KR20060089838A - Donor film for thin film transfer - Google Patents

Abstract

The present invention relates to a donor film for a thin film transfer comprising a polymer film layer having a glass transition temperature of room temperature or less, the donor film does not necessarily require a light-heat conversion layer, both metal and organic materials can be transferred, It is efficient because you can transfer multiple layers at once.

Donor Film, PDMS, Patterning

Description

Donor film for thin film transfer

1 is a schematic cross-sectional view showing the structure of a thin film transfer donor film used in a conventional laser transfer method.

Figure 2 is a schematic cross-sectional view showing the structure of the embodiments of the thin film transfer donor film according to the present invention.

3 is a view schematically showing a transfer process using a thin film transfer donor film according to the present invention, Figure 3a is a case where the polymer film layer is flat, Figure 3b is a case where the polymer film layer is patterned.

4 is a view schematically showing a transfer process by a conventional laser transfer method.

* Explanation of symbols for the main parts of the drawings

100, 200, 300: transparent substrate 201, 301: polymer film layer

102, 202, 302, 402: transfer layer 103, 403: photothermal conversion layer

105: intermediate layer 304, 404: acceptor film

The present invention relates to a donor film for thin film transfer, and more particularly, to a donor film for thin film transfer including a polymer film layer having a glass transition temperature of room temperature or less.

The black matrix of the liquid crystal display, the color filter, or the organic layer of the organic light emitting display device, the second electrode of the passive matrix organic light emitting display device, the organic semiconductor of the OTFT, the organic material of the organic solar cell, and the like are generally patterned. .

Recently, the interest in the flexible display (flexible display) is increasing, it is required to make the display unit and the drive unit of the existing display core components consisting of the display unit, the drive unit to have flexibility. The display part needs to replace the glass substrate with plastic, and the driving part with OTFT which replaces TFT using inorganic material with organic semiconductor, and forms TFT at high temperature of 300-400 ℃ by amorphous method, which is an implementation method of conventional TFT-LCT. In order to solve the disadvantage of melting the plastic substrate, there is a need for a method of patterning a flexible OTFT at a lower temperature.

One of the patterned printing methods is an inkjet recording method, and in the case of forming a black matrix by a photoresist method from a black photosensitive resin composition or a photosensitive resin composition in which black pigments, dyes or metal powders are dispersed, application of the resin composition It is essential to carry out various treatments such as curing, exposure, development and drying, and not only the work is complicated, but also the complexity of the processing apparatus and the increase of manufacturing cost must be taken. In addition, even when the black matrix is formed by using a metal thin film, for example, chromium or chromium oxide, instead of the photosensitive resin composition, the photoresist method must be used for patterning the metal thin film.

An organic electroluminescent device is a self-luminous device using a phenomenon in which an electron and a hole combine in an organic layer to generate light when a current flows through a fluorescent or phosphorescent organic layer. The organic light emitting device is light, simple in components, and simple in manufacturing. High quality and wide viewing angle can be realized. In addition, video can be fully realized, high color purity can be realized, and low power consumption and low voltage driving make it suitable for portable electronic devices. The use of the organic light emitting device is very versatile such as a display or a backlight unit.

In general, an organic light emitting display device includes an anode and a cathode, and various layers including a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer.

For full colorization of the organic light emitting device, it is necessary to form a fine pattern of an organic thin film such as a light emitting layer, an electron injection layer, a hole injection layer.

As a method of forming a fine pattern of an organic thin film, there is a lithography method of fine processing an organic thin film by using a photoresist pattern obtained by coating, exposing and developing a photoresist on an organic thin film. However, since the organic thin film formed by this method is deformed by the organic solvent, developer residue, etc. used in the process, practical application is almost impossible. Another method is a vacuum deposition method using a mask, but this has a problem that it is difficult to finely process a few tens of microns.

On the other hand, the method of patterning by the laser transfer method is also known. The color filter layer is formed by a laser transfer method. The color filter layer formed by the color filter layer, the light-to-heat conversion layer and the support film, and a light source such as a laser are irradiated to transfer the color filter layer on the color filter transfer film onto a substrate to produce a color filter layer. How to form. The color filter transfer film is composed of three layers, the lower layer is formed of a support film made of a material having excellent light transmittance, a light-heat conversion layer for converting light energy into thermal energy, and a color filter layer which is a transfer layer. The support film may be formed of a polymer film such as polyester or polyethylene, which is a colorless and transparent material to support the color filter layer and the light-heat conversion layer as well as to allow the laser light to pass through the light-heat conversion layer.

