KR100991693B1 - Mother mold for reproducing a replica mold by electroplating and fabrication method therof - Google Patents

Abstract

The present invention relates to a mother mold for replicating a mold by electroplating and a method of manufacturing the same, and more particularly, a mother mold substrate having a fine pattern; An anti-stick layer formed on a mother mold substrate along the fine pattern and formed of a self-assembled monolayer (SAM) including a fluorinated alkyl silane compound; And a mother mold for replicating the mold by electroplating including a metal seed layer formed on the anti-sticking film, and a method of manufacturing the same.

The mother mold can be separated from the replica mold without damaging the mother mold by a simple physical force when the mold is duplicated by electroplating, and the mother mold can be repeatedly reused after the replication. In addition, the replication mold thus obtained has an inverted pattern without distortion and deformation with respect to the fine pattern of the mother mold even if the fine patterning performed after the conventional replication is not performed again.

Mother mold, replica mold, electroplating, vapor phase self-assembled monolayer

Description

Mother mold for mold duplication by electroplating and manufacturing method thereof {MOTHER MOLD FOR REPRODUCING A REPLICA MOLD BY ELECTROPLATING AND FABRICATION METHOD THEROF}

The present invention can be separated from the duplicate mold without damaging the mother mold with only a simple physical force when the mold is duplicated by electroplating, and the reuse of the mother mold is possible, and the duplicated duplicate mold has a pattern without distortion and deformation. The present invention relates to a mother mold for replicating a mold by electroplating and a method of manufacturing the same.

The mold industry is an essential industry for producing plastic products, sheet metal products, die casting parts, forging parts, etc., which are used in the entire industry. As the demand for automobiles, communication devices, electronic products, semiconductors, machine tools, etc. increases, the demand for molds is also steady. It is increasing.

In particular, in recent years, with the demand for miniaturization of machines and electronic devices, with the advent of high-tech equipment for precision processing and the development of new process technologies, much attention and research have been conducted in the field of ultra-precision processing technology. Using such processing techniques, development of practical micro devices and components such as optical parts, communication parts, and micro molds is actively progressing.

 It is possible to fabricate molds with nano- and micro-level structures using actual semiconductor process technology. The techniques for replicating existing molds include photolithography, etching, and electroplating. need.

In this case, in order to duplicate the mold having a fine pattern, the manufacture of a mother mold using a silicon (Si) substrate is an essential element.

After forming a fine pattern on the silicon wafer through photolithography, it is possible to manufacture a mother mold having a variety of steps through the etching process.

Sputtering is performed on the fabricated silicon mother mold to use a very thin layer of metal as a seed layer so as to increase electrical conductivity. When electroplating is performed using the silicon mother mold thus manufactured, various molds may be manufactured according to electrochemical conditions.

However, in order to obtain a duplicated mold plated on the silicon mother mold after electroplating, it is very difficult to separate it without any influence on the micropattern by simple physical force. Therefore, a well-known silicon etching solution such as potassium hydroxide (KOH) is used. There is a limit to melt the mother mold to remove it.

In other words, in the prior art, only one mold could be duplicated through one mother mold. That is, the disadvantage is that the mother mold and the mold are duplicated at a ratio of 1: 1, and the cost is high due to the characteristics of the prior art in which an additional etching solution (chemical etchant) such as potassium hydroxide for removing the mother mold is required.

In addition, the mold to be plated through the original mother mold has a reversed phase of the fine pattern present on the mother mold, which must be plated again based on the duplicated mold to obtain the actual required pattern.

Thus the primary replicated mold must be very similar to the fine pattern of the mother mold. Therefore, the present inventors proceeded with the research on the release separation technology that can be separated without distortion and deformation of the pattern when manufacturing a duplicate mold, proposed the present invention.

It is an object of the present invention to provide a mold replica mother mold and a method of manufacturing the same, which can be separated without distortion and deformation of a fine pattern formed on the replica mold when the replica mold is manufactured by electroplating using the mother mold. .

In order to achieve the above object,

A mother mold substrate having a fine pattern formed thereon;

An anti-stick layer formed on a mother mold substrate along the fine pattern and formed of a self-assembled monolayer (SAM) including a fluorinated alkyl silane compound; And

A metal seed layer formed on the anti-stick layer

It provides a mother mold for mold replication comprising a.

