Electroforming master, method of manufacturing electroforming master, and method of manufacturing electroformed product

Abstract

To provide a master disk for electroforming, a production method of the master disk for electroforming, and a production method of an electroformed object using the master disk for electroforming, which have excellent adhesive properties to the electroformed object and can suppress the peeling of the electroformed object in growth.SOLUTION: A master disk for electroforming comprises a substrate including an n-type semiconductor, on a surface of which a pattern is laid and an oxide film is formed. A thickness of the oxide film is 18Å or smaller. The master disk for electroforming, a production method of the master disk for electroforming, and a production method of an electroformed object using the master disk for electroforming are provided.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an electroforming master, a method for manufacturing an electroforming master, and a method for manufacturing an electroformed product. [Background technology]

[0002] Electroforming is widely used as a method for producing parts, dies, etc. having various shapes. In electroforming, a master having a pattern on its surface is used, and an electroformed product is produced by electroforming nickel or the like onto the master. For example, Patent Document 1 discloses an electroforming mold comprising a plurality of mold structures made of silicon formed on a substrate made of silicon and having side walls that are approximately perpendicular to the substrate surface, an insulator covering the side walls and upper surfaces of the mold structures, and a support substrate that supports the mold structures via an insulating connection layer, the insulating connection layer connecting the lower surface of the mold structures to the upper surface of the support substrate, and having a recess formed by removing at least a portion of the insulating connection layer that is not in contact with the mold structures.

[0003] An oxide film forms on the surface of the master over time, and the presence of this oxide film between the growing electroformed product and the master reduces the adhesive strength of the electroformed product to the master, which could lead to peeling of the electroformed product during production. For this reason, as described in Patent Document 2, the oxide film is removed from the master using an acid such as hydrofluoric acid before producing the electroformed product. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-256110 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-287216 Summary of the Invention [Problem to be solved by the invention]

[0005] For the purpose of controlling the shape of the electroformed product, a pattern formed of an insulating film may be provided on the surface of the master. The present inventors have found that the removal of an oxide film using an acid is difficult to control, and that if an oxide film is removed using an acid from a master having a pattern formed from an insulating film, there is a risk that the pattern may also be removed. The inventors then discovered that by adjusting the thickness of the oxide film on the surface of the substrate of the electroforming master, it is possible to improve the adhesion of the electroformed product to the electroforming master without removing the oxide film with acid.

[0006] An object of one embodiment of the present disclosure is to provide an electroforming master that has excellent adhesion to an electroformed product and is capable of suppressing peeling of the electroformed product during growth, a method for manufacturing the electroforming master, and a method for manufacturing an electroformed product using the electroforming master. [Means for solving the problem]

[0007] The specific means for solving the problems are as follows: <1> An electroforming master comprising a substrate including an n-type semiconductor and having a pattern on its surface, an oxide film formed on the surface, and the oxide film having a thickness of 18 Å or less. <2> The oxide film contains a hydroxyl group terminal group. <1> The electroforming master according to claim 1. <3> The contact angle of the oxide film with water at 23°C is 40° or less. <1> or <2> The electroforming master according to claim 1. <4> The n-type semiconductor is a silicon-based semiconductor. <1> ~ <3> 10. An electroforming master according to any one of the above. <5> The pattern is formed from an inorganic insulating film. <1> ~ <4> 10. An electroforming master according to any one of the above. <6> The inorganic insulating film is a silicon oxide film. <5> The electroforming master according to claim 1. <7> The inorganic insulating film has a thickness of 0.1 μm or more. <5> or <6> The electroforming master according to claim 1. <8> The thickness of the oxide film is 2 Å or more. <1> ~ <7> 10. An electroforming master according to any one of the above. <9> A method for manufacturing an electroforming master, comprising the steps of: dry etching a surface of a substrate that includes an n-type semiconductor and has a pattern on its surface; and then exposing the substrate to the atmosphere to form an oxide film having a thickness of 18 Å or less. <10> The exposure time is 19 hours or less under the conditions of 1 atmosphere, 23°C ± 2°C, and humidity 50% RH ± 5% RH. <9> A method for producing the electroforming master described in claim 1. <11> The dry etching is performed using one or more gases selected from the group consisting of a rare gas, a fluorine-based gas, and a chlorine-based gas. <9> or <10> A method for producing the electroforming master described in claim 1. <12> the step of forming the oxide film comprises, after dry etching and before exposure to the atmosphere, subjecting the substrate to one or more treatments selected from the group consisting of immersion in a sulfuric acid / hydrogen peroxide mixture, UV ozone treatment, and oxygen gas plasma treatment. <9> ~ <11> 10. A method for producing an electroforming master according to any one of the above. <13> the above <1> ~ <8> a step of forming an electroformed product on the surface of the electroforming master on which the oxide film is formed in an electroforming solution, using the electroforming master described in any one of the above items as a cathode; and A step of peeling the electroformed product from the electroforming master. A method for manufacturing an electroformed product, comprising: <14> a step of cleaning the electroforming master after the peeling step, a cycle including the cleaning step, the electroformed product forming step, and the peeling step is repeated a plurality of times; <13> A method for producing an electroformed product according to claim 1. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide an electroforming master that has excellent adhesion to an electroformed product and is capable of suppressing peeling of the electroformed product during growth, a method for manufacturing the electroforming master, and a method for manufacturing an electroformed product using the electroforming master. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of an electroforming master according to the present disclosure. [Figure 2] 2(A) to 2(E) are schematic cross-sectional views showing one embodiment of a method for producing a substrate having a pattern on its surface. [Figure 3] 1 is a schematic cross-sectional view showing an embodiment of an electroforming master and an electroformed product formed on the surface of the electroforming master. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] In the present disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value of that numerical range may be replaced with a value shown in the examples.