Since the photothermal conversion layer needs to convert light incident through a laser into thermal energy, materials having high thermal conversion capability, for example, organic compounds such as carbon black and IR-pigment, metal materials such as aluminum, oxides of the metal materials, or It consists of a mixture of materials.

The color filter layer is made of a material layer to be transferred, and is made of a material having colors of red, green, and blue.

In order to use the laser transfer method, at least a light source, a transfer film, and a substrate are required, and light emitted from the light source is absorbed by the light absorbing layer of the transfer film and converted into thermal energy, thereby transferring the transfer layer forming material of the transfer film. Transferred to the substrate to form the desired image.

U.S. Patent No. 2004-0191564 includes a base film, a photothermal conversion layer formed on the base film, and a transfer layer formed on the photothermal conversion layer and made of a low molecular material, the transfer layer being heated by a laser. Part of the transfer layer irradiated with the laser is irradiated with the laser and the transfer layer is separated by the change of the adhesive force with the photothermal conversion layer, and the portion not irradiated by the laser is fixed to the photothermal conversion layer by the adhesive force. The adhesion between the substrate and the low molecular material of the organic light emitting device to which the low molecular material formed on the substrate is transferred, and the adhesion between the photothermal conversion layer and the low molecular material are reduced to the low molecular material and the laser in the region irradiated with the laser. The low molecular weight material in the irradiated area is greater than the adhesion between the low molecular weight material in the unirradiated area And a low molecular material in a region not irradiated with a laser is separated from each other to disclose a donor film for a low molecular full color organic electroluminescent device, characterized in that a material transition occurs from the photothermal conversion layer to a substrate.

Korean Patent No. 10-0195175 discloses a donor film for an organic electroluminescent device organic thin film comprising a base film, a photothermal conversion layer formed on the base film, and a transfer layer formed on the photothermal conversion layer. And at least one material selected from the group consisting of a light emitting body selected from an organic electroluminescent material, an organometallic complex electroluminescent material, and an electroluminescent polymer, a hole injection low molecule, a hole injection polymer, an electron injection low molecule and an electron injection polymer. The donor film for organic electroluminescent element organic thin films which consists of this is disclosed.

However, when the pattern is transferred in this manner, the flexibility of the upper donor film is lowered, and thus the adhesive force with the lower acceptor film is low, which requires a lot of heat during the transfer. In addition, since only organic material transfer is possible, there is a need to separately perform a step of depositing a metal after patterning the organic layer. In addition, a photothermal conversion layer is necessarily required.

Meanwhile, polydimethylsiloxane (PDMS) is a kind of silicone-based rubber having a low glass transition temperature and a patterning method using the same as a mold is known.

Korean Patent Publication No. 10-2004-0098965 includes the steps of defining a plurality of first, second and third color pixels representing a first color, a second color and a third color on a substrate; Attaching a first mold having a pattern corresponding to the first color pixel on the substrate, and filling the pattern with a first color resin to form a first color filter pattern; Attaching a second mold having a pattern corresponding to the first and second color pixels on the substrate, and filling the pattern with a second color resin to form a second color filter pattern; Attaching a third mold having a pattern corresponding to the plurality of first, second, and third color pixels on the substrate, and filling the pattern with a third color resin to form a third color filter pattern; A color filter manufacturing method is disclosed, which is a method of patterning a color filter by soft lithography.

In addition, Korean Patent Laid-Open Publication No. 2003-0073578 discloses a passive matrix type organic electroluminescent device having a light emitting region in which portions of first and second electrodes intersecting an organic electroluminescent layer intersect as a light emitting region, the first being formed on a substrate in a first direction. An electrode; An organic light emitting layer formed on the entire surface of the substrate covering the first electrode; Located in the upper portion of the organic electroluminescent layer, located in a second direction intersecting with the first direction, the concave and convex portions in which the relationship of W / L = 0.2-20 and D≥L x 20 is established repeatedly A passive matrix organic electroluminescent device comprising a second electrode formed by a thermal transfer method by a PDMS mold having a portion is disclosed. In the method, the patterned second electrode is formed by bonding the mold to the second electrode, followed by thermosetting to remove the second electrode adhering to the convex portion of the mold from the substrate. That is, in the method, the PDMS mold is attached to the second electrode deposited on the front surface, and heat is applied to remove the metal from the PDMS mold in a state in which the adhesion between the metal and the PDMS is increased, that is, the metal is lift-off. There is a limitation that only patterning is possible.