Also,

S1) forming a fine pattern on the mother mold substrate by a photolithography process;

S2) forming an anti-sticking film made of a self-assembled molecular thin film by a gas phase reaction on the fine pattern; And

S3) depositing a metal on the anti-sticking film to form a metal seed layer

It provides a method for producing a mold mold for mold replication comprising a.

The mother mold according to the present invention can be separated from the replica mold without damaging the mother mold with only a simple physical force when replicating the mold by electroplating. It is also possible to reuse the mother mold repeatedly after replication.

The obtained replication mold has an inverted pattern without distortion and deformation with respect to the fine pattern of the mother mold even if the fine patterning performed after the conventional replication is not performed again.

The present invention is described in more detail below.

Mother mold

The etching solution was used for separation between the mother mold and the replica mold when the replica mold was manufactured by electroplating with a conventional mother mold. As a result, it is difficult to reuse the mother mold and fine patterns formed in the replica mold also cause distortion and deformation. There was.

The present invention provides a mold mold replica mother mold including an anti-stick film to facilitate separation of the mother mold and the replica mold.

1 is a cross-sectional view showing a mother mold according to an embodiment of the present invention.

Referring to FIG. 1, the mother mold 100 is

A mother mold substrate 10 having a fine pattern formed thereon;

An anti-stick layer 20 formed of a self-assembled monolayer (SAM) formed on the mother mold substrate 10 along the fine pattern; And

A metal seed layer 30 formed on the anti-sticking film 20 is included.

Specifically, the mother mold substrate 10 may be any material that is conductive so that the replication mold can be replicated through electroplating. For example, Au, Pt, Ni, Cu, Co, Pd, Al and their A metal substrate comprising one metal selected from the group consisting of a combination; Or Si, Ge, C, Ga, As, P, B, Zn, Se, Cd, Sn, In, SiGe, GaAs, AlGaAs, GaAsP, InAs, Sn, InAsP, InGaAs, AlAs, InP, GaP, ZnSe, CdS And one kind of semiconductor substrate selected from the group consisting of ZnCdS, CdSe, and combinations thereof.

The fine pattern formed on the mother mold substrate 10 has the same pattern as the molded article to be finally obtained, and is obtained in various forms of embossed and engraved.

Particularly, in the present invention, an anti-stick film 20 is formed on the surface of the mother mold substrate 10 in order to separate the mother mold 100 and the replica mold, and in this case, to maximize the release effect using the anti-stick film 20. In order to invent the material and manufacturing method of the membrane through various studies.

The antistic layer is a vapor self-assembled monolayer having a hydrophobic characteristic (see FIG. 11) having a contact angle of 110 ° or more.

In general, self-assembled molecular thin films are self-assembly aligned two-dimensionally on the surface of a substrate by using molecules having relatively long alkyl groups and molecules having functional groups capable of covalent bonding by interacting with the surface of the substrate. By means of the phenomenon it means a monolayer arranged (monolayer) uniformly.

In particular, the vapor phase self-assembled molecular thin film means that precursors such as organic silicon, thiol, amine, and silane organic active materials in liquid state are vaporized at high temperature to spontaneously combine organic active materials on a substrate to form an ultra-thin monomolecular film. do. The vapor self-assembling molecular thin film is very thin, the organic molecular thin film by the appropriate selection of the precursor, but strong adhesion to the substrate can be produced a strong molecular film. In addition, it is possible to easily form a monomolecular film in a relatively simple process compared to other deposition methods.

2 is a schematic diagram showing the formation of gas phase self-assembled molecular thin film.

The precursors used in the gas phase self-assembly molecular thin film may serve as a functional part of the head portion and the intermolecular molecules chemically bonded to the substrate or the body portion interacting with the substrate and van der Waals attraction, and finally, the molecular terminal. It can be divided into the tail part.

As shown in FIG. 2, the head of the precursor is adsorbed and bonded to the surface of the substrate. At this time, the self-assembled molecular thin film is formed by two-dimensional alignment by hydrophobic attraction between the functional groups of the precursor.

The vapor self-assembled molecular thin film can control the formation process at the molecular level, and can selectively change the functional group of the molecule, and can also control it, and it is not only strong bond to the substrate surface but also excellent film stability. The advantage is that it can be easily removed if desired.

