JP2003077662A - Method and device for manufacturing organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems in a conventional manufacturing device that accurate control of a component ratio changing in the direction of thickness of a film is difficult and production of uniform products is impossible because, for example, a difference in light emitting colors occurs in each product. SOLUTION: A manufacturing method for an organic electroluminescent element having an inclined organic layer composed of a plurality of organic compounds of at least one layer between opposing anode electrode and cathode electrode and having different mixture ratios in the direction of thickness is provided to manufacture the inclined organic layer by moving a substrate 11 relatively for a plurality of evaporation sources 3 of the organic compound arranged across a partition plate 5 in the same vacuum film formation chamber 2. Moreover, a manufacturing device 1 for the organic electroluminescent element is provided to enable accurate control of a component ratio.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an organic electroluminescence device (hereinafter referred to as an organic EL element).
And a manufacturing apparatus for the organic layer in 1.

[0002]

2. Description of the Related Art Generally, an organic EL element using a low molecular weight material has a structure in which an organic thin film layer is sandwiched between electrodes. Up to now, several structures of this organic layer have been proposed. A typical example is that a hole-transporting material layer is deposited on a glass substrate on which an anode made of ITO (Indium tin oxide) is formed by a vacuum deposition method, and then an evaporation source is used as a hole-transporting material in the same vacuum device. To an electron transporting material, and an electron transporting material layer is vapor-deposited to form an organic layer having a laminated structure. Next, an organic EL in which a cathode made of a low work function metal material is formed
There is an element, and light is emitted from the organic layer when charges are injected from the electrodes.

Further, there has been proposed a structure (hereinafter referred to as an inclined structure) in which the organic materials of the respective layers described above are mixed so as to eliminate the interface of the laminated structure in the organic layer to give a concentration gradient of components. For example, US-PAT5853905, US-PAT5925980, US-PAT61
14055, US-PAT6130001, JP 2001-23776 A describes an organic EL element 10 (see FIG. 10) having a tilted structure.

In these patents, a layer having a concentration gradient (hereinafter referred to as a graded organic layer) changes the mixing ratio of the hole transporting material and the electron transporting material in the thickness direction. For example, according to Japanese Patent Laid-Open No. 2001-23776, as shown in FIG. 10, the organic layer 13 sandwiched between a positive electrode 12 and a negative electrode 14 laid on a substrate 11 made of glass or the like is composed of only a tilted organic layer. It is a single-layer structure, typically shown in FIG.
It has a concentration gradient of 1 and light is emitted from the inclined organic layer.

Also, an organic EL device having these tilt structures
In order to fabricate the element 10, conventionally, as shown in FIG. 17, a substrate insertion chamber 91, a plurality of film formation chambers 92, and a substrate removal chamber 9 are used.
3 and a device having a transfer arm 99 at the center for moving the substrate between different chambers. The tilted organic layer is formed in the film forming chamber 9 including the substrate rotating mechanism 95 as shown in FIG.
It is manufactured by using the manufacturing apparatus 90 provided with a plurality of evaporation sources 94 in 2. For example, the substrate 11 on which the thin film to be the positive electrode 12 is formed is set in the manufacturing apparatus 90 and rotated. Next, a thin film of the organic layer 13 is formed on the substrate 11 by the vacuum evaporation method. Each of the evaporation crucibles 94a and 94b is filled with a hole transporting material and an electron transporting material. In order to provide a concentration gradient, the electron transporting material controls the heater 96b or the like so that the evaporation rate increases with time, and the hole transporting material controls the heater 96a or the like so that the evaporation rate decreases with time. Controlled, simultaneous deposition of each material. The evaporation rate is controlled using the film thickness monitors 97a and 97b using a crystal oscillator. The reference numeral 98 in the drawing is an exhaust device.

[0006]

However, when an organic EL element having an inclined structure is manufactured using such an apparatus, there are the following problems.

Problem 1: Since it is necessary to control the ratio of two components that change in the thickness direction of the film, reproducibility is poor and variable evaporation rate control is difficult. Problem 2: When changing the film thickness, it takes a lot of time to set the conditions for the evaporation rate that changes with time. Problem 3: In order to make the component ratio uniform in the film surface direction, a mechanism for rotating the substrate is required, and in addition to the film formation time, rotation and substrate exchange time are required.