Therefore, the technical problem to be achieved by the present invention is good adhesion between the transfer layer of the donor film and the acceptor film to be transferred is possible with a low energy, can transfer several layers at once, and does not require a photothermal conversion layer The present invention provides a donor film for thin film transfer that can also transfer layers other than metal.

In order to achieve the above technical problem, in the present invention

A polymer film layer having a glass transition temperature of room temperature or less; And a transfer layer attached to the polymer film layer.

According to the exemplary embodiment of the present invention, the polymer film layer may be patterned in a concave-convex shape on the side to which the transfer layer is attached.

According to another embodiment of the present invention, the donor film may further include a transparent substrate on the polymer film layer on the opposite side to the transfer layer is attached.

According to another embodiment of the present invention, the transparent substrate is glass, polyethylene terephthalate, polycarbonate, polyester, polyethylene naphthalate, polyestersulfonate, polysulfonate, polyarylate, fluorinated polyimide, fluorinated resin , Polyacryl, polyepoxy, polyethylene, polystyrene, polyacetate, and polyimide.

According to another embodiment of the present invention the polymer film layer is a transparent silicone-based elastomer, polybutadiene (Polybutadiene), nitrile rubber (Nitrile rubber), acrylic rubber (butyl rubber), butyl rubber (Polyisoprene) and It may be at least one selected from the group consisting of polystyrene-butadiene copolymer (Poly (Styrene-co-Butadiene).

According to another embodiment of the present invention, the transfer layer may be a metal, a low molecular organic material or a high molecular organic material, or a metal or a low molecular organic material, or a single layer or a multilayer consisting of a metal and a high molecular organic material.

The donor film for thin film transfer according to the present invention does not necessarily have to include a photothermal conversion layer, can transfer several layers at the same time, and can be transferred with a small amount of energy.

Hereinafter, the present invention will be described in detail with reference to the drawings.

The thin film transfer donor film according to the present invention comprises a polymer film layer having a glass transition temperature of room temperature or less; And a transfer layer attached to the polymer film layer, wherein the donor film may further include a transparent substrate on the polymer film layer on the opposite side to the surface on which the transfer layer is attached.

The transparent substrate may be glass, polyethylene terephthalate, polycarbonate, polyester, polyethylene naphthalate, polyestersulfonate, polysulfonate, polyarylate, fluorinated polyimide, fluorinated resin, polyacryl, polyepoxy, It may be any one selected from the group consisting of polyethylene, polystyrene, polyacetate and polyimide. The transparent substrate is generally 10 to 500 mu m in thickness.

The transparent substrate is intended to provide some support to the donor film because the polymer film layer is flexible. It is particularly preferable when the organic material is to be transferred.

The polymer film layer having a glass transition temperature of less than or equal to room temperature may have a surface to which the transfer layer is attached is patterned in an uneven form. As the upper substrate is provided such that the concave portion and the convex portion exist, when applying energy such as light and heat to the donor film, patterning is possible even when irradiating light as a whole without scanning and applying as in the conventional laser transfer method. There is an advantage. Therefore, a large number of transfers are possible in a single process.

The soft polymer film layer having a glass transition temperature of less than or equal to room temperature may include a transparent silicone-based elastomer, polybutadiene, nitrile rubber, acrylic rubber, butyl rubber, polyisoprene, and It may be one or more selected from the group consisting of polystyrene-butadiene copolymers (Poly (Styrene-co-Butadiene)), and most preferably polydimethylsiloxane.

Since the polymer constituting the polymer film layer has a glass transition temperature of less than or equal to room temperature, a conformal contact is possible when contacting the organic layer below, and van der Waals attraction between molecules and atoms (Van) occurs. Because of the strong der Waals interaction, the transfer between the polymer film layer and the organic layer, which is the transfer layer, can be easily performed even without applying much heat or light .

The donor film for thin film transfer according to the present invention may transfer the transfer layer from the polymer film layer to the acceptor film by applying light, heat, pressure or electricity.