The gas phase self-assembled molecular thin film includes an organosilane containing a C1 to C20 fluoroalkyl group, part of which is substituted with fluorine in order to increase release resolution.

The anti-sticking film 20 made of the vapor phase self-assembled molecular thin film has a proper release resolution on the mother mold substrate 10 and has a thickness of 1 to 2 nm to protect the surface of the mother mold even when the mother mold and the replica mold are separated. Is formed. In particular, since the anti-sticking film 20 is made of a nano-level molecular thin film, the step adhesion to the fine patterns with high unevenness is excellent, so that the anti-sticking film 20 may sufficiently serve as the anti-sticking film 20.

On the other hand, the metal seed layer 30 formed on the anti-sticking film 20 is a film used to provide a low electrical resistance path in the electroplating process to be performed later in the manufacture of the replica mold, the material of the replica mold and It contains metals of the same material.

For example, the metal seed layer 30 may be one selected from the group consisting of nickel (Ni), aluminum (Al), copper (Cu), chromium (Cr), titanium (Ti), and alloys thereof. It is formed in the thickness of 50 로-300 Å on the anti-stick film 20.

Method of Manufacturing Mother Mold

As described above, the mother mold used for mold replication by electroplating according to the present invention has a structure in which an anti-stick film and a metal seed layer are formed on the surface thereof, and a method of manufacturing the mother mold will be described below.

Figure 3 is a flow chart showing a step of manufacturing a mother mold according to the present invention, Figures 4 to 8 are schematic diagrams and cross-sectional views for explaining this.

Referring to Figure 3, the mother mold

S1) forming a fine pattern on the mother mold substrate by a photolithography process;

S2) forming an anti-sticking film made of a self-assembled molecular thin film by a gas phase reaction on the fine pattern; And

S3) to deposit a metal on the anti-sticking film to form a metal seed layer.

First, in step S1) a fine pattern is formed on the mother mold substrate by a photolithography process.

Referring to FIG. 5, the photoresist 11 is coated on the mother mold substrate 10.

The photoresist (photoresist, PR, 11) is a kind of photosensitive polymer that a chemical reaction occurs when the light receives a specific wavelength band, a positive photoresist (positive PR) in which a large exposed area reacts with a developer to dissolve And the exposed area is classified as negative photoresist (negative PR) which does not react with the developer.

At this time, the coating is used in a conventional dip coating, doctor blade method, spin coating, spray coating, slit coating, casting method, lamination method or the like.

Subsequently, after the application, the micro pattern may be formed on the mother mold substrate 10 through a conventional photolithography process such as soft bake-> exposure-> development-> hard bake-> etching-> strip process. 13).

Next, in step S2) to form a self-assembled molecular thin film 20 by a gas phase reaction on the fine pattern 13 (see Fig. 7).

The self-assembled molecular thin film is carried out by a gas phase reaction, for example, is prepared through the following steps.

Specifically, the formation of the vapor phase self-assembled monolayer

S2-1) pretreat the mother mold substrate,

S2-2) transfer the mother mold substrate into the chamber where the temperature and pressure are controlled,

S2-3) supplying the fluorinated organic silane precursor gas for forming the self-assembled molecular thin film into the chamber to form a self-assembled molecular thin film on the substrate.

Specifically, pretreatment is performed to form OH groups on the mother mold substrate for efficiently depositing the vapor phase self-assembled monolayer. The pretreatment may be performed by cleaning the mother mold substrate in a Piranha (H ₂ SO ₄ : H ₂ O ₂ = 4: 1) solution for about 10 minutes, or performing an O ₂ plasma treatment for 3 minutes at 500W.

Next, the mother mold substrate is transferred into a chamber in which temperature and pressure are controlled to form a self-assembled molecular thin film.

Control of process conditions is essential to run the process at higher speeds and to form high quality self-assembled molecular thin films. These process conditions can be the pressure and temperature in the chamber and the vapor pressure of the precursor gas, which can be appropriately selected and controlled by those skilled in the art.

For example, the pressure in the chamber is 5 to 50 Torr, preferably 10 to 30 Torr, and the chamber temperature is 130 to 150 ° C., the process temperature and the process pressure are the process temperature and the process pressure which are continuously maintained in the subsequent process, If necessary, the process temperature and the process pressure can be changed.