In order to solve the above problems, it is an object of the present invention to provide a method and a manufacturing apparatus capable of stably manufacturing an organic EL element having a tilt structure by a device having a relatively simple structure. I am trying.

[0009]

SUMMARY OF THE INVENTION The present invention is an organic electro-luminescent device having a tilted organic layer composed of at least one layer of a plurality of organic compounds between opposing anode and cathode electrodes and having a mixing ratio different in the thickness direction. A method for manufacturing a luminescence element, comprising moving a substrate relative to evaporation sources of a plurality of organic compounds arranged with a partition plate in the same vacuum film formation chamber, and / or the same vacuum film formation. By providing a manufacturing method and a manufacturing apparatus of an organic electroluminescence element, which is characterized in that a tilted organic layer is prepared by providing a plurality of evaporation sources having different evaporation amounts in a relative movement direction of a substrate in a room, An organic EL element having a so-called tilted organic layer can be stably manufactured.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to FIGS. Figure 1
Is a preferred organic EL device 10 having a tilted structure according to the present invention.
An embodiment of the manufacturing apparatus 1 (see FIG. 10) is shown. In the present invention, the tilted structure organic EL element 10 is manufactured using a so-called in-line type vacuum film forming apparatus. The in-line type vacuum film forming apparatus has a function of moving the substrate 11 at a constant speed and is composed of a plurality of film forming chambers 2. At least one of the film forming chambers includes two or more evaporation sources 3 and a vacuum evaporation apparatus in which a partition plate 5 for controlling the concentration gradient is placed between the evaporation sources 3.

In the drawing, reference numeral 11 is a substrate, which moves from the left to the right in the drawing at a predetermined speed. 1st in the figure
An example in which four film forming chambers from the film forming chamber 2a to the fourth film forming chamber 2d are provided is shown, and the substrate 11 is provided above each film forming chamber 2 (a to d).
There is provided a transfer chamber 2e in which is transferred. Further, all of these spaces 2a to 2e are in a vacuum state.

Each film forming chamber 2 (a to d) is provided with an evaporation source 3 for forming a film on the surface of the substrate 11 being conveyed. The evaporation source 3 differs depending on the structure of the organic EL element. For example, a hole injection layer in the first film forming chamber 2a, a tilted organic layer in the second film forming chamber 2b, a first cathode material in the third film forming chamber 2c,
The second cathode material is deposited in the fourth deposition chamber 2d. The material for forming a film in each film forming chamber and the number of film forming chambers are appropriately selected according to the structure of the organic EL element to be produced.

FIG. 2 shows a second film forming chamber 2 for forming a graded organic layer.
It is the schematic of b. In the lower part of the second film forming chamber 2b, evaporation sources 3a and 3b such as two crucibles, and a partition plate 5 arranged between the evaporation sources 3 (a and b) are installed, and the crucible evaporation sources are surrounded. Are provided with heaters 4a and 4b for controlling the temperature of each crucible evaporation source. An exhaust pump 6 can control the pressure in the film forming chamber to a predetermined value through a valve.

The organic EL element manufacturing apparatus according to the first embodiment of the present invention is configured as described above. By simultaneously depositing an organic material from the two crucible evaporation sources 3a and 3b,
The inclined organic layer can be formed on the surface of the substrate 11 being transported with good reproducibility.

Here, the relationship between the inclined organic layer to be formed and the partition plate 5 will be described. By adjusting the height of the partition plate 5, three types (types 1, 2, 3) of inclined structures as shown in FIG. 3 can be formed. Type 1, Type 2, and Type 3 can be formed by installing partition plates 5 as shown in FIGS. 4A, 4B, and 4C between evaporation sources. It should be noted that the reference numeral 7 (a, b) in FIG. 2 is a film thickness monitor, and the reference numeral Z in FIG. 4 is a boundary line of the component mixture that changes according to the height of the partition plate 5. is there.