[0011] In this disclosure, "n-type semiconductor" refers to a semiconductor in which free electrons are used as carriers to carry electric charge.

[0012] In the present disclosure, the "thickness of the oxide film" is measured as follows. The thickness of the oxide film is measured using an ellipsometer in the atmosphere at 23°C ± 2°C and 50% RH ± 5% RH. The ellipsometer can be an automatic ellipsometer DVA-36L manufactured by Mizojiri Optical Industries Co., Ltd. or a device of similar caliber. The thickness of the inorganic insulating film and the like, which will be described later, is also measured by the above method.

[0013] (Electroforming master) The electroforming master of the present disclosure includes a substrate that includes an n-type semiconductor and has a pattern on its surface, and an oxide film is formed on the surface, with the oxide film having a thickness of 18 Å or less.

[0014] The electroforming master of the present disclosure has excellent adhesion to the electroformed product, and can prevent the electroformed product from peeling off during growth.

[0015] The reason for the above effect is presumed to be as follows, but is not limited to this. The thickness of the oxide film formed on the surface of the substrate included in the electroforming master of the present disclosure is 18 Å or less. By keeping the thickness of the oxide film 18 Å or less, it is presumed that the electrostatic attraction between the substrate and the electroformed product growing on the oxide film is suppressed from decreasing, and therefore the electroforming master of the present disclosure has excellent adhesion to the electroformed product, and peeling of the electroformed product during growth is suppressed. Furthermore, if an oxide film is not formed on the surface of the electroforming master, it becomes difficult to separate the manufactured electroformed product from the electroforming master, and there is a risk of cohesive failure of the electroformed product or the electroforming master occurring. It is presumed that the presence of an oxide film improves the adhesive strength between the electroformed product and the electroforming master, enabling separation to be performed while suppressing the occurrence of cohesive failure.

[0016] The pattern provided on the surface of the substrate is not particularly limited, and is preferably adjusted appropriately depending on the application of the electroformed product to be manufactured. The method of forming the pattern will be described later.

[0017] From the viewpoint of improving adhesion between the electroforming master of the present disclosure and the electroformed product, the thickness of the oxide film is preferably 17 Å or less, more preferably 15 Å or less, even more preferably 13 Å or less, and particularly preferably 10 Å or less. The thickness of the oxide film is preferably 0.5 Å or more, more preferably 1 Å or more, even more preferably 2 Å or more, and particularly preferably 5 Å or more. If an oxide film is not formed on the surface of the electroforming master, it will be difficult to separate the produced electroformed product from the electroforming master, and there is a risk of cohesive failure of the electroformed product or the electroforming master. When the thickness of the oxide film is 0.5 Å or more, the adhesive strength between the electroformed product and the electroforming master is good, and peeling can be performed while suppressing the occurrence of cohesive failure and the like. Furthermore, by making the oxide film 0.5 Å or thicker, when an electroformed product is formed on the oxide film, it is possible to prevent air bubbles from becoming trapped between the oxide film and the electroformed product, thereby preventing trapped air bubbles from increasing the surface roughness of the electroformed product and causing defects. The thickness of the oxide film can be adjusted by adjusting the exposure time of the substrate to the atmosphere after dry etching, which will be described later.

