KR101575879B1 - Patterning method using reversal imprint process - Google Patents

Abstract

The present invention relates to a patterning method using an inverse imprint method. The patterning method according to the present invention can perform the fine patterning process simply and effectively and has the effect of being able to pattern the substrate without performing a subsequent process for removing the residual layer because the residual layer is not left on the transferred pattern.

Description

[0001] The present invention relates to a patterning method using a reverse imprint method,

The present invention relates to a patterning method using an inverse imprint method.

Generally, in the imprint lithography method, UV curable or thermoplastic resin is applied on a substrate in order to obtain fine moldings and patterns on a substrate, and a process such as pressing and curing by a mold is performed. After the process, Leaving a residual layer of resin.

If a patterning operation is required as a second material on the substrate using a mask as a mask, the patterning of the hardened resin, which is the final imprinting result, is performed by oxygen plasma etching as a subsequent process for removing the residual layer. A dry etching process is required. In this case, the pattern of the cured resin pattern, which is the imprinting result in the dry etching process, is also etched at the same time, thereby changing the size of the cured resin pattern and decreasing the perpendicularity of the pattern, thereby hindering the effective performance of the subsequent deposition / lift-off process. In order to prevent this, a method of applying a sacrificial layer to the lower part before applying the hardened resin or a method of protecting the upper end of the hardened resin molding by slanting an inorganic material is used. However, the entire patterning process becomes complicated and takes a long time have.

Therefore, it is urgently required to develop a method capable of fine patterning without additional process such as dry etching process.

The present inventors have been studying a simple and effective fine patterning method. In the course of studying a simple and effective fine patterning method, a low viscosity resin is first applied to an imprint mold, then the substrate is contacted / pressed, ultraviolet rays or heat are applied to transfer the cured resin pattern to the substrate , It is confirmed that the remaining layer is not left on the transferred pattern, so that the patterning can be performed easily without the need of a subsequent process. Thus, the present invention has been completed.

Accordingly, the present invention provides a patterning method using an inverse imprint method.

The present invention provides a patterning method using a simple and effective process by applying a resin to an imprint mold, pressurizing the substrate, and applying ultraviolet rays and heat to transfer the curable resin to the substrate.

The patterning method according to the present invention can perform the fine patterning process simply and effectively and has the effect of being able to pattern the substrate without performing a subsequent process for removing the residual layer because the residual layer is not left on the transferred pattern.

1 is a schematic view of a patterning method of the present invention.
FIG. 2 is a photograph of a silicon wafer after an inverse imprint process is performed using a duplicate mold in the form of a film [(a): 150 nm hole type, (b): 150 nm L / S
FIG. 3 is an electron micrograph of a UV curable resin pattern formed on a silicon substrate after an inverse imprint process is performed using a 150 nm pillar type mold. [(A): UV curable resin pattern surface, (b) Slant section of resin pattern]
FIG. 4 is an electron micrograph of a UV curable resin pattern formed on a silicon substrate after an inverse imprint process using a 150 nm L / S type mold. [Fig. 4 (a) Section of the UV curable resin pattern]
FIG. 5 is an electron micrograph of a metal nanoparticle array formed on a silicon substrate after depositing gold and removing a cured resin after an inverse imprint process using a 150 nm pillar type mold. FIG.

The present invention

(a) mixing a resin for a replica mold with a photoinitiator to prepare a mold composition;

(b) applying a mold composition of step (a) to a master mold, covering the mold with a substrate, and irradiating / curing ultraviolet rays to prepare a replica mold;

(c) applying a resin for imprinting to the replica mold manufactured in step (b), contacting / pressing the imprint resin to the second substrate, and then curing the patterned resin on the second substrate by applying ultraviolet rays or heat;

(d) releasing the duplicate mold from the second substrate on which the pattern has been transferred;

(e) forming a pattern by applying a second material on the second substrate using the imprinted resin pattern transferred on the second substrate in the step (d); And

(f) removing the imprinting resin on the second substrate by treating the resin etching solution for imprinting; And a patterning method.

Hereinafter, the present invention will be described in detail.