Further, for example, in FIG. 4B, which is an apparatus for forming a type 2 inclined structure, a type 1 inclined structure can be formed by reducing the opening area of the deposition-inhibitory plate 8. The film thickness can be easily controlled by controlling the evaporation speed and the transport speed of the substrate 11.

By using the organic EL element manufacturing apparatus 1 provided with the film forming chamber provided with the partition plate 5 and the substrate 11 which moves in a fixed direction, the organic EL element having an inclined structure to be manufactured is reproduced. It can be easily manufactured with good performance. In particular, by controlling the constant evaporation rate of the evaporation source 3 and the transfer rate of the substrate 11 in accordance with the length of the partition plate 5 (distance between the partition plate and the substrate) and the opening area of the deposition-inhibitory plate 8, various values can be obtained. It is possible to obtain an organic EL device having a tilted structure.

In the present embodiment, the evaporation source 3 is not limited to the crucible and may be any of a point evaporation source, a linear evaporation source and a surface evaporation source. Further, the number of evaporation sources placed in a region (right side or left side in the drawing) partitioned by the partition plate 5 of the evaporation source unit is not limited to one, and two or more evaporation sources may be arranged. Further, the region partitioned by the partition plate 5 of the evaporation source section in one film forming chamber is not limited to two regions, and may be partitioned into three or more regions. For example, in the case of a film forming chamber divided into three regions, the arrangement is as shown in FIG. Further, the shape of the partition plate 5 is not limited to the plate shape, and may be, for example, the surrounding plate 15 that surrounds the evaporation source portion in a substantially cylindrical shape as shown in FIG. 5B.

Next, another embodiment will be described. It should be noted that parts having the same functions as those in the previous embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In this embodiment, a surrounding plate 9 surrounding the heated evaporation source 3 as shown in FIG. 6 is provided around the evaporation source portion. The surrounding plate 9 is the evaporation source 3
A plate made of a metal such as stainless steel or a ceramic material that surrounds a and 3b is installed at a proper distance from the evaporation source 3. The surrounding plate 9 can be controlled to a predetermined temperature by a temperature control device (not shown).

The organic material evaporated from the evaporation source is used in the film forming chamber 2
Inside, it spreads out almost radially and adheres to the substrate 11 and the like. At that time, if the surrounding plate 9 is installed in the scattering path and at a position that does not hinder the vapor deposition on the substrate, for example, in a region that covers a prospective angle that covers the scattering path flying toward the wall surface of the vacuum device, evaporation occurs. A part of the organic material that has flown from the source 3 also adheres to the surrounding plate 9.

At this time, if the temperature of the enclosing plate 9 is controlled to a high temperature, the organic material attached to the enclosing plate 9 is re-evaporated and attached to the substrate 11, so that the use efficiency of the material is significantly improved. In addition, the absolute amount of unused organic material adhering to the walls of the vacuum deposition chamber is reduced. This reduces the organic material that adheres to the wall surface and causes the generation of fine particle dust, so that the occurrence of defects due to the fine particle dust adhering to the substrate 11 is effectively prevented, and the yield is improved. The cost can be reduced.

The temperature of the surrounding plate 9 may be controlled to a temperature higher than the boiling point or the sublimation point of the evaporation material and lower than the temperature at which the material used is denatured. As the evaporation material, any of the materials generally used for organic EL elements can be used, and it can be applied to any organic material for forming an organic layer having a laminated structure, a single layer structure, or a gradient structure.

Next, a third embodiment will be described.
It should be noted that parts having the same functions as those in the previous embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In the above-described embodiment, the tilted organic layer is produced by moving the substrate relative to the evaporation sources of a plurality of organic compounds arranged with the partition plate in the same vacuum film forming chamber. In the embodiment, the inclined organic layer is produced by giving directivity to the direction in which the evaporation material is ejected from the evaporation source.