[0018] The oxide film preferably contains hydroxyl terminal groups (-OH). By including hydroxyl terminal groups (-OH) in the oxide film, the hydrophilicity of the oxide film surface can be improved, and the entrapment of the above-mentioned air bubbles can be suppressed. This can prevent the entrapped air bubbles from increasing the surface roughness of the electroformed product and causing defects.

[0019] Whether or not an oxide film has a hydroxyl terminal group is determined by X-ray photoelectron spectroscopy (XPS). Specifically, an X-ray photoelectron spectrometer is used under the following measurement conditions to confirm whether or not hydroxyl groups derived from silanol groups are detected on the oxide film surface. In XPS, the X-ray source is monochromated Al Kα rays, the X-ray spot diameter is 100 μm, and the photoelectron escape angle is 90° (tilt of the detector relative to the oxide film surface). For XPS, an X-ray photoelectron spectrometer is used, and for example, Axis-Ultra manufactured by Shimadzu Corporation or an equivalent device can be used.

[0020] The contact angle of the oxide film with water at 23°C is preferably 40° or less, more preferably 35° or less, even more preferably 30° or less, and particularly preferably 20° or less. By making the contact angle of the oxide film with water at 23°C 40° or less, it is possible to suppress the entrapment of the above-mentioned air bubbles, thereby preventing the entrapped air bubbles from increasing the surface roughness of the electroformed product and causing defects.

[0021] In the present disclosure, the "contact angle of an oxide film with water at 23°C" is measured by the air-drop method using a contact angle meter with a water droplet volume of 1 μL. As the contact angle meter, for example, DMo-701 manufactured by Kyowa Interface Science Co., Ltd. or a device equivalent thereto can be used.

[0022] The n-type semiconductor contained in the substrate is not particularly limited, and conventionally known n-type semiconductors can be used. Examples of n-type semiconductors include silicon compounds (silicon-based semiconductors), fullerene compounds, electron-deficient phthalocyanine compounds, fused polycyclic compounds (naphthalene tetracarbonyl compounds, perylene tetracarbonyl compounds, etc.), TCNQ compounds (tetracyanoquinodimethane compounds, etc.), polythiophene compounds, benzidine compounds, carbazole compounds, and phenanthroline compounds. Among the above, from the viewpoint of improving adhesion to the electroformed product, the n-type semiconductor is preferably a silicon-based semiconductor. Examples of silicon-based semiconductors include single crystal silicon, polycrystalline silicon, amorphous silicon, and polysilicon.

[0023] From the viewpoint of improving adhesion to the electroformed product, the thickness of the substrate is preferably 50 μm to 1,500 μm, more preferably 300 μm to 1,000 μm, and even more preferably 500 μm to 750 μm.

[0024] The pattern provided on the surface of the substrate is preferably formed from an inorganic insulating film. By forming the pattern on the surface of the substrate from an inorganic insulating film, electroforming of nickel or the like on the pattern can be suppressed, and an electroformed product having a desired shape can be formed.

[0025] The inorganic insulating film forming the pattern is preferably a silicon oxide film, for example, an inorganic insulating film formed from silane dioxide. When the inorganic insulating film is a silicon-based oxide film, electroforming of nickel or the like on the pattern can be further suppressed, making it possible to produce an electroformed product with a desired shape. Furthermore, when the inorganic insulating film is a silicon-based oxide film, adhesion to the substrate can be improved. Furthermore, an electroforming master including a substrate having the above-described pattern can prevent the pattern from peeling off when the formed electroformed product is peeled off from the electroforming master, eliminating the need to re-form the pattern, making it suitable for continuous production of electroformed products and preferable. As the silicon oxide film, a film containing an oxide of the above silicon semiconductor can be used.

[0026] From the viewpoint of suppressing electroforming of nickel or the like, the thickness of the inorganic insulating film is preferably 0.1 μm or more, more preferably 0.5 μm or more, and even more preferably 1 μm or more. The upper limit of the thickness of the inorganic insulating film is not particularly limited, and can be, for example, 10 μm or less.