If the energy source is light, the polymer film layer can be irradiated by scanning with an IR laser when the flat pattern is unpatterned, and when the polymer film layer is patterned, the laser can be exposed to the front surface (flood exposure). It is more preferable at the point which can transfer a large amount by operation. Alternatively, when the energy source is light, it is possible to perform full exposure at once with an ultraviolet lamp, so that a large amount of transfer can be performed by a much simpler operation. The irradiation time of the irradiated light may be adjusted according to the intensity of the lamp. For example, if the intensity is 10 mW / cm ² can be treated for 5-10 minutes. If it is necessary to transfer the infrared lamps in a short time at a time, a photothermal conversion layer may be selectively inserted.

If the energy source is heat, transfer is possible by treatment at a temperature of 60 to 80 ^° C. for 10 to 30 minutes.

When the energy source is pressure, it is desirable to further form a glass support layer on the opposite side of the patterned side of the patterned soft polymer film layer so that a uniform pressure is applied throughout the donor film. The pressure can be applied for 2 to 60 seconds in the size of 10 kPa to 100 mPa.

When electricity is used as the energy source, the applied electricity can flow for 1 minute to 1 hour in the size of 1 mA / cm ² to 10 A / cm ² .

By using the polymer film layer having a low glass transition temperature, it is not necessary to necessarily use the light-to-heat conversion layer used in the conventional laser induced thermal imaging (LITI). However, when light is used as an energy source, a light-to-heat conversion layer may be further included in order to efficiently transfer the light.

The photothermal conversion layer may be formed of a light absorbing material having a property of absorbing light in the infrared-visible light region. Examples of the film having such characteristics include a metal film made of aluminum, its oxides and sulfides, and an organic film made of a polymer to which carbon black, graphite or infrared dye is added. At this time, the metal film may be coated with a thickness of 100 to 5000 kPa using a vacuum deposition method, an electron beam deposition method or sputtering.

In addition, as described above, when the light-heat conversion layer is further included, an intermediate layer may be further included between the light-heat conversion layer and the transfer layer to facilitate separation of the light-heat conversion layer and the transfer layer. The intermediate layer may be made of any one selected from the group consisting of thermosetting polymers or thermoplastic polymers, crosslinkable polyacrylates, polymethacrylates, polyesters, epoxides and polyurethanes.

The transfer layer may be a metal, a low molecular organic material, or a high molecular organic material, or a single layer or a multilayer of a metal and a low molecular organic material, or a metal and a high molecular organic material.

When the transfer layer is made of a metal, the metal may be a metal having a work function of 2.0 eV to 6.0 eV, or may be a two-layer structure of a first metal layer and a second metal layer. In the case of such a two-layer structure, the first metal layer attached to the polymer film layer may have a high work function, and may not react well with the polymer film layer. Examples include Al, Ag, Au, Pd, or Pt. The second metal layer attached to the first metal layer is preferably a metal having a low work function, and examples thereof include Ba, Ca, Mg, Cs or Li, and alloys thereof or with other metals.

When the transfer layer is made of a low molecular organic material or a high molecular organic material, the low molecular or high molecular organic material may have semiconductor properties or have electroluminescent properties according to the specific type of the device to be transferred.

For example, when the object to be transferred is an organic layer of the organic light emitting device, the transfer layer may be a light emitting layer having a band gap of 1.0 eV to 7.0 eV, or a single layer of an electron transport layer or an organic material forming a multilayer of an electron transport layer / light emitting layer.

In the donor film for thin film transfer according to the present invention, the transfer layer is transferred from the polymer film layer to the acceptor film by heat, light, electricity or pressure. When the transfer layer is an organic material layer or an organic material layer including a metal layer, adhesion between the organic material and the organic material forming the acceptor film may be increased by heat, light, or pressure so that the transfer layer may be easily separated from the polymer film layer. In addition, when the transfer layer is a metal layer, the adhesion between the metal and the organic material forming the acceptor film is greater than the adhesion between the metal and the polymer film layer, so that the transfer layer is easily separated from the polymer film layer even with a little energy. Can be.

That is, when PDMS is used as the soft polymer film, the difference in adhesion force (W) can be expressed as surface energy (γ) as follows.