FIG. 12 shows an embodiment of an apparatus for manufacturing the organic EL element 10 (refer to FIG. 10) having a preferred inclined structure according to the present invention. Also in this embodiment, the organic E having the tilted structure is used.
The L element 10 is a so-called in-line type vacuum film forming apparatus 2
1 is used. It has a function of moving the substrate 11 at a constant speed, and is composed of a film forming chamber 22 having a plurality of evaporation sources 30 and an exhaust device 26. Further, load lock chambers 28a and 28b are provided before and after the film forming chamber. The evaporation source 30 has a directivity in the ejection direction and the evaporation material is scattered, and the evaporation materials from at least two evaporation sources are simultaneously formed on the substrate 11.

In the drawings, reference numeral 11 is a substrate, which moves from the left to the right in the drawing at a predetermined speed. In the figure, the load lock chamber 28a, the film formation chamber 22 and the load lock chamber 2 are shown.
A transfer chamber or the like in which the substrate 11 is transferred is provided above 8b. Further, the film forming chamber 22 is shown as a partition plate 25 in the figure.
According to (a, b), the first film forming chamber 22a and the second film forming chamber 22b
An example including three film forming chambers, that is, the third film forming chamber 22d is shown. It should be noted that these spaces are all vacuumed by the exhaust device 26.

In the figure, four evaporation sources 30 (a, b, 30) from a first evaporation source 30a to a fourth evaporation source 30d are provided in the film forming chamber 22.
c, d), and forms a film on the surface of the substrate 11 being conveyed. The evaporation range of each evaporation source 30 differs depending on the structure of the organic EL element. For example, in the first film forming chamber 22a, the hole injection layer is formed by the evaporation source 30a, in the second film forming chamber 22b, the inclined organic layer is formed by the evaporation source 30b and the evaporation source 30c, and the third organic layer is formed.
In the film forming chamber 22d, the cathode material is formed into a film by the evaporation source 30d. The material for forming a film in each film forming chamber, the number of evaporation sources, and the number of film forming chambers are appropriately selected according to the organic EL element structure to be produced.

FIG. 13 is a schematic view of the second film forming chamber 22b for forming the graded organic layer. Below the second film forming chamber 22b,
The two evaporation sources 30b and 30c are installed at a predetermined angle so that the evaporation material can be scattered with directivity so as to be in a predetermined irradiation range, and the temperature of the evaporation source is set around each evaporation source. Heaters 34b and 34c for controlling the temperature are provided. An exhaust pump 26 can control the pressure in the film forming chamber to a predetermined value through a valve. As shown in FIG. 14, the evaporation source 30 includes a cylindrical body 31, a storage portion 33 in which the evaporated material is exchangeably set inside the cylindrical body 31, and a predetermined size capable of scattering a predetermined amount of the evaporated material. A narrow rectangular slit 32a and a slit 32a at a predetermined angle α
An opening 32 having a V-shaped directivity range controller 32b that is widened around the evaporation source, and an evaporation source 3 provided around the opening 32.
The heater 34 controls the temperature of 0, and is preferably formed of carbon, but may be formed of ceramics such as boron nitride or alumina, or metals such as Ti, Al, and Cu.

The organic EL element manufacturing apparatus according to the third embodiment of the present invention is configured as described above, and has two evaporation sources 3
By simultaneously depositing an organic material from 0b and 30c, a tilted organic layer is formed on the surface of the substrate 11 being transported with good reproducibility.

