KR100769431B1 - Manufacturing method of donor film and manufacturing method of organic electroluminescent display device using the same - Google Patents

Abstract

The present invention relates to a method of manufacturing a donor film and a method of manufacturing an organic electroluminescent display device using the same in which the transfer layer is formed in the transfer layer forming step of the donor film to improve the deposition rate of the transfer layer. A method of manufacturing a donor film according to the invention includes forming a light-to-heat conversion layer on a base film, and forming a transfer layer on the light-to-heat conversion layer at a deposition rate of 1.1 to 10 kW / s. do. As a result, the adhesion between the transfer layer and the acceptor substrate transferred to the pixel electrode of the acceptor substrate can be improved.

Description

 Method of manufacturing donor film and method of manufacturing organic electroluminescent display device using the same {Method For Donor Film and method for fabricating of the Organic Light Emitting Display of the same}

1A to 1E are cross-sectional views illustrating a method of manufacturing an organic light emitting display device using a donor film according to the prior art.

2 is an atomic force micrograph of the roughness of the surface of the transfer layer according to the prior art.

3 is a cross-sectional view illustrating a method of manufacturing a donor film according to the present invention.

4A and 4B are atomic micrographs measuring the roughness of the surface of the transfer layer according to the present invention.

5A to 5E are cross-sectional views illustrating a method of manufacturing an organic light emitting display device using a donor film according to the present invention.

♣ Explanation of symbols for the main parts of the drawing ♣

 210: acceptor substrate 220: transfer layer

 230: intermediate layer 240: light-heat conversion layer

 250: substrate 260: donor film

The present invention relates to a method of manufacturing a donor film and a method of manufacturing an organic light emitting display device using the same, and more specifically, to form a transfer layer uniformly on the transfer layer deposition rate in the transfer layer forming step of the donor film. The present invention relates to a method of manufacturing a donor film, and a method of manufacturing an organic light emitting display device using the same.

In general, an organic light emitting device has a structure including a pair of electrodes consisting of an anode and a cathode, and a light emitting layer, and more specifically, a hole injection layer and a hole. The transport layer, the electron injection layer and the electron transport layer may be further included.

In such an organic electroluminescent device, in order to realize full colorization, a light emitting layer must be patterned. The method of patterning the light emitting layer includes a shadow mask, inkjet printing, and laser thermal transfer. Among them, the laser thermal transfer method is a dry process, and thus, an organic film may be more finely deposited.

Hereinafter, a method of manufacturing the organic light emitting display device using the laser thermal transfer method according to the prior art will be described in more detail.

1A to 1E are cross-sectional views illustrating a method of manufacturing an organic light emitting display device using a donor film according to the prior art.

Referring to FIG. 1A, in order to manufacture the organic light emitting display device 100 according to the related art, the acceptor substrate 110 is first prepared. The acceptor substrate 110 includes a thin film transistor, a pixel electrode layer electrically connected to the thin film transistor, and a pixel definition layer.

Referring to FIG. 1B, in order to transfer the transfer layer 120 of the donor film 160 to the pixel electrode of the acceptor substrate 110, the donor film 160 is spaced a predetermined distance apart from the upper portion of the acceptor substrate 110. Place it. In this case, the transfer layer 120 of the donor film 160 is disposed to face the acceptor substrate 110 on which the pixel electrode is formed.

At this time, the donor film 160 is the substrate substrate 150, the light-to-heat conversion layer 140 formed on the base substrate 150, the intermediate layer 130 formed on the light-heat conversion layer 140, the intermediate layer ( And a transfer layer 120 formed on the 130.

The base substrate 150 serves as a supporting substrate, and the transparency is made of a polymer material, for example, polyester, polyacryl, polyepoxy, polyethylene, and polystyrene to transmit light to the light-to-heat conversion layer 140. It consists of one or more polymer materials selected from.

The light-to-heat conversion layer 140 is formed on the entire surface of the substrate 150 with a predetermined thickness. The light-to-heat conversion layer 140 absorbs light in the infrared-visible light region and converts a portion of the light into heat. The light-to-heat conversion layer 140 has a suitable optical density and is a light absorbing material for absorbing light. Is formed.