In this case, the fluorinated organic silane precursor used may be a silane compound containing a C1 to C20 fluoroalkyl group. For example, fluorooctyl trichloro silane (FOTS), trichloro (3, 3,3-trifluoropropyl) silane (FPTS, trichloro (3,3,3-trifluoropropyl) silane), perfluorodecyl trichloro silane (FDTS, perfluorodecyl-trichlorosilane) is possible.

In addition, after forming the self-assembled molecular film, a purge gas is introduced to remove unreacted raw material gases and deposition by-products. The type and injection rate of the purging gas also contribute to the quality of the self-assembled molecular thin film.

Referring to Scheme 1 below, fluorooctyl trichloro silane (FOTS) is used to form a self-assembled molecular thin film on the surface of a Si substrate:

Scheme 1

8 is a schematic view of Scheme 1.

Referring to Scheme 1 and FIG. 8, when FOTS is supplied to a silicon substrate, a self-assembled molecular thin film is formed by reacting OH groups present on the silicon surface with FOTS.

This process is not particularly limited in the present invention, and is carried out using a known device. Such a device is composed of a gas supply device, a deposition chamber, a vacuum device, an automatic control system, a temperature control device, and the like.

Next, in step S3) by depositing a metal on the anti-sticking film 20 to form a metal seed layer 30 of 50 to 300 50m thickness.

The metal seed layer 30 is performed by a conventional deposition method, and the deposition method may be performed by sputtering, CVD, PECVD, PVD, ion beam deposition, or the like.

Replication method using mother mold

The mother mold produced by the above-mentioned manufactures a replica mold using electroplating. The production of a replica mold using such electroplating is widely known in the art, and by using a mother mold on which an anti-sticking film proposed in the present invention is formed as a mother mold to be used, separation of the mother mold and the replica mold becomes easier.

In one example, the replication is performed by immersing the mother mold for mold replication according to the present invention in an electroplating solution, and then performing electroplating to replicate the replication mold from the mother mold, and then separating the two from each other to obtain a replication mold.

The electroplating method is not particularly limited in the present invention, it can be carried out as known in the art.

9 and 10 are cross-sectional views showing a method of replicating a replica mold from a mother mold by an electroplating method.

Referring to FIG. 9, the mother mold 100 is placed in an electrolytic cell 120 in which a plating solution is contained, and the electroplating is performed by connecting the mother mold 100 to the electrode 110.

Metal is deposited from the metal seed layer 30 of the mother mold 120 by the power applied for electroplating to form a replica mold 200. At this time, the replication mold 200 has a fine pattern of a reverse phase with respect to the fine pattern formed on the mother mold 100.

At this time, the strategy for electroplating is performed by continuously applying a DC current (DC) having a current density of 10 to 40 mA / cm ² for 5 to 6 hours. In addition, the plating solution is not particularly limited in the present invention, nickel sulfate drying solution of the composition consisting of nickel sulfate (NiSO ₄ 6H ₂ O), nickel chloride (NiCl ₂ 6H ₂ O), boric acid (H ₃ BO ₃ ) and saccharin Use

When the formation of the replication mold 200 is completed, the mother mold 100 and the replication mold 200 are taken out of the electrolytic cell, and then a physical force is applied to the mother mold 100 and the replication mold 200 as shown in FIG. 10. Disconnect.

As described above, the duplication of the replica mold using the mother mold having the anti-sticking film according to the present invention has the following advantages.

First, it is possible to easily separate even if a small force is applied when separating the mother mold and the replica mold.

Secondly, unlike the conventional mother mold used for one-time use, there is no damage to the mother mold even after the replication of the replica mold, so that it can be reused, which is advantageous in terms of productivity and economy.

Third, there is no distortion and deformation of the fine pattern of the duplicate mold even after separation, unlike the conventional fine pattern process of the duplicate mold, and thus a separate fine pattern process for the duplicate mold is not required.

Fourth, as the anti-sticking film is manufactured in the form of nm ultrafine thin film by the vapor phase self-assembled thin film formation method, it is possible to manufacture a replica mold having a fine pattern of nano and micro units.

Hereinafter, preferred embodiments of the present invention will be described. However, the following embodiments are only preferred embodiments of the present invention, and the present invention is not limited to the following embodiments.

