern is formed faces the imprinting material 3z on the substrate. As shown in Fig. 6(c), the substrate 1z to which the imprinting material 3z has been applied is brought into contact with the mold 4z, and pressure is applied. The imprinting material 3z fills the gap between the mold 4z and the workpiece 2z. When light is irradiated through the mold 4z in this state as energy for hardening, the imprinting material 3z hardens.

[0048] 6(d), after the imprint material 3z is cured, the mold 4z and the substrate 1z are separated, and a pattern of the cured product of the imprint material 3z is formed on the substrate 1z. In this cured product pattern, the recesses of the mold correspond to the protrusions of the cured product, and the protrusions of the mold correspond to the recesses of the cured product, i.e., the recessed and protruding pattern of the mold 4z is transferred to the imprint material 3z.

[0049] As shown in FIG. 6(e), when etching is performed using the pattern of the cured material as an etching-resistant mask, the portion of the surface of the workpiece 2z where there is no cured material or where only a thin portion remains is removed, forming a groove 5z. As shown in FIG. 6(f), when the pattern of the cured material is removed, an article having grooves 5z formed on the surface of the workpiece 2z can be obtained. Here, the pattern of the cured material is removed, but it may be used as an interlayer insulating film included in a semiconductor element or the like, that is, a component of an article, without being removed after processing. The article manufacturing method of this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article, compared to conventional methods.

[0050] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

[0051] <Summary of the embodiment> The disclosure herein includes a method for producing a pretreated substrate, a molding apparatus, a molding method, and a method for producing an article.

[0052] (Item 1) A method for manufacturing a pretreated substrate, comprising the steps of: measuring the position of a step disposed in an outer periphery region of the substrate, the step being lower at its outermost periphery than its inner periphery; supplying a protective film forming material to the inside of the measured step of the substrate and forming a protective film such that the protective film forming material is not disposed on an end of the step of the substrate; Etching an edge of a step in the substrate; A method for manufacturing a pretreated substrate comprising the steps of:

[0053] (Item 2) 2. The method for manufacturing a pretreated substrate according to item 1, wherein the step of forming the protective film comprises applying a protective film forming material as droplets, and exposing the material to light after a period of time has elapsed until the gaps between the droplets are filled.

[0054] (Item 3) 3. The method for manufacturing a pretreated substrate described in item 1 or 2, characterized in that the supply position of the protective film forming material is determined based on the measurement result of the position of the step and the value of the radius of the droplet over time after the protective film forming material is supplied, and the protective film formation area is set to be inside the position of the step on the substrate.

[0055] (Item 4) 2. The method for producing a pretreated substrate according to item 1, wherein the step of etching the end of the step is a step of etching a region including the step and the protective film.

[0056] (Item 5) 2. The method for manufacturing an imprinted substrate according to item 1, characterized in that an approximation curve of the positions of the steps on the entire substrate is obtained based on the results of measuring a plurality of positions of the steps.

[0057] (Item 6) 5. The method for producing a pretreated substrate according to any one of items 1 to 4, wherein the pretreated substrate is an imprint substrate for performing imprinting.

[0058] (Item 7) 5. The method for producing a pretreated substrate according to any one of items 1 to 4, wherein the pretreated substrate is a pretreated substrate for performing a planarization treatment.

[0059] (Item 8) a measuring unit arranged in an outer peripheral region of the substrate, the measuring unit measuring a position of a step where the outermost periphery is lower than the inner side; a supply unit that supplies a protective film forming material to the inside of the measured step of the substrate, A molding apparatus for molding a curable composition using a pretreated substrate in which the step has been etched.

[0060] (Item 9) 9. The molding apparatus according to item 8, which imprints the curable composition applied to the pretreated substrate using an imprint mold.

[0061] (Item 10) 8. A molding method comprising a step of molding a curable composition supplied to a pretreated substrate produced by the method according to any one of items 1 to 7.

[0062] (Item 11) Item 11. The molding method according to item 10, comprising the step of imprinting the curable composition applied to the pretreated substrate using an imprint mold.

[0063] (Item 12) A step of molding the curable composition supplied to a pretreated substrate produced by the production method according to any one of items 1 to 7; Etching the pretreated substrate through the curable composition; A method for producing an article having the following structure:

[0064] (Item 13) Item 13. The method for producing an article according to item 12, wherein the molding step is a step of imprinting the curable composition supplied to the pretreated substrate using an imprint mold. [Explanation of symbols]

[0065] 1 Imprinting device 2 light source 3. Substrate 4 Board holding part 5 Material supply section 6. Board Measurement Section 13 Step 14 Imprint material 15 Mold 16 Filling failure

Claims

1. A method for manufacturing a pretreated substrate, comprising the steps of: measuring the position of a step disposed in an outer periphery region of the substrate, the step being lower at its outermost periphery than its inner periphery; supplying a protective film forming material to the inside of the measured step of the substrate and forming a protective film such that the protective film forming material is not disposed on an end of the step of the substrate; Etching an edge of a step in the substrate; A method for manufacturing a pretreated substrate comprising the steps of:

2. 2. The method for manufacturing a pretreated substrate according to claim 1, wherein the step of forming the protective film comprises applying a protective film forming material as droplets, and exposing the material to light after a period of time has elapsed until spaces between the droplets are filled.

3. The method for manufacturing a pretreated substrate as described in claim 1, characterized in that the supply position of the protective film forming material is based on the measurement result of the position of the step and the value of the radius of the droplet versus time after the protective film forming material is supplied, and the protective film formation area is set to be inside the position of the step on the substrate.

4. The method for manufacturing a pretreated substrate according to claim 1 , wherein the step of etching the end of the step is a step of etching a region including the step and the protective film.

5. The method for manufacturing an imprinted substrate according to claim 1 , further comprising the step of obtaining an approximation curve of the positions of the steps on the entire substrate based on the results of measuring a plurality of positions of the steps.

6. The method for producing a preprocessed substrate according to claim 1 , wherein the preprocessed substrate is a substrate for imprinting.

7. The method for manufacturing a pretreated substrate according to claim 1 , wherein the pretreated substrate is a pretreated substrate for performing a planarization process.

8. a measuring unit arranged in an outer peripheral region of the substrate, the measuring unit measuring a position of a step where the outermost periphery is lower than the inner side; a supply unit that supplies a protective film forming material to the inside of the measured step of the substrate, A molding apparatus for molding a curable composition using a pretreated substrate in which the step has been etched.

9. The molding apparatus of claim 8 , wherein an imprint mold is used to imprint the curable composition applied to the pretreated substrate.

10. A molding method comprising the step of molding a curable composition supplied to a pretreated substrate produced by the method according to claim 1 .

11. The molding method according to claim 10 , further comprising the step of imprinting the curable composition applied to the pretreated substrate using an imprint mold.

12. A step of molding a curable composition supplied to a pretreated substrate produced by the method according to any one of claims 1 to 7; Etching the pretreated substrate through the curable composition; A method for producing an article having the following structure:

13. The method for manufacturing an article according to claim 12 , wherein the molding step is a step of imprinting the curable composition supplied to the pretreated substrate using an imprint mold.

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