KR101633112B1 - Source for vacuum thermal evaporation of organic thin film - Google Patents

Abstract

The present invention relates to a structure of a source used in an apparatus for forming an organic thin film by vacuum thermal deposition of an organic material. The apparatus for vacuum thermal deposition of organic thin film according to the present invention comprises: a vessel-shaped crucible for containing an organic material; A nozzle mounted on the crucible; And a spray plate spaced apart from the nozzle by a predetermined distance and capable of variably adjusting a spacing distance therebetween. Since the organic thin film vacuum thermal deposition apparatus according to the present invention includes a nozzle that can be variably controlled under various operating conditions, it is possible to control the deposition uniformity according to the deposition rate and the characteristics of the organic material.

Description

A SOURCE FOR VACUUM THERMAL EVAPORATION OF ORGANIC THIN FILM

The present invention relates to a source for a vacuum thermal deposition apparatus. In particular, the present invention relates to the structure of a source used in an apparatus for forming an organic thin film by vacuum thermal deposition of an organic material.

2. Description of the Related Art Recently, various flat panel display devices capable of reducing weight and volume, which are disadvantages of cathode ray tubes (CRTs), have been developed. Such flat panel display devices include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescence device. In particular, the electroluminescent device is divided into an inorganic light emitting diode display device and an organic light emitting diode display device depending on the material of the light emitting layer. Of these organic light emitting diode display devices, self light emitting devices, Brightness and viewing angle are large.

The organic light emitting diode display device has an organic light emitting diode (OLED) as shown in FIG. 1 is a schematic view showing the structure of an organic light emitting diode.

The OLED includes an organic compound layer that electroluminesces and a cathode electrode and an anode electrode that face each other with an organic compound layer interposed therebetween. The organic compound layer includes an electron injection layer (EIL), an electron transport layer (ETL), an emission layer (EML), a hole transport layer (HTL), and a hole injection layer HIL). ≪ / RTI > When a driving voltage is applied to the anode electrode and the cathode electrode, holes passing through the HTL and electrons passing through the ETL are transferred to the EML to form excitons, And emits visible light.

The organic light emitting diode display device forms an organic light emitting layer (EML) at a position where OLEDs are to be arranged in R (red), G (green), and B (blue) pixels for full color implementation. As a typical method of forming the organic light emitting layer (EML), there is a vacuum thermal evaporation method in which heat is applied to an organic light emitting material in a vacuum chamber to vaporize the organic light emitting material, and then the vaporized pressure is used to deposit the organic light emitting material on the substrate.

The apparatus for implementing the vacuum thermal evaporation method has a structure as shown in Fig. 2 is a view showing a structure of a vacuum thermal deposition apparatus.

A plurality of rotation bodies 40 are provided at the lower portion of the vacuum chamber 10 and include a plurality of insertion holes 30 capable of receiving the cylindrical source 20 and are rotatable by an external motor have. A substrate 50 for depositing an organic material is provided on the upper portion of the vacuum chamber 10. The rotating body 40 can be rotated to selectively deposit organic substances in the desired insertion port 30 on the substrate 50. In addition, the substrate 50 can be rotated by a remotely adjustable rotating means (not shown), and organic substances can be evenly deposited.

The organic material 60 is introduced into the source 20 and heated by the heater 70 provided around the source 20 to vaporize the organic material 60 so that the organic vaporizer 65 is supplied to the source 20 (Not shown). An organic vapor is deposited on the surface of the substrate 50 located above the vacuum chamber 10 to form an organic film 67. A mask 90 may be provided between the substrate 50 and the source 20 so that the organic film 67 has a predetermined shape and is deposited on the surface of the substrate 50. [

In the vacuum thermal deposition apparatus having such a structure, in order to make the thickness of the organic film 67 constant, a nozzle is designed and installed according to the operating conditions of the equipment. For example, as shown in FIG. 2, the source 20 (Type A, Type B, Type C, and Type) mounted with the various nozzles 80, D and Type E), and the organic film 67 can be deposited by selecting the desired source 20 from the outside with the regulator.

In the vacuum thermal vapor deposition apparatus having such a structure, the shapes and structures of the nozzles installed in one source are determined, so that they can not be utilized variously, and only a plurality of sources can be used. Therefore, the vacuum thermal deposition apparatus must be large-sized so that a large number of sources can be installed, thereby complicating the configuration of the entire system, and complicated and expensive maintenance.

It is an object of the present invention to provide a source with a nozzle that can be variably controlled in various operating conditions in an apparatus for vacuum thermal deposition of organic materials. Another object of the present invention is to provide a source capable of changing the deposition conditions of the organic vaporizer according to various operating conditions.