(Example 1)

Manufacture of Mother Mold

After spin-coating on a cleaned p-type Si (100) wafer using AZ 1518 positive photoresist at a speed of 1000 rpm for 30 seconds, a soft bake process was performed at 100 ° C. for 2 minutes.

Next, a biochip Cr mask is placed on the photoresist, irradiated with UV having a wavelength of 365 to 450 nm for 12 seconds, exposed to light, and then immersed in a dedicated developer MIF300 for 1 minute, taken out, washed with ultrapure water, and then moistened. Was removed. Next, a hard bake was performed at 140 ° C. for 10 minutes to completely cure the photoresist. Subsequently, the wet etching process was performed to form a fine pattern, followed by washing with acetone to remove the photoresist pattern.

Next, FOTS was used as a precursor using a vapor deposition self-deposition monolayer deposition equipment (V-SAM, Sorona, Korea), and a vapor deposition self-assembled thin film having a thickness of 1 nm was deposited through the following process.

First, the inside of the vacuum chamber and the tray required for loading the substrate (loading) were washed with acetone, and then the mother mold substrate was loaded into the vacuum chamber to adjust the pressure to 20 torr. Subsequently, after maintaining the temperature in the chamber at 130 to 150 ° C. for 10 minutes or more, the liquid FOTS precursor was injected into the chamber and reacted for 10 minutes.

After the reaction was completed, nitrogen gas was purged inside the vacuum chamber to remove the unreacted raw material gas and the deposition byproduct, thereby forming an anti-stick film.

Next, sputtering was performed on the anti-sticking film using nickel having a deposition rate of 193 μs / min at 2 mTorr at Ar 30 sccm and 300 W DC power to form a metal seed layer of 100 μs, thereby forming a mother mold. Prepared.

Preparation of Replica Nickel Mold

After the mother mold was immersed in an electrolytic cell containing a nickel sulfate dry bath consisting of nickel sulfate 240g / L, nickel chloride 45g / L, boric acid 30g / L, saccharin 2g / L, 40 mA / cm ² A replica mold was made by applying a current density for 5 hours.

After removing the mother mold and the replica nickel mold from the electrolytic cell, the mother mold and the replica nickel mold were separated by hand by pulling on both sides.

Experimental Example 1

In order to find out the hydrophobicity of the anti-sticking film formed in the mother mold, the contact angle was measured using the contact angle measuring device.

FIG. 11 is a photograph showing a contact angle of a mother mold before forming an anti-sticking film, and FIG. 12 is a photograph showing a contact angle of a mother mold on which an anti-sticking film is formed.

Referring to FIG. 11, it can be seen that the water used for the test was completely wet to the mother mold surface with a contact angle of 5 °.

In comparison with FIG. 12, in which the anti-sticking film was formed, it was confirmed that the contact angle had hydrophobicity at 110 °.

Experimental Example 2

In order to confirm the replication characteristics of the replica nickel mold using the mother mold prepared in Example 1, the surface was confirmed by using an optical microscope (L-150A, Nikon, Japan).

13 is an optical micrograph showing the fine pattern of the mother mold, (a) is 200 times, (b) is 500 times, (c) is enlarged 500 times, Figure 14 is a replica nickel replicated using this An optical micrograph showing the fine pattern of the mold, (a) is 200 times, (b) is 500 times, and (c) is enlarged 500 times. The replica nickel mold then has a reversed pattern with respect to the mother mold and is shown in the same phase for convenience.

Referring to FIGS. 13 and 14, it was confirmed that the replica nickel mold has a pattern corresponding to the fine pattern formed on the mother mold, which indicates that the separation process of the mother mold and the replica nickel mold does not have any effect on the fine pattern. it means.

Experimental Example 3

In order to confirm the replication characteristics of the replica nickel mold using the mother mold prepared in Example 1, the surface was confirmed by using an atomic force microscope (AFM, XE-100, PSIA, Korea) equipment.

15A and 15B are AFM images of nanoscale mother molds, and FIGS. 16A and 16B are AFM images of replica nickel molds replicated using the same.

Referring to FIG. 15 and FIG. 16, the surface morphology, the size of the pattern, the step difference, and the like were compared as a result of analyzing the area of 5 μm ² . It can be seen that it has a very accurate shape precision below.

The mother mold according to the present invention can be used for the production of replica molds usable for various moldings.

1 is a cross-sectional view showing a mother mold according to an embodiment of the present invention.