Here, the inclined organic layer to be formed and the evaporation source 3
The relationship with 0b and 30c will be described. The organic compound serving as the evaporation source is filled in the storage portion 33 of the evaporation source 30, then fitted into the cylindrical body 31, heated by the heater 34, and scattered from the opening 32. At this time, the pointing range controller 32b controls the range of the scattered deposits at an angle of, for example, 33 ° with respect to the normal direction, and the length from the hole 32a is 1 °.
Since it is provided as cm, the scattering range of the deposited material is about 66
It can be controlled within the range of °. In this way, the evaporation sources 30b and 30c whose scattering range is controlled to a predetermined angle are fixed below the film formation chamber 22b by adjusting the directivity angle. Board 11
The evaporation range by the evaporation source 30b above is B, and the evaporation source 3
The evaporation range by 0c is shown as C. Evaporation sources 30b, 3
0c mounting angle, mounting position and opening 32
By adjusting (the hole 32a and the directivity range control unit 32b), the organic layer having the above-described inclined structure can be formed. For example, in FIG. 13, the evaporation source 30 is provided only on the evaporation range B on the substrate 11 conveyed from the left side of the drawing.
At the position where the vapor deposition product of b is formed and subsequently moves to the right to overlap the evaporation ranges B and C, both evaporation sources 30
The vapor deposits from b and 30c are vapor-deposited at the same time, and finally only the vapor deposit from the vaporization source 30c is formed in a position only in the vaporization range C. At this time, if it is assumed that the amount of the vapor deposition material that reaches the substrate from each vaporization source decreases toward the periphery of the vapor deposition range of the vaporization source, a gradient structure in which the mixing ratio is continuously changed is produced. can do. In particular, since the evaporation source tilted at a predetermined angle is used, the size of the manufacturing apparatus is larger than that in the case where the inclined organic layer is produced by increasing the distance from the evaporation source and using the area where the evaporation ranges from different evaporation sources overlap. It is possible to reduce the size and reduce the cost of the device and the installation space cost. In addition, what is indicated by the symbol Z is a boundary line of the component mixture of the vapor deposition.

By using the organic EL element manufacturing apparatus 21 including the film forming chamber provided with such an evaporation source 30 and the substrate 11 that moves in a fixed direction, the organic EL element having the inclined structure to be manufactured is reproduced. It can be easily manufactured with good performance. In addition, in this embodiment, the number of the evaporation sources 30 is not limited to one, and two or more evaporation sources may be arranged. Further, similarly, the film forming chamber for forming the organic layer having the inclined structure is not limited to one, and a plurality of film forming chambers may be provided.

Next, a fourth embodiment will be described.
It should be noted that parts having the same functions as those in the previous embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In the present embodiment, the tilted organic layer is created by arranging a plurality of evaporation sources in parallel with each other in which the amount of evaporation of the evaporation materials from the evaporation source is controlled. 15 and 16 are explanatory views of an evaporation source part for forming a film on the organic EL element 10 (see FIG. 10) having a preferable inclined structure according to the present invention. Also in the present invention, the organic EL element 10 having the inclined structure is manufactured by using a so-called in-line type vacuum film forming apparatus. The in-line type vacuum film forming apparatus has a function of moving the substrate 11 at a constant speed,
A film forming chamber 22 having a plurality of evaporation sources 30, and an exhaust device 26
It is composed by. Further, load lock chambers 28a and 28b are provided before and after the film forming chamber. The evaporation source 30 has a directivity in the direction in which it evaporates, and the evaporation material is scattered.
It is supposed that the films are simultaneously formed on the upper surface (see FIG. 12).

In the drawings, reference numeral 11 is a substrate, which moves from the left to the right in the drawing at a predetermined speed. Film forming chamber 22
Is equipped with a plurality of evaporation sources, and the substrate 1 is conveyed.
1. Form a film on the surface. For example, a hole injection layer is formed by the evaporation source 30a in the first film forming chamber 22a, an inclined organic layer is formed by the evaporation source 41 and the evaporation source 42 in the second film forming chamber 22b, and a cathode material is formed by the evaporation source 30d in the third film forming chamber 22d. Each film is formed. The material to be deposited in each deposition chamber, the number of evaporation sources, and the number of deposition chambers are appropriately selected according to the organic EL element structure to be produced (see FIGS. 12 and 15).