W _(3-2) = γ ₃ + γ ₂ -γ ₃₂

W _(1-2) = γ ₁ + γ ₂ -γ ₁₂

Because of

W _(3-2) -W _(1-2) = (γ ₃ -γ ₁ ) -(γ ₃₂ -γ ₁₂ )

When 1 is a soft polymer film, 2 is a metal, and 3 is a lower organic layer, the second term is much smaller than the first term. Because γ _(metal) This is because γ _{(suborganism )} or γ _(PDMS) is much larger. Therefore, the difference in the surface energy of the lower organic layer and the PDMS is equal to the difference in adhesion. In the case of PDMS, the surface energy is very low, 19.8 mJ / m ^2, and thus has a weaker binding force than the lower organic layer. When the lower organic layer is MEH-PPV [poly (2-methoxy-5- (2'-ethyl-hexyloxy) -1,4-phenylenevinylene)] as a light emitting material, it exhibits 28.0 mJ / m ² . Even if there is no external energy, if you put it on for a long time, the transfer occurs well due to the difference in bonding force. If the external energy, that is, heat is applied at 80 ^o C for more than 20 minutes, the transfer takes place faster.

After the transfer process, an optional heat treatment process is required to fix the transferred material.

1 is a schematic cross-sectional view of a thin film transfer donor film used in a conventional laser transfer method, Figure 2 is a schematic cross-sectional view showing embodiments of a thin film transfer donor film according to the present invention. As shown in FIG. 1, the donor film used in the conventional laser transfer method has a form in which the photothermal conversion layer 103 and the transfer layer 102 are sequentially stacked on the substrate 100 (FIG. 1A), or the photothermal conversion It may further include an intermediate layer 105 to facilitate separation between the two layers between the layer 103 and the transfer layer 102 (FIG. 1B).

In contrast, the thin film transfer donor film according to the present invention has a structure as shown in Figs. 2a to 2f, wherein Figs. 2a to 2d have a flat polymer film layer 201, Figs. 2e and 2F is a pattern in which the soft polymer film layer is patterned. In the thin film transfer donor film according to the present invention, the transfer film 202 is deposited on the polymer film layer 201 (FIG. 2A), or the polymer film layer 201 is attached to the transparent substrate 200. The transfer layer 202 may have a structure (FIG. 2B to FIG. 2F) attached thereto, and the transfer layer 202 may be formed of metal layers 202a, 202a ′, 202a ″ or a metal layer and an organic material layer 202b. When the metal layer has a two-layer structure, the first metal layer 202a ′ attached to the polymer film layer 201 is a metal layer having low reactivity, and the second metal layer 202 a ″ attached on the first metal layer is a highly reactive metal layer. Can be. For example, when forming an organic light emitting device, the first metal layer may be Al, Ag, Au, Pd or Pt, and the second metal layer may be Ba, Ca, Mg, Cs, Li, or an alloy thereof. The work function may be a low metal, and the organic material layer may be an electron transport layer or a light emitting layer.

The thin film transfer donor film according to the present invention comprises the steps of preparing a polymer film layer having a glass transition temperature of less than room temperature; And it may be prepared by a method comprising the step of depositing a transfer layer on the polymer film layer.

When the polymer film layer is attached to the transparent substrate, the method may further include attaching the polymer film layer to the transparent substrate before depositing a transfer layer on the polymer film layer.

The polymer film layer may be formed by using a flat master or having a concave-convex pattern according to a flat case or a patterned case. For example, the patterned polymer film layer is described below. A master made of a wafer or the like is prepared. The master has a predetermined uneven pattern. Then, a precursor solution for polymer film formation is prepared. The polymer film forming solution is easily available from various chemical companies. For example, if you want to obtain polydimethylsiloxane (PDMS), you can use Sylgard 184 series from Dow Chemical Inc. Can be. The prepared polymer film-forming solution is poured into a master, and then the solution is conditioned at an appropriate temperature (for example, PDMS for 30 minutes to 24 hours at room temperature to 100 ° C, preferably for 1 to 3 hours at 60 ° C to 80 ° C. ) To form a patterned polymer film layer. The patterned polymer film layer is removed from the master.

The opposite flat side of the patterned polymer film layer prepared as above is attached to a transparent substrate. Then, the transfer layer is entirely deposited on the polymer film layer opposite to the surface attached to the transparent substrate. In this case, in the case of the patterned polymer film layer, vertical deposition is used to prevent deposition on the side surface. There is no particular limitation on the deposition process, and various deposition methods such as sputtering, e-beam deposition, thermal deposition, and the like may be used.