The intermediate layer 130 is formed to have a predetermined thickness on the entire surface of the light-to-heat conversion layer 140. The intermediate layer 130 serves to prevent the light-heat absorbing material from contaminating or damaging the transfer layer 120 formed in a subsequent process and to control the adhesion with the transfer layer 120 to improve transfer pattern characteristics. .

The transfer layer 120 is formed to have a predetermined thickness on the entire surface of the intermediate layer 130. At this time, the transfer layer 120 is formed at a deposition rate of less than 1 Å / s using a method selected from the group consisting of extrusion, spin coating, knife coating, vacuum deposition and CVD (chemical vapor deposition) do.

Referring to FIG. 1C, the donor film 160 is laminated on the acceptor substrate 110. The better the adhesion between the donor film 160 and the acceptor substrate 110, the better the transfer efficiency in the subsequent transfer process. Therefore, laminating the donor film 160 so that the adhesion on the acceptor substrate 110 becomes good. desirable. As the laser is irradiated onto the donor film 160 to absorb the laser light from the light-to-heat conversion layer 140 and convert the laser light into thermal energy to release heat, the adhesion between the transfer layer 120 and the intermediate layer 130 is changed. The transfer layer 120 is separated from the donor film 160.

Referring to FIG. 1D, the transfer layer 120 is transferred onto the pixel electrode of the acceptor substrate 110 to form the emission layer 120b. At this time, the transfer layer 120 is transferred only to the area irradiated with the laser, the transfer layer 120a of the area not irradiated with the laser remains on the donor film 160 as it is.

Referring to FIG. 1E, when the light emitting layer 120b is formed on the pixel electrode of the acceptor substrate 110, the donor film 160 and the acceptor substrate 110 are separated, and then the acceptor substrate on which the light emitting layer 120b is formed ( The counter electrode 170 is formed on the 110.

2 is an atomic force microscope (AFM) photograph of the roughness of the surface of the transfer layer according to the prior art.

Referring to Figure 2, it can be confirmed the roughness of the surface of the transfer layer according to the deposition rate. In particular, looking at "A" representing the surface roughness of the transfer layer, when the deposition rate is 0.3 Å / s, the average value of the transfer layer surface ("A") roughness (RMS) represents 4.4 nm.

As described above, the surface roughness of the region “A” was measured. As the transfer layer formed of the low molecular weight material is deposited at a rate of less than 1 μs / s, the surface roughness of the transfer layer is high and the molecules forming the transfer layer. The cohesion strength between and molecules is low.

As described above, as the roughness of the surface of the transfer layer is high, the contact surface area between the acceptor substrate and the transfer layer is formed wide in the transfer layer transfer step, thereby decreasing the cohesion strength between the transfer layer and the acceptor substrate. . In addition, as the cohesion between the molecules constituting the transfer layer and the injection is low, the transfer layer may be buried or torn off on the acceptor substrate during the transfer phase during transfer of the transfer layer. Accordingly, the transfer layer has a problem that can be detached from the acceptor substrate.

Accordingly, the present invention is an invention derived to solve the above-mentioned conventional problems, and improves the deposition rate of the transfer layer in the transfer layer forming step of the donor film of the donor film that can form a uniform and dense surface of the transfer layer An object of the present invention is to provide a manufacturing method and a method of manufacturing an organic light emitting display device using the same.

According to an aspect of the present invention for achieving the above object, a method of manufacturing a donor film according to the present invention comprises the steps of forming a light-to-heat conversion layer on the base film, 1.1 on the light-to-heat conversion layer Forming a transfer layer at a deposition rate of from 10 μs / s.

Preferably, the transfer layer is formed of a low molecular organic layer, the transfer layer is formed by one of vacuum deposition and CVD, an intermediate layer is further formed between the light-to-heat conversion layer and the transfer layer.

 According to another aspect of the present invention, a method of manufacturing an organic light emitting display device according to the present invention comprises the steps of preparing an acceptor substrate having a pixel electrode, a substrate substrate on the substrate, the optical substrate formed on the substrate- Preparing a donor film including a thermal conversion layer and a transfer layer formed on the light-to-heat conversion layer at a deposition rate of 1.1 to 10 Å / s, wherein the transfer layer of the donor film is a pixel electrode of the acceptor substrate; And disposing the transfer layer on the pixel electrode of the acceptor substrate by irradiating a laser to a predetermined region of the donor film.