The step (a) is a step of preparing a mold composition, which is prepared by mixing a resin for a replica mold and a photoinitiator.

The resin for the replica mold is preferably one of an acrylic resin, an epoxy resin, a urethane acrylate resin or a UV-curable resin, more preferably a urethane acrylate resin.

The step (b) is a step of preparing a replica mold. The mold composition prepared in the step (a) is applied to a master mold, covered with a substrate, and irradiated with ultraviolet rays.

The substrate is preferably glass, ceramic, plastic or polycarbonate (PC) film, more preferably a transparent film such as polycarbonate.

The master (original) mold is preferably any one selected from the group consisting of a metal plate, a glass plate, a plastic plate, a silicon wafer, a metal oxide wafer and a plastic film.

The fabrication of the master mold can be accomplished by a variety of techniques, including photolithography, electron beam lithography, ion beam lithography, light projection lithography, extreme ultraviolet lithography, x-ray lithography, holographic lithography (laser interference lithography), imprint lithography It is preferable to use one method selected from the group consisting of electroplating.

The pressing in step (b) is preferably performed at 1 to 5 bar, and the ultraviolet irradiation is performed for 2 to 4 minutes.

The step (c) is a step of transferring the pattern of the replica mold to the second substrate, wherein the replica mold is coated with the imprint resin and pressed, and then cured by applying ultraviolet rays or heat.

The imprinting resin is preferably one selected from the group consisting of an ultraviolet (UV) curable resin, a thermoplastic resin and a thermosetting resin.

The pressing is preferably performed at 3 to 10 bar, and the ultraviolet irradiation is preferably performed for 2 to 4 minutes.

The heating temperature depends on the softening point of the thermoplastic imprint resin to be used, and it is generally preferable to heat the glass transition temperature (T _g ) to 50 ° C or more.

The imprinting resin is preferably applied by one method selected from the group consisting of spin coating, dip coating and blade coating.

When the resin for imprinting is applied, it is preferable to use a resin for imprinting with a low viscosity, which is for the formation of a pattern having no residual layer.

Preferably, the second substrate is selected from the group consisting of a metal plate, a silicon wafer, a glass plate, a ceramic plate, a plastic plate, a planar plate shape, a flat surface without bending, and a flexible film.

The pressurization is preferably carried out by using a roller or by using the pressures of air and liquid.

The curing is preferably carried out by one of the methods selected from the group consisting of UV curing, thermosetting, and curing by cooling after heating / molding.

The step (d) is a step of releasing the duplicate mold from the second substrate on which the pattern has been transferred.

The duplicate mold and the substrate are released to form a resin pattern for imprinting on the second substrate.

The step (e) may further include the step of transferring metal and other materials onto the second substrate on which the resin pattern for imprinting is formed, and the second material is deposited on the second substrate formed in the step (d).

Preferably, the second material is selected from the group consisting of metals, oxides, semiconductors, polymeric materials, and organic materials, and can be produced in the form of a film having a thickness in the range of 1 nm to 500 μm.

The pattern formation of the second material is preferably performed by a vacuum deposition method.

At the time of forming the second material pattern, it is preferable to apply the second material directly on the patterned second substrate in step (d), and then remove the imprint resin.

Further, at the time of forming the second material pattern, the time of applying the second material onto the second substrate is performed before contacting / pressing the replica mold having the resin for imprinting applied thereto to the second substrate, The second material applied to the lowermost part on the substrate can be etched.

Etching of the second material may be performed by wet etching using an acid, a base, or an organic solvent; Or ion milling, RIE (reactive ion etching), or ICP (inductively coupled plasma) dry etching.

The second material may be applied by dip coating, spin coating, blade coating, sputtering, E-beam evaporation, thermal evaporation, plasma enhanced chemical vapor deposition (PECVD) , And a low pressure chemical vapor deposition (LPCVD) method.

In the general imprint lithography method, since there is a residual layer in the imprint resin pattern, an oxygen plasma dry etching process for introducing a sacrificial layer or a sacrificial layer for protection of a resin pattern shape for imprinting and for removing a residual layer is indispensably required, In the patterning method of the present invention, there is an effect that the metal deposition can be performed immediately without adding such a process.