Before the deposition of the transfer layer on the polymer film layer may be formed a light-heat conversion layer. The photothermal conversion layer is formed of a light absorbing material having a property of absorbing light in the infrared-visible light region. As the film having such characteristics, there is a metal film made of aluminum, its oxide and sulfide, and an organic film made of a polymer to which carbon black, graphite or infrared dye is added. In this case, the metal film is formed to a thickness of 10 to 500 nm by thermal evaporation, electron beam evaporation, or sputtering, and in the case of an organic film, an extrusion, spin, and knife coating method, which is a general film coating method, is used. To form a thickness of 0.1 to 10μm.

When the photothermal conversion layer is formed as described above, an intermediate layer may be formed after the photothermal conversion layer is formed and before the transfer layer is deposited. The intermediate layer serves to protect the photothermal conversion layer and to minimize contamination or damage that may occur on the portion transferred from the transfer layer. This intermediate layer has a very high thermal stability so that it does not deteriorate due to deformation or chemical decomposition by external energy. This intermediate layer is attached to the transfer layer but is not transferred together when transferred. Suitable intermediate layers may be polymer films, metal layers, inorganic layers, organic / inorganic composite layers. Suitable materials for the use of organics as interlayers include both thermosets and thermoplastics. Suitable thermosetting materials are crosslinked by heat, light, chemical treatment, and the like, which may be mainly crosslinked polyacrylates, polymethacrylates, polyesters, epoxies and polyurethanes. The thermosetting material is crosslinked after the coating on the photothermal conversion layer in the precursor state. Suitable thermoplastics on the other hand may be polyacrylates, polymethacrylates, polystyrenes, polyurethanes, polysulfones, polyesters and polyimides. Thermoplastic organics can be prepared through traditional coating methods such as spin coating and spray coating. The glass transition temperature of the thermoplastic material should be greater than the soft polymer film layer having a glass transition temperature below room temperature and above the room temperature and preferably above 100 ^° C. Materials that can be used as the interlayer can be used by coating metal, metal oxide, metal sufide and inorganic carbon.

The thin film transfer donor film according to the present invention prepared as described above may be transferred in a slightly different method depending on the case where the polymer film layer is patterned and flat.

3 is a view showing a transfer process using a thin film transfer donor film according to the present invention, Figure 3a is a case where the polymer film layer is flat, Figure 3b shows a case where the polymer film layer is patterned.

As shown in FIG. 3A, in the case of the flat polymer film layer, the polymer film layer 301 partially irradiates the surface of the polymer film layer 301 with an energy source such as an IR laser, thereby causing the winkling of the high molecular film layer. Adhesion with the transfer layer 302 deposited on the polymer film layer 301 is reduced so that the transfer layer is transferred onto the film of the acceptor 304.

As shown in FIG. 3B, in the case of the patterned polymer film layer, the convex portion of the donor film is brought into contact with the acceptor film 304, and then the front surface of the polymer film layer 301 is exposed with an energy source such as an IR lamp. flood exposure), due to the difference in adhesion between the polymer film layer 301 and the transfer layer 302 and the adhesion between the transfer layer 302 and the acceptor film 304, 302 is transferred to acceptor film 301.

For comparison, FIG. 4 shows a transfer process by a conventional laser transfer method. When the laser is partially irradiated to the photothermal conversion layer 403, a portion of the transfer layer 402 attached to the photothermal conversion layer 403 is formed. And transferred to the acceptor film 404. In this case, as in the present invention, the entire exposure (Flood exposure) irradiated to the entire donor film is impossible, the energy applied for the transfer is much more necessary, and the light-heat conversion layer must be included as a disadvantage.

The second electrode, organic layer, or second electrode and organic layer of the organic light emitting display device or the color filter and the black matrix of the liquid crystal display device may be formed using the thin film transfer donor film manufactured as described above. It is possible to pattern organic materials such as switching units of OTFTs and organic solar cells.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example

Example 1

Preparation of Donor Thin Film

Sylgard 184A and Sylgard 184B (manufactured by Dow Corning Inc.) were mixed at a weight ratio of 10: 1 in a stirring vessel. The solution for forming PDMS obtained therefrom was poured onto a master made of a prepared wafer. The master has a stripe pattern. Bubbles in the PDMS forming solution poured on the master were removed using a vacuum pump, and then placed in an oven to cure the PDMS forming solution at 60 ° C. to 80 ° C., and then the master was removed to obtain a PDMS film layer. .