Hereinafter, with reference to the drawings showing embodiments of the present invention, the present invention will be described in more detail.

3 is a cross-sectional view illustrating a method of manufacturing a donor film according to the present invention.

Referring to FIG. 3, the donor film 260 includes a substrate substrate 250, a light-to-heat conversion layer 240, an intermediate layer 230, and a transfer layer 220.

The base substrate 250 serves as a supporting substrate, and the transparent substrate for transmitting light to the light-heat conversion layer 240 is made of a polymer material, for example, polyester, polyacryl, polyepoxy, polyethylene, and polystyrene. It consists of one or more polymer materials selected from. Preferably, the base substrate 250 is formed of polyethylene terephthalate (PET).

The light-to-heat conversion layer 240 is formed to have a predetermined thickness on the entire surface of the substrate substrate 250. The light-to-heat conversion layer 240 absorbs light in the infrared-visible light region and converts a portion of the light into heat. The light-to-heat conversion layer 240 has a suitable optical density and is a light absorbing material for absorbing light. Is formed. The light-to-heat conversion layer 240 includes an infrared light absorbent such as carbon black, graphite or infrared dyes, pigments in aluminum (Al), silver (Ag), and oxides and sulfides thereof.

The intermediate layer 230 is formed to have a predetermined thickness on the entire surface of the light-to-heat conversion layer 240. The intermediate layer 230 serves to prevent the light-heat absorbing material from contaminating or damaging the transfer layer 220 formed in a subsequent process step and to control the adhesion with the transfer layer 220 to improve transfer pattern characteristics. . The intermediate layer 230 is formed of a metal oxide, a nonmetal inorganic compound, or an inert polymer.

The transfer layer 220 is formed to have a predetermined thickness on the entire surface of the intermediate layer 230.

Meanwhile, the transfer layer 220 forms a low molecular weight organic material at a deposition rate of 1.1 to 10 kW / s using vacuum deposition or chemical vapor deposition (CVD). If the deposition rate of the transfer layer 220 is lower than 1.1 μs / s, the surface of the transfer layer 220 is not formed flat and projections appear. If the deposition rate is higher than 10 μs / s, the transfer layer 220 is deformed. . Most preferably, the transfer layer 220 is formed at a deposition rate of 1.8 mA / s. This is an optimal deposition rate for minimizing the roughness (RMS-ROOM MEAN SQUARE) of the surface of the transfer layer 220, the surface of the transfer layer 220 formed by this deposition rate is formed flat and dense. In more detail, the low molecular weight material has kinetic energy as the deposition rate is improved. Accordingly, the low molecular material is redeposited on the initially deposited low molecular material or rearranged around the initially deposited low molecular material to uniformly form the surface of the transfer layer 220. In addition, as the deposition rate is increased when the transfer layer 220 is formed, the transfer layer 220 is more densely formed, that is, cohesion strength is improved between the molecules forming the transfer layer 220 and the molecules. In the subsequent step, the transfer step 220 may prevent the transfer layer 220 from being buried or torn off the light-to-heat conversion layer 240.

The transfer layer 220 is formed of a low molecular organic material, for example, copper phthalocyanine (CuPc), N, N'-di (naphthalen-1-yl) -N, N'-dipetyl-benzidine (N, N'-Di (naphthalene-1-yl) -N, N'-diphenyl-benzidine; NPB) and tris-8-hydroxyquinoline aluminum (Alq3) . In addition, as the transfer layer 220 is formed of a low molecular organic material, the transfer layer 220 may include a hole injection layer (HIL), a hole transport layer (HTL), and an emission layer (EML). And one or more multilayer films selected from the group consisting of organic films, such as an electron transport layer (ETL) and the like.

4A and 4B are atomic force microscope (AFM) photographs of roughnesses of the surface of the transfer layer according to the present invention.

4A and 4B, the roughness of the surface of the transfer layer according to the deposition rate may be confirmed. In particular, looking at "B" and "C" representing the surface roughness of the transfer layer, when the deposition rate is 1.1 Å / s, the average value of the transfer layer surface ("B") roughness (RMS) is 2.4 nm and the deposition rate is 1.5 Å For / s, the average value of the transfer layer surface ("C") roughness (RMS) represents 1 nm.