2 is a schematic diagram showing the formation of gas phase self-assembled molecular thin film.

3 is a flow chart showing a step of manufacturing a mother mold according to the present invention.

4 to 8 are schematic views and cross-sectional views for explaining the same.

9 and 10 are cross-sectional views showing a method of replicating a replica mold from a mother mold by an electroplating method.

11 is a photograph showing the contact angle of the mother mold before forming the anti-sticking film.

12 is a photograph showing a contact angle of a mother mold on which an anti-stick film is formed.

13 is an optical micrograph showing the fine pattern of the mother mold, (a) is 200 times, (b) is 500 times, (c) is enlarged 500 times.

Figure 14 is an optical micrograph showing a fine pattern of a replica nickel mold replicated using this, (a) is 200 times, (b) is 500 times, (c) is a magnified picture 500 times.

15 (a) and 15 (b) are AFM images of the mother mold.

16A and 16B are AFM images of replica nickel molds replicated using them.

Claims (13)

In the mother mold for manufacturing a replica mold through an electroplating process, A mother mold substrate having a fine pattern formed thereon; An anti-stick film formed on a mother mold substrate along the fine pattern and formed of a self-assembled monolayer (SAM) including a fluorinated alkyl silane compound, and having a thickness of 1 to 2 nm; And A mother mold for replicating a mold formed on the anti-sticking film and including a metal seed layer having a thickness of 50 to 300 mm 3. The method of claim 1, The mother mold substrate may include at least one metal selected from the group consisting of Au, Pt, Ni, Cu, Co, Pd, Al, and combinations thereof; Or Si, Ge, C, Ga, As, P, B, Zn, Se, Cd, Sn, In, SiGe, GaAs, AlGaAs, GaAsP, InAs, Sn, InAsP, InGaAs, AlAs, InP, GaP, ZnSe, CdS , ZnCdS, CdSe and a mold replica mother mold comprising a semiconductor selected from the group consisting of a combination thereof. delete The method of claim 1, The anti-sticking film is a mold replica mother mold comprising a C1 to C20 fluorinated organic silane compound. The method of claim 1, The anti-sticking film is a mold mold replica mother mold having a contact angle of 110 ° or more with respect to the mother mold substrate. The method of claim 1, Wherein the metal seed layer is nickel (Ni), aluminum (Al), copper (Cu), chromium (Cr), titanium (Ti) and alloys for replica molds that molds thereof. In order to manufacture a mother mold for producing a replica mold through an electroplating process, S1) forming a fine pattern on the mother mold substrate by a photolithography process; S2) forming a self-assembled molecular thin film by a gas phase reaction on the fine pattern, to form an anti-stick film having a thickness of 1 to 2 nm; And S3) A method of manufacturing a mother mold for mold replication according to claim 1, comprising forming a metal seed layer having a thickness of 50 to 300 mm by depositing a metal on the anti-sticking film. The method of claim 7, wherein Further providing a step to increase the aspect ratio of the fine pattern formed by performing dry etching before the step S2) Method for producing a mold for replica mother mold comprising a. The method of claim 7, wherein The fine pattern is a method of manufacturing a mother mold for mold replication is performed by a photolithography process. The method of claim 7, wherein The anti-sticking film S2-1) transfer the mother mold substrate into the chamber in which temperature and pressure are controlled, S2-2) A method of manufacturing a mother mold for mold duplication in which a self-assembled molecular thin film is formed on a substrate by supplying a fluorinated organic silane precursor gas for forming a self-assembled molecular thin film into the chamber. The method of claim 10, The fluorinated organosilane precursor is a silane compound containing a C1 to C20 fluoroalkyl group is a method for producing a mold for replica mother mold. The method of claim 10, The fluorinated organosilane precursors include fluorooctyl-trichloro-silane (FOTS), trichloro (3,3,3-trifluoropropyl) silane (FPTS, trichloro (3,3,3) -trifluoropropyl) silane), perfluorodecyl trichloro silane (FDTS, perfluorodecyl-trichlorosilane) and a method for producing a mother mold for mold replication, which is one selected from the group consisting of a combination thereof. The method of claim 7, wherein The metal seed layer is sputtering, CVD, PECVD, PVD, or ion beam deposition method to be produced by the method of manufacturing a mother mold for mold replication.

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