In order to achieve the above object, an organic thin film vacuum thermal deposition apparatus according to the present invention comprises: a vessel-shaped crucible for containing an organic material; A nozzle mounted on the crucible; And a spray plate spaced apart from the nozzle by a predetermined distance.

The distance between the nozzle and the spray plate can be variably controlled.

The nozzle including a circular nozzle hole; And the jetting plate is a disk-shaped.

And a ratio of a diameter of the nozzle hole to a diameter of the injection plate is 1: 2 to 3: 4.

The separation distance is at least 1 mm, and is 200% or less of the maximum nozzle hole diameter.

The injection plate further includes a conical protrusion protruding toward a central portion of the nozzle hole.

Wherein the crucible is open at one side and closed at the other side; Wherein the nozzle includes a nozzle body having one side open and the other side closed and a nozzle hole formed in the center of the closed other side; And an open side of the crucible and an open side of the nozzle body are coupled and separated from each other.

Wherein the nozzle body further comprises an outer threaded portion formed on an outer surface thereof; Wherein the spray plate support body further comprises an inner threaded portion formed on an inner surface of the other opened side; The inner threaded portion is fastened to the outer threaded portion so that the sprayed plate supporting body moves in both directions along the outer surface of the nozzle body.

As the spray plate supporting body moves in both directions along the outer surface of the nozzle body, the spacing distance between the spray plate and the nozzle hole is variably controlled.

And a heating device installed on the crucible, the nozzle, and the outside of the spray plate.

And the heating device applies higher heat to the spray plate than the crucible and the nozzle.

Since the organic thin film vacuum thermal deposition apparatus according to the present invention includes a nozzle that can be variably controlled under various operating conditions, it is possible to control the deposition uniformity according to the deposition rate and the characteristics of the organic material. Thus, using a single source, various deposition conditions can be varied from time to time to deposit an organic film. As a result, the organic thin film transfer apparatus according to the present invention can meet various deposition conditions and deposition targets very easily, without a complicated process using a single source. That is, when manufacturing an organic light emitting display device having various conditions, it does not cause a problem of complicated process, complexity of the device configuration, and cost increase.

Hereinafter, preferred embodiments of the present invention will be described with reference to FIGS. 3 to 6. FIG. 3 is a perspective view showing a transfer apparatus according to the present invention. 4 is a cross-sectional view showing a structure of a source used in a transfer apparatus according to a preferred embodiment of the present invention. 5 is a plan view of the source according to FIG. 4 viewed from above.

The source body 101 has a cylindrical insertion portion into which the cylindrical crucible 111 can be inserted. A heater 103 capable of applying heat to the outer wall of the crucible 111 is mounted on the inner wall of the insertion portion. The crucible 111 is hollowed to contain an organic material (not shown) therein, the bottom is clogged, and the top surface has an open cylindrical shape. A disk-shaped inner lid 121 having a plurality of concentric circular discharge holes 123 may be mounted on the open upper surface of the crucible 111. A short cylindrical nozzle 131 having a single open side surface that can engage with the open upper surface of the crucible 111 and a small nozzle hole 133 is provided on the other side. The inner diameter of the nozzle 131 and the inner diameter of the crucible 111 may be the same or the inner diameter of the nozzle 131 may be smaller to increase the vaporization pressure. When the nozzle 131 is coupled to the crucible 111, the organic lid 201 generated inside the crucible 111 can be supplied to the inner space of the nozzle at a high pressure with the inner lid 121 interposed therebetween.

The spray plate 153 is installed at a position spaced a predetermined distance above the nozzle 131 in order to spray the organic vaporizer 201 injected through the nozzle 131 with a more uniform distribution. In order to allow the spray plate 153 to float above the nozzle 131, the following structure can be used. The upper end of the outer wall of the nozzle 131 may include a male screw portion 135. The inner side wall of the lower surface of the spray plate supporting body 151, which has a short cylindrical shape and is open at both ends, may include a female screw portion 155 fastened to the male screw portion 135. The open top surface of the spray plate support body 151 includes a spray plate support 157 in the form of a wire capable of supporting the spray plate 153.

When the female screw portion 155 of the spray plate supporting body 151 is fastened to the male screw portion 135 at the upper end of the outer wall of the nozzle 131 and then the spray plate supporting body 131 is rotated, So as to have a desired separation distance. When the female screw part 155 and the male screw part 135 are right-handed, the injection plate 153 is positioned closer to the nozzle hole 133 when turned to the right, and when turned to the left, The distance from the nozzle hole 133 is further increased.