In the lower part of the second film forming chamber 22b, two long radiant heating type evaporation sources 41 and 42 are arranged in parallel so that the longitudinal direction is parallel to the substrate moving direction. 15B and the second evaporation source 42 are simultaneously vapor-deposited on the substrate 11, they are installed at a slight inclination with respect to the substrate normal direction. The substrate 11 moves from the left side to the right side of the paper in FIG. 15A, and from the back side to the front side of the paper in FIG. 15B. Also, evaporation sources 41 and 42
As shown in FIGS. 15A and 15B, is a box 43 that stores a predetermined amount of evaporated material, and a lid 4 that covers the opening of the box 43.
4, 45 and a heater 46 provided around the box 43 for controlling the temperature, and the lids 44, 45 are provided with a plurality of holes 47, 48 having a predetermined size. The lid 44 of the first evaporation source 41 is provided with holes 47a to 47f whose diameter gradually decreases as the substrate 11 moves, and the lid 45 of the second evaporation source 42 reversely moves as the substrate 11 moves. Holes 48a to 48f whose diameters gradually increase are provided. Although these evaporation sources are preferably formed of carbon, they may be formed of ceramics such as boron nitride and alumina, or metals such as Ti, Al, and Cu as in the third embodiment. is there. Further, as shown in FIG. 16, the distance between the holes 47 and 48 may be gradually changed.

The organic EL device manufacturing apparatus according to the fourth embodiment of the present invention is constructed as described above and has two evaporation sources 4.
By vapor depositing the organic material simultaneously from Nos. 1 and 42, it is possible to form the tilted organic layer on the surface of the substrate 11 being transported with good reproducibility.

Here, the inclined organic layer to be formed and the evaporation source 4
The relationship with 1, 42 will be described. The organic compound serving as the evaporation source reaches the substrate 11 through the holes 47 and 48 provided in the lids 44 and 45 of the evaporation sources 41 and 42. At this time, in the first evaporation source 41, the scattering amount of 47f is smaller than the scattering amount of the hole 47a. Therefore, the amount of vaporized material that reaches the substrate 11 decreases as the substrate 11 moves. On the contrary, in the second evaporation source 42, compared with the scattering amount of the holes 48a,
Since the scattering amount of f is large, the amount of vaporized substances reaching the substrate 11 increases as the substrate 11 moves. Evaporation sources 41, 42
By adjusting the mounting angle, the mounting position, the spacing and the size of the holes 47, 48, etc., the organic layer having the above-described inclined structure can be formed. Further, the uniformity of the organic layer formed on the substrate is improved by appropriately separating the distance between the evaporation source and the substrate.

By using the organic EL element manufacturing apparatus provided with the film forming chamber provided with such evaporation sources 41 and 42 and the substrate 11 that moves in a fixed direction, the organic EL element having the inclined structure to be manufactured is obtained. It can be manufactured easily with good reproducibility. Also in this embodiment, two or more evaporation sources may be arranged. Further, similarly, the film forming chamber for forming the organic layer having the inclined structure is not limited to one, and a plurality of film forming chambers may be provided. Further, each evaporation source 41, 42 is a lid 4 in which one box 43 is provided with a plurality of holes 47 or holes 48, respectively.
It is supposed that 4,45 are attached, but not limited to this,
For example, the evaporation source 41 is connected to the holes 47a, 47b, 47c, 47.
As a plurality of individually controllable independent evaporation sources corresponding to d, 47e, and 47f, divided evaporation sources such as those arranged in a line may be used as the evaporation source.

Further, also in the third and fourth embodiments, it is possible to provide a partition plate whose position can be adjusted as in the first and second embodiments, an adhesion preventing plate and a surrounding plate.
The substrate 11 may be a plate material or a film, glass,
It is possible to use an insulating material such as plastic on which a thin film functioning as an anode is formed. The evaporation method may be heating evaporation (resistance heating, EB heating), sputter evaporation, or the like.

In the above description, an example of a so-called horizontal placement device in which the substrates move in the horizontal direction has been shown. However, when the substrates are placed vertically, the two substrates are stacked back to back and conveyed. Alternatively, the film forming chambers may be arranged on both sides of the film forming chamber and the vapor deposition material may be blown from the side surfaces. As a result, two substrates can be formed at the same time, and the processing capacity can be doubled as compared with single-sheet feeding.

An example in which one kind of hole transporting material and one kind of electron transporting material are produced as the graded organic layer so as to have a predetermined concentration gradient has been described, but the invention is not limited to this.
The graded organic layer may be formed using more than one kind of material. Further, in the laminated organic EL element, two adjacent layers can be manufactured in combination with other layers.