[0027] An embodiment of the electroforming master of the present disclosure will be described below with reference to FIG. The electroforming master 10 of the present disclosure includes a substrate 12 having an oxide film 11 formed on its surface. The substrate 12 includes a pattern 13 on its surface. In FIG. 1, the oxide film 11 is not formed on the surface of the pattern 13, but the oxide film 11 may be formed on a part of or the entire surface of the pattern 13.

[0028] (Method of manufacturing electroforming master) The method for manufacturing an electroforming master of the present disclosure includes a step of dry-etching the surface of a substrate that includes an n-type semiconductor and has a pattern on its surface, and then exposing the substrate to the atmosphere to form an oxide film having a thickness of 18 Å or less.

[0029] According to the method for manufacturing an electroforming master of the present disclosure, it is possible to manufacture an electroforming master that has excellent adhesion to the electroformed product and can prevent the electroformed product from peeling off during growth. The reason for the above effect is presumed to be as follows, but is not limited to this. The electroforming master manufactured by the method for manufacturing an electroforming master according to the present disclosure includes a substrate on the surface of which an oxide film having a thickness of 18 Å or less is formed. By making the oxide film thickness 18 Å or less, it is possible to prevent a decrease in the electrostatic attraction between the substrate and the electroformed product growing on the oxide film. This is thought to result in excellent adhesion between the electroforming master and the electroformed product, preventing the electroformed product from peeling off during growth.

[0030] Furthermore, with the electroforming master manufactured by the electroforming master manufacturing method of the present disclosure, when an electroformed product is formed on an oxide film, it is possible to prevent air bubbles from becoming trapped between the oxide film and the electroformed product, thereby preventing trapped air bubbles from increasing the surface roughness of the electroformed product and causing defects. The reason for the above effect is presumed to be as follows, but is not limited to this. According to the method for manufacturing an electroforming master disclosed herein, an electroforming master can be manufactured by dry etching a substrate and exposing it to the atmosphere without using an acid such as hydrofluoric acid, and therefore the oxide film surface tends to have excellent hydrophilicity. The excellent hydrophilicity of the oxide film can prevent air bubbles from becoming trapped between the oxide film and the electroformed product when an electroformed product is formed on the oxide film, thereby preventing the trapped air bubbles from increasing the surface roughness of the electroformed product and causing defects.

[0031] The method for dry etching the surface of the substrate is not particularly limited, and can be carried out using a conventionally known etching gas. Dry etching of the substrate can remove the oxide film already formed on the substrate surface, and exposure to the atmosphere can form an oxide film with a thickness of 18 Å or less on the substrate surface. For dry etching, it is preferable to use one or more gases selected from the group consisting of rare gases, fluorine-based gases, and chlorine-based gases. By using such gases, it is possible to prevent an oxide film from remaining on the surface of the substrate. As the rare gas, He gas, Ar gas, or the like can be used. As the fluorine-based gas, SF6 gas, CF4 gas, CHF3 gas, C2F6 gas, C4F8 gas, etc. can be used. As the chlorine-based gas, Cl2 gas, CHCl3 gas, CH2Cl2 gas, CCl4 gas, BCl3 gas, etc. can be used. Among the above, SF6 gas or Ar gas is preferred from the viewpoint of being able to make the surface of the electroformed product a mirror finish.

[0032] From the viewpoint of improving the adhesion of the electroforming master to the electroformed product, the exposure time to the atmosphere is preferably 24 hours or less, more preferably 19 hours or less, even more preferably 5 hours or less, and particularly preferably 1 hour or less, under conditions of 1 atmosphere, 23°C ± 2°C, and humidity 50% RH ± 5% RH, and may be 10 minutes or less. The lower limit of the exposure time to the atmosphere is not particularly limited, and can be, for example, 1 minute or more.

[0033] The step of forming an oxide film may include, after dry etching and before exposure to the atmosphere, subjecting the substrate to one or more treatments selected from the group consisting of immersion in sulfuric acid / hydrogen peroxide, UV (ultraviolet) ozone treatment, and oxygen gas plasma treatment. By including the above-described treatment in the step of forming an oxide film, the hydrophilicity of the oxide film surface can be improved, and when an electroformed product is produced using an electroforming master produced by the production method of the present disclosure, it is possible to suppress the entrapment of air bubbles between the oxide film and the electroformed product, thereby suppressing the increase in surface roughness of the electroformed product due to the entrapped air bubbles and the occurrence of defects.