A brief description of how to operate such a source is as follows. An organic material (not shown) to be deposited is placed in the crucible 111. The inner lid 121 is placed on the open upper surface of the crucible 111 and the nozzle 131 is mounted. Although not illustrated in the drawings, screwing means can also be used to join the nozzle 131 to the crucible 111. The ejection plate supporting body 151 is coupled to the upper end of the outer wall of the nozzle 131 and the ejection plate supporting body 151 is appropriately rotated to set the separation distance between the nozzle hole 133 and the ejection plate 153. After the crucible 111 is joined to the nozzle 131 and the spray plate supporting body 151, the crucible 111 is inserted into the source body 101. When the heater 103 installed on the inner wall of the source body 101 is heated, the organic material is vaporized and the organic vaporizer 201 fills the inside of the crucible 111. The steam is introduced into the nozzle 131 through the discharge holes 123 of the inner lid 121 as the steam pressure of the organic vaporizer 201 inside the crucible 111 increases. The organic vaporizer 201 introduced into the high pressure state is injected to the outside of the nozzle through the nozzle hole 133 of the nozzle 131. Then, the organic vaporizer 201 ejected at a considerable pressure collides with the ejection plate 153. As a result, the organic vaporizer 201 is widely distributed toward the outer circumferential surface of the spray plate, and is uniformly distributed on the surface of a substrate (not shown) installed on the upper side along the outer circumferential surface.

In this case, it is preferable that the heater 103 not only heats the outer wall of the crucible 111 in order to vaporize the organic matter in the crucible 111, but also forms the nozzle 131 to be heated. In addition, when the organic vaporizer 201 injected at a high pressure through the nozzle hole 133 meets the spray plate 153 in a suddenly expanded space, the temperature can be lowered by adiabatic expansion. In this case, the organic material can be solidified under the spray plate 153, and if it is mistaken, the solidified organic material 211 may block the nozzle hole 133. 6 is a view showing a case where the organic material 211 solidified in the spray plate 153 clogs the nozzle hole 133. Fig.

Therefore, preferably, the heater 103 is preferably formed so as to be able to heat up to the spray plate supporting body 151. In addition, the spray plate support 157 may have a hot-wire structure such that the spray plate 153 is also heated through the spray plate support 157. More preferably, the heater 103 is configured to heat the spray plate supporting body 151 to a temperature higher than the crucible 111, thereby effectively preventing the organic matter from solidifying in the spray plate 153.

An advantage of the present invention is that the distance between the spray plate 153 and the nozzle hole 133 can be arbitrarily adjusted by the user. That is, it is possible to control the deposition uniformity according to the deposition rate and the characteristics of the organic material. The degree of diffusion can be controlled by controlling the distance between the spray plate 153 and the nozzle hole 133. The uniformity of the deposition can be controlled by adjusting the degree of diffusion of the organic material to be evaporated. Figs. 7A and 7B are diagrams showing changes in the degree of diffusion according to the distance between the ejection plate and the nozzle hole. Fig. As shown in FIG. 7A, when the injection plate 153 is close to the nozzle hole 133 (Gap A < Gap B), the pressure of the vaporized organic material 201 increases and the scattering scattering degree increases. In contrast, as shown in FIG. 7B, the pressure of the vaporized organic material 201 is lowered and the deposition scattering angle is decreased.

As a result, the geometrical relationship between the ejection plate 153 and the nozzle hole 133 plays an important role in adjusting the uniformity of deposition of the organic material. The most important consideration in this embodiment is the geometric relationship between the ejection plate 153 and the nozzle hole 133. [ 8 is a view showing the geometrical relationship between the ejection plate and the nozzle hole according to the present invention.

D2 = 1: 2 to 3:10, and most preferably 2: 3 when the diameter of the nozzle hole 133 is D1 and the diameter of the ejection plate 153 is D2, . The distance between the nozzle hole 133 and the ejection plate 153 is preferably adjustable within 200% of the nozzle hole 133 at a minimum of 1 mm.

9, it is more preferable that the ejection plate 153 has a structure in which a portion facing the nozzle hole 133 protrudes toward the nozzle hole 133 in the cross-sectional shape of the ejection plate 153. [ 9 is a cross-sectional view showing another embodiment of the ejection plate according to the present invention. For example, it is preferable to form a conical or conical protrusion 153a on the center middle of the ejection plate 153. This smoothly guides the flow of the organic vaporizer 201 sprayed through the nozzle hole 133 toward the edge of the spray plate 153 and causes the vortex due to the collision between the organic vaporizer 201 and the spray plate 153 . That is, the flow of the organic vapor is guided to the edge of the spray plate 153 to smoothly maintain the injection flow. As a method for forming the protrusion 153a, a method of applying pressure using a tool having a pointed end at the center of the upper surface of the ejection plate 153 can be used. Then, a conical or conical depression 153b is formed naturally on the top surface of the center of the ejection plate 153.