After attaching the PDMS film layer obtained above to a transparent substrate (polyethylene terephthalate, 0.5 mm thick), 20 nm of Au metal was deposited by electron beam on the patterned surface of the PDMS film layer, and 10 nm of Al metal and 5 nm of Ca metal were deposited. After deposition by thermal deposition, 20 nm of alumina quinone (Alq3), which is an electron transport layer material, was sequentially deposited by thermal deposition. The vacuum degree used at this time was ¹ × 10 ^-7 torr.

Fabrication of Patterned Organic Electroluminescent Device

Corning 15Ω / cm ² (1200Å) ITO glass substrates were cut into 50mm x 50mm x 0.7mm and ultrasonically cleaned for 5 minutes in isopropyl alcohol and pure water, followed by UV and ozone cleaning for 30 minutes. . A 10 nm thick hole transport layer was formed by spin coating PFB (hole transport material manufactured by Dow Chemical Co., Ltd.) on the ITO electrode. A 70 nm-thick light emitting layer was formed on the hole transport layer using MEH-PPV light emitting polymer, which is an orange light emitting material. Then, the convex portion of the donor film prepared above was contacted on the light emitting layer and irradiated with an IR lamp for 10 minutes to transfer. The organic electroluminescent element was completed by performing the following.

Example 2

Preparation of Donor Thin Film

Sylgard 184A and Sylgard 184B (manufactured by Dow Corning Inc.) were mixed at a weight ratio of 10: 1 in a stirring vessel. The solution for forming PDMS obtained therefrom was poured onto a master made of a prepared wafer. The master has the shape of the source and drain electrodes of the transistor. Bubbles in the PDMS forming solution poured on the master were removed using a vacuum pump, and then placed in an oven to cure the PDMS forming solution at 60 ° C. to 80 ° C., and then the master was removed to obtain a PDMS film layer.

The PDMS film layer obtained above was attached to a transparent substrate (polyethylene terephthalate, 0.5 mm thick) and 20 nm of Au metal was vertically deposited on the patterned surface of the PDMS film layer by electron beam deposition. The vacuum degree used at this time was ¹ × 10 ^-7 torr.

Fabrication of Organic Thin Film Transistor Devices

As a substrate and a gate electrode, an AlNd metal film deposited at 150 nm on a glass substrate was cut into a size of 1 inch x 1 inch, ultrasonically cleaned in isopropyl alcohol and pure water for 5 minutes, and then UV and ozone cleaned for 30 minutes. It was. After dissolving polyvinylphenol (Aldirch, Mw = 8,000) in a cyclohexanone solvent on the gate electrode and spin coating at 500 nm for 1 hour on a 100 ^° C hot plate, the convex portion of the donor film prepared above After contacting, an IR lamp was exposed to light (50 mJ / cm ² ) for 10 minutes at an intensity of 5 mW / cm ² , followed by transfer, and then pentacene was deposited to a thickness of 60 nm by thermal evaporation to complete the organic thin film transistor element. .

Comparative Example 1

Preparation of Donor Thin Film

Photothermal conversion solution (4% carbon black dye and 0.7% polyvinyl butyral resin, 2.1% acrylic resin, 13% epoxy novolac acrylate) on polyethylene terephthalate (PET) film substrate having a thickness of 0.1 mm A small amount of dispersant (0.3%) and surfactant (0.01%), including 8% acrylic resin, were used as a solvent with 2-butanone and 1,2-propanediol monomethyl ether acetate. The solution used) was spin-coated, dried at a temperature of 80 ^° C., and crosslinked by exposing ultraviolet light. Then, in order to coat the intermediate layer on the photothermal conversion layer, 15% of trimethylpropane triacrylate ester was dissolved in 2-butanone and 1-methoxy-2-propanol co-solvent by adding a small amount of a dispersant, a surfactant, and a crosslinking agent, followed by coating. Dry and crosslink at 60 ^° C. After dissolving MEH-PPV in toluene at 0.6wt%, spin coating was carried out to form a thin film of 70 nm, and alumina quinone (Alq3) was formed by vacuum thermal deposition at 20 nm to complete a donor film.