[0034] The substrate having a pattern on its surface used to manufacture the electroforming master may be a commercially available product, or may be manufactured by a conventional method. Hereinafter, one embodiment of a method for manufacturing a substrate having a pattern on its surface will be described with reference to FIGS. 2(A) to 2(E).

[0035] First, a base material 20 containing a silicon-based semiconductor is prepared, and one surface of the base material 20 is thermally oxidized to form an inorganic insulating film 21, which is a silicon-based oxide film (FIG. 2(A)).

[0036] A resist is applied to the surface of the inorganic insulating film 21 to form a resist film 22 (FIG. 2(B)). The resist is not particularly limited, and ultraviolet curable resins that have been conventionally used in photolithography can be used.

[0037] The resist film 22 is exposed to light in a pattern (FIG. 2(C)). The patterned exposure of the resist film 22 can be carried out by using a conventionally known patterning mask 23, as shown in FIG. 2(C).

[0038] After the exposure, the exposed portion of the resist film is removed by washing using a conventionally known developer to form a resist mask 24 (FIG. 2(D)).

[0039] After forming the resist mask 24, the inorganic insulating film 21 formed in the areas where the resist mask 24 is not formed is removed by dry etching, and then the resist mask 24 is peeled off to obtain a substrate 26 having a pattern 25 (Figure 2(E)).

[0040] (Method of manufacturing electroformed products) The method for producing an electroformed product according to the present disclosure includes the steps of: using the electroforming master as a cathode; and forming an electroformed product on the surface of the electroforming master on which an oxide film has been formed in an electroforming solution; The process includes a step of peeling the electroformed product from the electroforming master.

[0041] According to the method for manufacturing an electroformed product of the present disclosure, peeling of the electroformed product from the electroforming master during growth can be suppressed.

[0042] The reason for the above effect is presumed to be as follows, but is not limited to this. The electroforming master used in the method for producing an electroformed product according to the present disclosure includes a substrate, on whose surface an oxide film having a thickness of 18 Å or less is formed. By making the oxide film 18 Å or less in thickness, it is possible to prevent a decrease in the electrostatic attraction between the substrate and the electroformed product growing on the oxide film. This is thought to result in excellent adhesion between the electroforming master and the electroformed product, preventing the electroformed product from peeling off during growth.

[0043] [Electroforming process] An electroformed product can be formed by passing a current through the electroforming master described above as a cathode in an electroforming liquid. The electroforming liquid to be used is not particularly limited, and for example, a nickel sulfamate electroforming liquid can be used. There are no particular limitations on the material that can be used as the anode, and for example, a nickel plate can be used.

[0044] The current density and duration of current application are not particularly limited, and are preferably adjusted appropriately depending on the desired size of the electroformed product to be formed. For example, the current density is 5A / dm 2 ~10A / dm 2 The energization time can be set to 10 minutes to 2 hours.

[0045] The electroformed product may be formed only on the surface of the oxide film, or may be formed such that an electroformed product 32 grown on the surface of an oxide film 31 extends over a pattern 33 formed by an inorganic insulating film (so-called overgrowth), as shown in Fig. 3. In Fig. 3, the substrate is designated by the reference numeral 34.

[0046] [Process for removing electroformed products] The method for separating the electroformed product from the electroforming master is not particularly limited, and can be carried out by a conventionally known method.

[0047] [Process for cleaning the electroforming master] The method for producing an electroformed product according to the present disclosure can include a step of cleaning the electroforming master after the step of peeling the electroformed product from the electroforming master. In the method for producing an electroformed product according to the present disclosure, it is preferable to perform a cycle including a cleaning step, a step of forming an electroformed product, and a step of peeling multiple times.

[0048] The method for cleaning the electroforming master is not particularly limited and can be performed by a conventionally known method. For example, the electroforming master can be cleaned by using a cleaning solution containing Caro's acid. An example of a cleaning solution containing Caro's acid is SH303 manufactured by Kanto Chemical Co., Ltd. Examples include: [Example]

[0049] The above embodiment will be specifically described below using examples, but the above embodiment is not limited to these examples.

[0050] Example 1 A substrate (725 μm thick) containing a silicon-based semiconductor was prepared, and one surface of the substrate was thermally oxidized to form a 2 μm thick inorganic insulating film, which was a silicon-based oxide film containing silane dioxide.