Thus, as compared with the surface roughness of the regions "B" and "C", the higher the deposition rate, the flatter the surface of the transfer layer appears than when the deposition rate is low.

5A through 5E are cross-sectional views illustrating a method of manufacturing an organic light emitting display device using a donor film according to the present invention. For convenience of description, an explanation of an acceptor substrate on which a thin film transistor is formed will be omitted.

Referring to FIG. 5A, to manufacture the organic light emitting display device 200 according to the present invention, an acceptor substrate 210 is first prepared. The acceptor substrate 210 includes a thin film transistor, a pixel electrode layer electrically connected to the thin film transistor, and a pixel definition layer.

Referring to FIG. 5B, in order to transfer the transfer layer 220 of the donor film 260 to the pixel electrode of the acceptor substrate 210, the donor film 260 is spaced a predetermined distance apart from the upper portion of the acceptor substrate 210. Place it. In this case, the transfer layer 220 of the donor film 260 is disposed to face the acceptor substrate 210 on which the pixel electrode is formed.

The donor film 260 is formed on the base substrate 250, the light-to-heat conversion layer 240 formed on the base substrate 250, the intermediate layer 230 and the intermediate layer 230 formed on the light-heat conversion layer 240. It includes a transfer layer 220 formed on.

The base substrate 250 serves as a supporting substrate, and the transparent substrate for transmitting light to the light-heat conversion layer 240 is made of a polymer material, for example, polyester, polyacryl, polyepoxy, polyethylene, and polystyrene. It consists of one or more polymer materials selected from. Preferably, the base substrate 250 is formed of polyethylene terephthalate (PET).

The light-to-heat conversion layer 240 is formed to have a predetermined thickness on the entire surface of the substrate substrate 250. The light-to-heat conversion layer 240 absorbs light in the infrared-visible light region and converts a portion of the light into heat. The light-to-heat conversion layer 240 has a suitable optical density and is a light absorbing material for absorbing light. Is formed. The light-to-heat conversion layer 240 includes an infrared light absorbent such as carbon black, graphite or infrared dyes, pigments in aluminum (Al), silver (Ag), and oxides and sulfides thereof.

The intermediate layer 230 is formed to have a predetermined thickness on the entire surface of the light-to-heat conversion layer 240. The intermediate layer 230 serves to prevent the light-heat absorbing material from contaminating or damaging the transfer layer 220 formed in a subsequent process and to control the adhesion with the transfer layer 220 to improve transfer pattern characteristics. The intermediate layer 230 is formed of a metal oxide, a nonmetal inorganic compound, or an inert polymer.

The transfer layer 220 is formed to have a predetermined thickness on the entire surface of the intermediate layer 230.

Meanwhile, the transfer layer 220 forms a low molecular weight organic material at a deposition rate of 1.1 to 10 kW / s using vacuum deposition or chemical vapor deposition (CVD). When the deposition rate of the transfer layer 220 is lower than 1 Å / s, the surface of the transfer layer 220 is not formed flat, and projections appear. When the deposition rate is higher than 10 Å / s, the transfer layer 220 is deformed. Most preferably, the transfer layer 220 is formed at a deposition rate of 1.8 mA / s. This is an optimal deposition rate for minimizing the roughness (RMS-ROOM MEAN SQUARE) of the surface of the transfer layer 220, the surface of the transfer layer 220 formed by this deposition rate is formed flat and dense. In more detail, the low molecular weight material has kinetic energy as the deposition rate is improved. Accordingly, the low molecular material is redeposited on the initially deposited low molecular material or rearranged around the initially deposited low molecular material to uniformly form the surface of the transfer layer 220. In addition, as the deposition rate is increased when the transfer layer 220 is formed, the transfer layer 220 is more densely formed, that is, cohesion strength is improved between the molecules forming the transfer layer 220 and the molecules. In the subsequent step, the transfer step 220 may prevent the transfer layer 220 from being buried or torn off the light-to-heat conversion layer 240.