Fabrication of Patterned Organic Electroluminescent Device

Corning 15Ω / cm ² (1200Å) ITO glass substrates were cut into 50mm x 50mm x 0.7mm and ultrasonically cleaned for 5 minutes in isopropyl alcohol and pure water, followed by UV and ozone cleaning for 30 minutes. . Spin coating a PFB (hole transport material manufactured by Dow Chemical Co., Ltd.) on the ITO electrode to form a hole transport layer having a thickness of 10 nm, and then contacting the donor film prepared above with the hole transport layer and then using a single mode Nd: Yag laser. Scanning was performed. The irradiated laser energy density was 600 mJ / cm ² and the scanning speed was performed at 1 m / s. After the transfer, the heat treatment was performed at 100 ^° C. for 30 minutes, and Ca 5 nm / Al 250 nm was deposited to complete the organic light emitting device.

Evaluation test

The yield (99%) of the pattern obtained in Example 1 was similar to the yield (98%) performed in Comparative Example 1. However, when the luminous efficiency of the device obtained in Example 1 was measured with a Minolta CS-1000 luminance meter and a Keithley 236 current-voltage application-measuring device, it showed 2 cd / A. cd / A is shown.

From this, it can be seen that the luminous efficiency is further increased in the device fabricated by the present invention, which is considered to be due to the remarkably small time and energy to be exposed to light.

The donor film for thin film transfer of the present invention can be easily transferred from the polymer film layer to the acceptor film by light or heat, without having to provide a light-heat conversion layer, and also transfers not only metals but also organic material layers. It is possible.

Claims (16)

A polymer film layer having a glass transition temperature of room temperature or less; And a transfer layer attached to the polymer film layer. The donor film of claim 1, wherein the donor film further comprises a transparent substrate on a polymer film layer on a side opposite to the side on which the transfer layer is attached. The method of claim 2, wherein the transparent substrate is glass, polyethylene terephthalate, polycarbonate, polyester, polyethylene naphthalate, polyester sulfonate, polysulfonate, polyarylate, fluorinated polyimide, fluorinated resin, polyacryl And a polyepoxy, polyethylene, polystyrene, polyacetate and polyimide, any one selected from the group consisting of thin film transfer donor film. The donor film for thin film transfer according to claim 1, wherein the polymer film layer is patterned on the side to which the transfer layer is attached. The method of claim 1, wherein the polymer film layer is a transparent silicone elastomer, polybutadiene (Polybutadiene), nitrile rubber (Nitrile rubber), acrylic rubber (Acryl rubber), butyl rubber (Polyyl rubber), polyisoprene (Polyisoprene), and polystyrene -Butadiene copolymer (Poly (Styrene-co-Butadiene)) is a thin film transfer donor film, characterized in that at least one member selected from the group consisting of. The donor film for thin film transfer according to claim 5, wherein the transparent silicone elastomer is polydimethylsiloxane (PDMS). The donor film for thin film transfer according to claim 1, wherein the transfer layer is a single layer or a multilayer of a metal, a low molecular organic material or a high molecular organic material, or a metal and a low molecular organic material, or a metal and a high molecular organic material. The donor film of claim 7, wherein the low molecular weight or high molecular organic material has a bandgap of 1.0 eV to 7.0 eV. The donor film for thin film transfer according to claim 8, wherein when the transfer layer is formed of a low molecular organic material or a high molecular organic material, a single layer of a light emitting layer or an electron transport layer or a multilayer of an electron transport layer / light emitting layer. The donor film for thin film transfer according to claim 1, further comprising a photothermal conversion layer between the polymer film layer and the transfer layer. The donor film for thin film transfer according to claim 10, further comprising an intermediate layer between the light-to-heat conversion layer and the transfer layer. The thin film transfer method of claim 11, wherein the intermediate layer is any one selected from the group consisting of a thermosetting polymer or a thermoplastic polymer, a crosslinkable polyacrylate, a polymethacrylate, a polyester, an epoxide, and a polyurethane. Donor film. 8. The donor film for thin film transfer according to claim 7, wherein the metal has a work function of 2.0 eV to 6.0 eV. The donor film for thin film transfer according to claim 7, wherein the metal is at least one selected from the group consisting of Al, Ag, Au, Pd, Pt, Ca, Mg, Cs, Li, and Ba. 8. The donor film for thin film transfer according to claim 7, wherein the organic material has semiconductor properties. The donor film for thin film transfer according to claim 7, wherein the organic material has electroluminescent properties.

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