[0051] A resist (MICROPOSIT, manufactured by Rohm and Haas Electronic Materials Co., Ltd.) was spin-coated onto the surface of the inorganic insulating film. TM S1818G) was applied to form a resist film, which was then exposed to light in a pattern. After exposure, the exposed areas of the resist film were removed by washing with a developer, forming a resist mask on the inorganic insulating film.

[0052] After forming the resist mask, the inorganic insulating film formed on the portion of the substrate where the resist mask was not formed was removed by dry etching using a mixed gas of CHF3 and CF4. Next, the resist mask was peeled off to prepare a substrate having a pattern formed from an inorganic insulating film. The dry etching conditions were CHF3 gas flow rate of 24 × 10 -4 m 3 / hr, CF4 gas flow rate 6 x 10 -4 m 3 / hr, pressure 0.6 Pa, inductively coupled plasma (ICP: Industry Coupled Plasma) 200 W, bias 30 W, lower cooling temperature 50°C, treatment time 80 minutes

[0053] The substrate was left standing in an environment of 23°C and 50% RH for 168 hours. After being left standing, the surface of the substrate on which the pattern was to be formed was subjected to dry etching using SF6 gas to remove a 25 Å thick oxide film formed on the surface on which the pattern was to be formed. After removing the oxide film, the substrate was exposed to the air for 5 minutes to form an oxide film on the surface, thereby obtaining an electroforming master. The dry etching conditions were SF6 gas flow rate 6×10 -4 m 3 / hr, pressure 0.6 Pa, inductively coupled plasma (ICP: Industry Coupled Plasma) 500 W, bias 15 W, and treatment time 1 minute. The atmospheric conditions for exposure were 1 atmosphere, 23°C, humidity 50%RH, and exposure time 5 minutes.

[0054] The thickness of the oxide film formed on the surface of the electroforming master was measured in the atmosphere at 23°C and 50% RH using an ellipsometer (automatic ellipsometer DVA-36L manufactured by Mizojiri Optical Co., Ltd.), and was found to be 8 Å.

[0055] <Examples 2 to 5> An electroforming master was produced in the same manner as in Example 1, except that the exposure time to the atmosphere was changed to the time shown in Table 1. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0056] Example 6 An electroforming master was produced in the same manner as in Example 1, except that the surface of the substrate on which the pattern was to be formed was dry etched using SF6 gas and CHF3 gas. The dry etching conditions were SF6 gas flow rate 6×10 -4 m 3 / hr, CHF3 gas flow rate 24 x 10 -4 m 3 / hr, pressure 0.6Pa, inductively coupled plasma 500W, bias 15W, The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0057] Example 7 An electroforming master was produced in the same manner as in Example 1, except that the surface of the substrate on which the pattern was to be formed was dry etched using Ar gas. The dry etching conditions were Ar gas flow rate of 6 × 10 -3 m 3 / hr, pressure 3 Pa, inductively coupled plasma 300 W, bias 120 W, treatment time 1 minute. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0058] Example 8 An electroforming master was manufactured in the same manner as in Example 1, except that the surface of the substrate on which the pattern was to be formed was dry etched using SF6 gas and then subjected to oxygen gas plasma treatment before exposure to the atmosphere. The conditions for oxygen gas plasma treatment were: O2 gas flow rate 18 × 10 -3 m 3 / hr, pressure 10 Pa, inductively coupled plasma 800 W, bias 100 W, treatment time 1 minute. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0059] Example 9 An electroforming master was produced in the same manner as in Example 1, except that the surface of the substrate on which the pattern was to be formed was dry-etched using SF6 gas, and then immersed in sulfuric acid / hydrogen peroxide before being exposed to the atmosphere. The immersion in the sulfuric acid / hydrogen peroxide mixture was carried out using SH303 manufactured by Kanto Chemical Co., Inc., under the conditions of an immersion time of 20 minutes and a water rinse time of 5 minutes. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0060] Example 10 An electroforming master was produced in the same manner as in Example 1, except that the surface of the substrate on which the pattern was to be formed was dry etched using SF6 gas and then subjected to UV ozone treatment before exposure to the atmosphere. The UV ozone treatment was carried out using a UV ozone cleaning device manufactured by Sen Special Light Sources Co., Ltd., by irradiating the sample with ultraviolet light from a low-pressure mercury lamp (wavelength 185 nm) for 5 minutes. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0061] <Comparative Example 1> An electroforming master was obtained in the same manner as in Example 1, except that the surface of the substrate on which the pattern was to be formed was not subjected to dry etching using SF6 gas or exposure to the atmosphere. Since dry etching and exposure to the atmosphere were not performed, the surface treatment method and the exposure time to the atmosphere are marked with "-" in Table 1. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0062] <Comparative Example 2> An electroforming master was obtained in the same manner as in Example 1, except that the exposure time to the atmosphere was changed to 116 hours. The thickness of the oxide film was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0063] <Comparative Example 3> Except for not exposing to the atmosphere, an electroforming master was obtained in the same manner as in Example 1. Since no exposure to the atmosphere was performed, the exposure time to the atmosphere is marked with "-" in Table 1. Since no oxide film was found to be formed on the electroforming master of Comparative Example 3, the thickness of the oxide film is shown in Table 1 as "-".