The step (f) is a step of removing the imprinting resin on the second substrate after the deposition step (e), and the second substrate is treated with a resin etching solution for imprinting.

The resin etching solution for imprinting may be tetramethyl ammonium hydroxide if it is a UV curable resin; In the case of a thermoplastic resin, an organic solvent is preferred.

Removal of the imprinted resin may be performed by dry etching such as oxygen plasma; Or wet etching using an acid, a base and an organic solvent.

The imprinting resin on the second substrate may be removed through the step (f) to obtain a final metal pattern.

In addition, the processes of steps (a) to (f) may be repeated to form two or more patterns in multiple layers.

The size of the pattern realized by the patterning method ranges from 10 nm to 1 mm.

When the patterning is performed on the substrate by the above patterning method, the fine patterning process can be performed simply and effectively, and a patterning process can be performed on the substrate without performing a subsequent process for removing the residual layer, can do.

A schematic diagram of a patterning method according to the present invention is shown in FIG.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided to facilitate understanding of the present invention, and the present invention is not limited by the examples.

≪ Example 1 > Preparation of reverse imprint mold

1. Preparation of reverse imprint mold composition

An urethane acrylate (MD700) resin and a photoinitiator (Igacure 184) were mixed at a mixing ratio of 98: 2 to prepare an inverse imprint mold composition.

2. Manufacturing of mold for reverse imprint

2 ml of the composition for a mold (resin) prepared in the above 1. was applied to a master silicone stamp (150 nm hole type, 150 nm L / S line type) (25 ° C.) at a pressure of about 1 to 2 bar, and irradiated with ultraviolet rays (UV) for 3 minutes to cure the ultraviolet ray curable resin as a mold composition to prepare a film mold.

<Example 2> An inverse imprint process and a metal thin film deposition

1. Reverse imprint process

A low viscosity UV imprint resin (0.2 ml of NIPSC28LV400 and 2.3 ml of chloroform) was applied by spin coating to the duplicate mold for imprint (150 nm pillar type mold, 150 nm L / S type mold) prepared in Example 1 , Irradiated with ultraviolet rays for 3 minutes while being contacted with a silicon substrate and pressurized at room temperature (25 ° C) at 5 bar, and a patterned silicone substrate and a copying film mold (PC film) were released to form a UV curable resin Pattern was formed. Electron micrographs of UV curable resin patterns formed using a 150 nm pillar type mold and a 150 nm L / S type mold are shown in FIGS. 3 and 4, respectively.

The hole and line pattern of the UV curable resin are effectively formed on the silicon substrate as shown in Figs. 3 (a) and 4 (a), and as shown in Fig. 3 (b) and Fig. 4 (b) It can be confirmed that the residual layer of the cured resin does not exist on the silicon substrate.

2. Deposition of metal thin films

A gold thin film was deposited by an electron beam evaporation method (thickness: 20 nm) in order to further transfer the metal pattern onto the silicon substrate by using the pattern of the residue-free layer UV curable resin as a result of the above-mentioned printing. After the deposition process, the UV curable resin on the silicon substrate was removed by treatment with an alkaline solution (tetramethyl ammonium hydroxide) at 100 ° C or higher for 1 to 3 hours to obtain a final gold nanoparticle array pattern. The size of the obtained pattern is within a range of 10 nm to 1 mm. An electron micrograph of the obtained gold nanoparticle array pattern is shown in FIG.

As shown in FIG. 5, since the remnant layer exists in the pattern of the UV curable resin in the general imprint lithography method, the oxygen plasma dry etching process for the inclined deposition or the sacrificial layer introduction for protecting the curable resin pattern shape and the removal of the residual layer is performed But it is confirmed that metal deposition can be performed without such a process in the present invention.