The transfer layer 220 is formed of a low molecular organic material, for example, copper phthalocyanine (CuPc), N, N'-di (naphthalen-1-yl) -N, N'-dipetyl-benzidine (N, N'-Di (naphthalene-1-yl) -N, N'-diphenyl-benzidine; NPB) and tris-8-hydroxyquinoline aluminum (Alq3) . In addition, as the transfer layer 220 is formed of a low molecular organic material, the transfer layer 220 may include a hole injection layer (HIL), a hole transport layer (HTL), and an emission layer (EML). And one monolayer film or one or more multilayer films selected from the group consisting of organic films, such as an electron transport layer (ETL).

Referring to FIG. 5C, the donor film 260 is laminated on the acceptor substrate 210. As the adhesion between the donor film 260 and the acceptor substrate 210 is better, the transfer efficiency of the transfer layer is improved in a subsequent transfer process step, so that the donor film 260 is adhered well on the acceptor substrate 210. Lamination is preferred. For example, the donor film 260 may be laminated on the acceptor substrate 210 using a roller. By moving the roller from side to side, the donor film 260 is removed by laminating a gas or the like that may exist between the acceptor substrate 210. Thereafter, the laser is irradiated on the donor film 260 facing the pixel electrode of the acceptor substrate 210.

Referring to FIG. 5D, a laser is irradiated to a predetermined region of the donor film 260, that is, the region of the donor film 260 corresponding to the pixel electrode of the acceptor substrate 210, so that the laser is emitted from the light-to-heat conversion layer 240. As the light is absorbed and converted into thermal energy to release heat, the adhesive force between the transfer layer 220 and the intermediate layer 230 is changed to separate the transfer layer 260 from the donor film 260. Accordingly, the transfer layer 220 is transferred onto the pixel electrode of the acceptor substrate 210 to form the emission layer 220b. At this time, the transfer layer 260 is transferred only to the area irradiated with the laser, the transfer layer 220a of the area not irradiated with the laser remains on the donor film 260 as it is. The method of forming the light emitting layer 220b by using the above-described principle is called laser induced thermal imaging (LITI).

Referring to FIG. 5E, when the light emitting layer 220b is formed on the pixel electrode of the acceptor substrate 210, the donor film 260 and the acceptor substrate 210 are separated. Accordingly, in the donor film 260, the base substrate 250, the light-to-heat conversion layer 240, the intermediate layer 230, and the transfer layer 220a of one region remain, and the acceptor substrate 210 is formed on the acceptor substrate 210. Red (R), green (G), and blue (B) pixels are transferred. Thereafter, the counter electrode layer 270 is formed on the acceptor substrate 210 on which the light emitting layer 220b is formed.

Although the present invention has been described in detail above, the present invention is not limited thereto, and many modifications are possible by those skilled in the art within the technical idea to which the present invention pertains.

As described above, according to the present invention, in the step of forming the transfer layer of the donor film, the transfer layer is formed at a deposition rate of 1.1 to 10 mW / s, thereby forming a uniform and dense surface of the transfer layer. This improves the adhesion between the transfer layer and the acceptor substrate and prevents the detachment of the transfer layer from the acceptor substrate.

Claims (7)

In the manufacturing method of the laser thermoelectric donor film, Forming a light-to-heat conversion layer on a base film composed of a polymer having transparency; And And forming a transfer layer made of a low molecular weight organic material on the light-to-heat conversion layer at a deposition rate of 1.1 to 10 kW / s. delete The method of claim 1, wherein the transfer layer is formed by one of vacuum deposition and CVD. The method of claim 1, further comprising forming an intermediate layer between the light-to-heat conversion layer and the transfer layer. The method of claim 1, wherein the transfer layer is a single layer film or at least one multilayer film selected from the group consisting of a light emitting layer, a hole injection layer, a hole transport layer, an electron injection layer and an electron transport layer. Preparing an acceptor substrate on which a pixel electrode is formed; A donor film including a base substrate on the substrate, a light-to-heat conversion layer formed on the base substrate, and a transfer layer made of a low molecular organic material formed at a deposition rate of 1.1 to 10 kW / s on the light-to-heat conversion layer. Preparing a; Disposing the transfer layer of the donor film toward the pixel electrode of the acceptor substrate; And And irradiating a laser to a predetermined region of the donor film to transfer the transfer layer onto the pixel electrode of the acceptor substrate.  The method of claim 6, wherein a predetermined region of the donor film is a region corresponding to the pixel electrode of the acceptor substrate.

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