Referring to FIG. 5 again, when the spray plate 153 is viewed from above, a space for spraying organic vapor is formed in the space between the spray plate 153 and the spray plate support 157. Therefore, it is not preferable if the spray plate support 157 occupies too much area. In the present invention, the shape of the spray plate support 157 is most preferably a wire shape. The spray plate support 157 is to maintain the spray plate 153 in a horizontal state by the organic vaporizer injected at a high pressure. Therefore, as shown in FIG. 5, the supporting members may be formed of four supporting members. In some cases, three supporting members may be distributed equally as shown in FIG. 10 is a view showing a configuration of a jet plate and a jet plate support according to the present invention. 11A and 11B, the spray plate 153 and the spray plate support 157 may be formed by removing a certain portion from a single thin disk, and then joined to the spray plate support body by welding or the like . 11A and 11B are views showing still another shape of the spray plate and the spray plate support according to the present invention.

As a means for adjusting the distance between the nozzle hole 133 and the ejection plate 153 by moving the position of the ejection plate 153 up and down may be artificially adjusted, As shown in Fig.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

1 is a schematic view showing the structure of an organic light emitting diode (OLED).

2 is a view showing a structure of a vacuum thermal deposition apparatus;

3 is a perspective view showing a transfer apparatus according to the present invention.

4 is a sectional view showing the structure of a source used in a transfer apparatus according to a preferred embodiment of the present invention.

5 is a plan view of the source according to FIG. 4 viewed from above;

6 is a view showing a case where an organic material solidified in an ejection plate clogs a nozzle hole;

FIGS. 7A and 7B are diagrams showing changes in the degree of diffusion according to the distance between the ejection plate and the nozzle hole. FIG.

8 is a view showing a geometrical relationship between a nozzle plate and a nozzle plate according to the present invention.

FIG. 9 is a sectional view showing another embodiment of the ejection plate according to the present invention. FIG.

10 is a view showing a configuration of a jet plate and a jet plate support according to the present invention.

11A and 11B are views showing still another shape of the spray plate and the spray plate support according to the present invention.

Description of the Related Art

10: vacuum chamber 20: source

30: insertion port 40: rotating body

50: substrate 60: organic material

67: organic film 90: mask

101: source body 70, 103: heater (heater)

111: Cylindrical crucible 121: Inner lid

123: discharge hole 80, 131: nozzle

133: nozzle hole 135: male thread portion

151: jetting plate supporting body 153: jetting plate

153a: protrusion 153b:

155: female thread part 157: spray plate support

65, 201: organic vaporizer 211: solidified organic matter

Claims (13)

A crucible in the form of a bowl capable of containing an organic substance; A inner lid mounted on the upper part of the crucible; A nozzle mounted on an upper surface of the crucible; And a spray plate spaced apart from the nozzle by a predetermined distance to diffuse the organic vapor of the organic material sprayed from the nozzle. The method according to claim 1, Wherein a distance between the ejection plate and the nozzle is variably controlled. The method according to claim 1, The nozzle including a circular nozzle hole; Wherein the injection plate is a disk-shaped substrate. The method of claim 3, Wherein the ratio of the diameter of the nozzle hole to the diameter of the injection plate is 1: 2 to 3: 4. The method of claim 3, Wherein the spacing distance is at least 1 mm and not more than 200% of the maximum nozzle hole diameter. The method of claim 3, Further comprising a conical protrusion protruding toward a central portion of the nozzle hole at a central portion of the ejection plate. The method according to claim 1, Wherein the crucible is open at one side and closed at the other side; Wherein the nozzle includes a nozzle body having one side open and the other side closed and a nozzle hole formed in the center of the closed other side; Wherein an open side of the crucible and an open side of the nozzle body are coupled and separated from each other. 8. The method of claim 7, The spray plate is fixed by a spray plate support formed on one opened side of the cylindrical spray plate support body; And the other opening side of the spray plate supporting body is engaged with and disengaged from the other end side of the nozzle body. 9. The method of claim 8, Wherein the nozzle body further comprises an outer threaded portion formed on an outer surface thereof; Wherein the spray plate support body further comprises an inner threaded portion formed on an inner surface of the other opened side; Wherein the inner threaded portion is fastened to the outer threaded portion so that the sprayed plate supporting body moves in both directions along the outer surface of the nozzle body. 10. The method of claim 9, Wherein a distance between the injection plate and the nozzle hole is variably controlled as the injection plate supporting body moves in both directions along the outer surface of the nozzle body. 10. The method of claim 9, Further comprising a driving unit for rotating the spray plate supporting body located outside the crucible, wherein the spray plate supporting body is remotely moved in two directions using an external electric signal, . The method according to claim 1, And a heating device installed on the outside of the crucible, the nozzle, and the ejection plate. 13. The method of claim 12, Wherein the heating device applies higher heat to the spray plate than the crucible and the nozzle.

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