[0064] <<Contact angle with water>> The contact angles of the oxide films on the electroforming masters manufactured in the above Examples and Comparative Examples with water were measured and are shown in Table 1. The contact angle with water was measured by the air-drop method in an environment of 23° C. using DMo-701 manufactured by Kyowa Interface Science Co., Ltd. The volume of the water droplet used for the measurement was 1 μL.

[0065] <<Identifying the terminal group>> The terminal groups on the surface of the oxide film provided on the electroforming masters manufactured in the above Examples and Comparative Examples were identified as follows. First, the electroforming masters were immersed in trifluoroacetic anhydride, and then the presence of trifluoromethyl groups was detected by XPS to identify the terminal groups on the oxide film surface. The terminal groups on the oxide film surface of the electroforming masters manufactured in the above examples and comparative examples were all hydroxyl groups. In XPS, the X-ray source is monochromated Al Kα rays, the X-ray spot diameter is 100 μm, and the photoelectron escape angle is 90° (tilt of the detector relative to the oxide film surface). For XPS, an X-ray photoelectron spectrometer (Shimadzu Corporation, Axis-Ultra) was used. Since no oxide film was found to be formed on the electroforming master of Comparative Example 3, in Table 1 the terminal group is indicated as "-".

[0066] <<Evaluation of Adhesion Between Electroforming Master and Electroformed Product>> The electroforming masters manufactured in the above Examples and Comparative Examples were used as cathodes and immersed in nickel electroforming solution, and a current of 6.2 A / dm 2 By passing a current through the master for 50 minutes at a current density of 1000 kJ / s, nickel was electroformed onto the oxide film-formed surface of the master, producing an electroformed product with a thickness of 50 μm. A nickel plate was used as the anode. Current density is 6.2A / dm 2 The current application time was changed to 10 minutes, and an electroformed product having a thickness of 10 μm was produced in the same manner as above. The electroformed products were visually observed and evaluated based on the following criteria. The evaluation results are shown in Table 1. In Comparative Example 3, neither the 50 μm-thick electroformed product nor the 10 μm-thick electroformed product was observed to peel from the electroforming master, but cohesive failure of the electroformed product or the electroforming master occurred when these electroformed products were peeled from the electroforming master. (Evaluation criteria) A: No peeling from the electroforming master was observed in either the 50 μm thick electroformed product or the 10 μm thick electroformed product. B: No peeling of the 10 μm thick electroformed product from the electroforming master was observed, but peeling of the 50 μm thick electroformed product from the electroforming master was observed. C: Peeling from the electroforming master was confirmed in both the 50 μm thick electroformed product and the 10 μm thick electroformed product.

[0067] <<Surface roughness Ra>> The electroformed product produced to evaluate the adhesion between the electroforming master and the electroformed product was peeled from the electroforming master, and the surface roughness Ra of the peeled surface of the electroformed product was measured using a non-contact 3D surface roughness / shape measuring instrument (New View 7300, manufactured by ZYGO Corporation). The measurement results are shown in Table 1. In addition, for Comparative Examples 1 and 2, in which peeling of the electroformed product from the electroforming master was confirmed during production of the electroformed product, the surface roughness Ra of the electroformed product was not measured, and therefore is indicated as "-" in Table 1. For the Examples and Comparative Examples with an adhesion rating of A, the surface roughness Ra was measured on an electroformed product with a thickness of 50 μm, and for the Examples with an adhesion rating of B, the surface roughness Ra was measured on an electroformed product with a thickness of 10 μm.