1: film
2: Mold
3: Resin for imprint
4: substrate
5: Deposition material

Claims (19)

(a) mixing a resin for a replica mold with a photoinitiator to prepare a mold composition;
(b) applying a mold composition of step (a) to a master mold, covering the mold with a substrate, and irradiating / curing ultraviolet rays to prepare a replica mold;
(c) applying a resin for imprinting to the replica mold manufactured in step (b), contacting / pressing the imprint resin to the second substrate, and then curing the patterned resin on the second substrate by applying ultraviolet rays or heat;
(d) releasing the duplicate mold from the second substrate to which the patterned resin has been transferred;
(e) forming a pattern of a second material by applying a second material on the second substrate, on which the resin patterned in step (d) has been transferred, and then removing the imprint resin; And
(f) removing the imprinting resin on the second substrate by treating the resin etching solution for imprinting; / RTI &gt; The patterning method according to claim 1, wherein the resin for the replica mold in step (a) is any one of an acrylic resin, an epoxy resin, a urethane acrylate resin, and a UV curable resin. The method of claim 1, wherein the substrate of step (b) is glass, ceramic, plastic, or polycarbonate (PC). The patterning method according to claim 1, wherein the master mold of step (b) is one selected from the group consisting of a metal plate, a glass plate, a plastic plate, a silicon wafer, a metal oxide wafer and a plastic film. 2. The method of claim 1, wherein the master mold manufacturing method of step (b) comprises the steps of: preparing a master mold by using at least one selected from the group consisting of photolithography, electron beam lithography, ion beam lithography, light projection lithography, extreme ultraviolet lithography, x-ray lithography, holographic lithography Lithography (thermal and UV), injection molding, and electroplating. The patterning method according to claim 1, wherein the imprinting resin in step (c) is at least one selected from the group consisting of ultraviolet (UV) curable resin, thermoplastic resin and thermosetting resin. The method according to claim 1, wherein the imprinting resin in step (c) is applied in one method selected from the group consisting of spin coating, dip coating and blade coating. The patterning method according to claim 1, wherein the imprinting resin of step (c) uses a resin for imprinting at a low viscosity. The method of claim 1, wherein the second substrate is a metal, silicon wafer, glass, ceramic, or plastic material. The second substrate may be a flat plate, a flat surface, Wherein the pattern is a selected one. 2. The method of claim 1, wherein the pressing of step (c) comprises using a roller; Or pressure of air and liquid. The method of claim 1, wherein the curing method of step (c) comprises UV curing; Thermal curing; And curing by heating / cooling after molding. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; The method of claim 1, wherein the second material of step (e) is selected from the group consisting of metals, oxides, semiconductors, polymer materials, and organic materials, . &Lt; / RTI &gt; delete (a) mixing a resin for a replica mold with a photoinitiator to prepare a mold composition;
(b) applying a mold composition of step (a) to a master mold, covering the mold with a substrate, and irradiating / curing ultraviolet rays to prepare a replica mold;
(c) applying the imprinting resin to the replica mold produced in step (b), contacting / pressing the second substrate coated with the second material, applying ultraviolet rays or heat to the patterned resin, Curing step;
(d) releasing the duplicate mold from the second substrate to which the patterned resin has been transferred;
(e) etching the second material applied to the lowermost portion of the patterned resin on the transferred second substrate to form a pattern of the second material; And
(f) removing the imprinting resin on the second substrate by treating the resin etching solution for imprinting; / RTI &gt; 15. The method of claim 14, wherein etching the second material comprises: wet etching using an acid, a base, and an organic solvent; Or dry etching of ion milling, reactive ion etching (RIE), or inductively coupled plasma (ICP). The method of claim 1 or 14, wherein the application of the second material is performed by a method selected from the group consisting of dip coating, spin coating, blade coating, sputtering, E-beam evaporation, thermal evaporation, Characterized in that the method is performed by one of the methods selected from the group consisting of plasma enhanced chemical vapor deposition (PECVD) and low pressure chemical vapor deposition (LPCVD). The method according to claim 1, wherein the removal of the imprint resin in step (f) comprises: dry etching of oxygen plasma; Or a wet etching method using an acid, a base and an organic solvent. The patterning method according to claim 1, wherein the steps (a) to (f) are repeated to form two or more patterns in multiple layers. The method of claim 1, wherein the pattern size implemented by the patterning method is in the range of 10 nm to 1 mm.

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