[0068] [Table 1]

[0069] As is clear from the results shown in Table 1, the electroforming masters of the examples, which have oxide films with thicknesses of 18 Å or less, have excellent adhesion to the electroformed product and can effectively prevent the electroformed product from peeling off during growth. It is clear that the electroforming master of the comparative example, which has an oxide film with a thickness of 18 Å or more, has a lower adhesive strength with the electroformed product than the electroforming master of the example, and peeling of the electroformed product occurs during growth.

[0070] <<Evaluation of suitability for repeated use>> The suitability for repeated use of the electroforming masters of the examples was evaluated by the following method. First, the electroformed product produced in the evaluation of the adhesion between the electroforming master and the electroformed product was peeled from the electroforming master of Examples 1 to 10, and the electroforming master was cleaned with SH303 manufactured by Kanto Chemical Co., Inc. After cleaning, nickel was electroformed onto the electroforming master by the method described above to produce an electroformed product. One cycle consisted of producing an electroformed product, peeling off the electroformed product, and cleaning the electroforming master, and this cycle was repeated five times. After peeling off the electroformed product, the patterns on the substrate surface of the electroforming master of each example were visually observed, and it was confirmed that none of the patterns had peeled off, confirming that the product could be used repeatedly. Furthermore, the adhesion between the electroforming master and the electroformed product produced in each cycle was evaluated. The evaluation results were the same for each example, confirming that the adhesion between the electroformed product and the master did not decrease with repeated use. [Explanation of symbols]

[0071] 10: electroforming master, 11: oxide film, 12: substrate, 13: pattern, 20: substrate, 21: inorganic insulating film, 22: resist film, 23: patterning mask, 24: resist mask, 25: pattern, 26: substrate with pattern, 31: oxide film, 32: electroformed product, 33: pattern, 34: substrate

Claims

1. a substrate including an n-type semiconductor and having a pattern on a surface thereof, an oxide film formed on the surface thereof, and a thickness of the oxide film being 2 Å or more and 17 Å or less; The electroforming master, wherein the n-type semiconductor is a silicon-based semiconductor.

2. The electroforming master according to claim 1 , wherein the oxide film contains a hydroxyl group terminal group.

3. 3. The electroforming master according to claim 1, wherein the oxide film has a contact angle with water at 23° C. of 40° or less.

4. 4. The electroforming master according to claim 1, wherein the pattern is formed from an inorganic insulating film.

5. 5. The electroforming master according to claim 4, wherein the inorganic insulating film is a silicon oxide film.

6. 6. The electroforming master according to claim 4, wherein the inorganic insulating film has a thickness of 0.1 μm or more.

7. a step of dry-etching a surface of a substrate including an n-type semiconductor and having a pattern on the surface, and then exposing the surface to air to form an oxide film having a thickness of 2 Å to 17 Å; The method for manufacturing an electroforming master, wherein the n-type semiconductor is a silicon-based semiconductor.

8. 8. The method for manufacturing an electroforming master according to claim 7, wherein the exposure time is 19 hours or less under conditions of 1 atmosphere, 23°C ± 2°C, and humidity of 50% RH ± 5% RH.

9. 9. The method for manufacturing an electroforming master according to claim 7, wherein the dry etching is performed using one or more gases selected from the group consisting of rare gases, fluorine-based gases, and chlorine-based gases.

10. The method for manufacturing an electroforming master according to any one of claims 7 to 9, wherein the step of forming the oxide film comprises, after dry etching and before exposure to the atmosphere, subjecting the base to one or more treatments selected from the group consisting of immersion in a sulfuric acid / hydrogen peroxide mixture, UV ozone treatment, and oxygen gas plasma treatment.

11. a step of using the electroforming master according to any one of claims 1 to 6 as a cathode and forming an electroformed product on the surface of the electroforming master on which the oxide film is formed in an electroforming solution; and A step of peeling the electroformed product from the electroforming master. A method for manufacturing an electroformed product, comprising:

12. a step of cleaning the electroforming master after the peeling step, The method for producing an electroformed product according to claim 11 , wherein a cycle including the cleaning step, the electroformed product forming step, and the peeling step is performed a plurality of times.

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