[0040]

EXAMPLE An example of an apparatus for manufacturing an organic EL element having a tilted structure will be described below. Substrate is 200mm x 200mm Indium t
Glass with in oxide (ITO) was used. The structure of the manufactured device was hole injection layer / gradient structure layer / electron injection layer / cathode layer. The device was manufactured using an in-line device as shown in FIG. The substrate is put in from the first film forming chamber 2a side, and the speed is
It is conveyed at 1.3 mm / s and is ejected from the fourth film forming chamber 2d side.

In the first film forming chamber 2a, a thin film of copper phthalocyanine is formed and a hole injection layer is formed. Next, in the second film forming chamber 2b, the hole transporting material N, N'-di (1-naphthyl) -N, N'-diphenyl- [1,1'- having the molecular structure as shown in FIG. b
iphenyl] -4,4'-diamine (α-NPD) and the electron-transporting material (also serving as the light-emitting material) tris (8-hydroxyqu) shown in FIG.
The gradient structure layer is formed using inoline) aluminum (Alq3). The internal structure of the second film forming chamber 2b is as shown in FIG. The evaporation rate was adjusted so that the film thickness of the graded structure layer was 2000Å. Next, a Li thin film was formed in the third film forming chamber 2c to form an electron injection layer. Finally, the fourth film forming chamber 2d
Then, the cathode Al was formed into a film.

As a reference, α-NPD is set to 1
000Å and Alq3 were formed in the same process except that Alq3 was sequentially laminated with a thickness of 1000Å to produce an organic EL device.

The EL spectra of both devices are shown in FIG. This figure shows emission spectra based on Alq3 for both the example sample Q and the reference sample R, and the organic EL element 10 provided with the tilted organic layer having no change in basic emission characteristics was obtained. There is.

[0044]

EFFECT OF THE INVENTION Effect 1: In the conventional method, in order to form a concentration gradient, it is necessary to sequentially control the evaporation rate. On the other hand, in the present invention, while keeping the evaporation rate constant,
A concentration gradient is formed by moving the substrate. In the evaporation rate control by a film thickness monitor with a crystal oscillator, it is easy to control the evaporation rate to be maintained for a certain period of time, but it is difficult to control the evaporation rate to be changed successively with the current technology. Therefore, the present invention has the effect of increasing the reproducibility of the density gradient pattern.

Effect 2: The conventional cluster type vapor deposition apparatus is
When changing the film thickness of a film having a graded structure, it is necessary to redetermine the conditions for changing the evaporation rate with time, that is, the initial speed, the final speed, and the speed gradient. Further, since the evaporation rate is controlled by the film thickness monitor of the crystal oscillator, it is difficult to control the rate to be changed successively.
Therefore, with such a conventional method, it is difficult to change the film thickness at the production level. On the other hand, in the present invention, the film thickness can be easily changed only by changing the set evaporation rate or the moving speed of the substrate. Further, the concentration gradient can be easily changed by changing the height of the partition plate of the evaporation source or the evaporation source.

Effect 3: Conventionally, the substrate was rotated to obtain a film having a uniform film thickness. In addition, a transfer time is required every time the substrate is replaced. On the other hand, when the method of the present invention is used, since it is an in-line method, the transfer time is significantly shortened, and the time required for rotation of the substrate is also unnecessary. Therefore, the present invention has the effect of increasing the throughput of thin film production.

Effect 4: Generally, when the vacuum evaporation method is used, the ratio of the evaporated material used as a film on the substrate is 10% or less. Most of the evaporated material adheres to the inner wall of the vacuum container. This is because there is no directivity in the evaporation direction. On the other hand, when the method of placing the heated plate around the evaporation source of the present invention is used, the evaporation direction can be limited. Therefore, the present invention has the effect of increasing the efficiency of use of the evaporation material.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of a manufacturing apparatus and a manufacturing method of an organic electroluminescence element according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a film forming chamber for forming a graded structure layer which is a main part of the manufacturing apparatus and the manufacturing method according to the present invention.

FIG. 3 is a graph showing an example of a graded structure layer that can be formed according to the present invention.

FIG. 4 is an explanatory view showing the operation of the partition plate and the deposition preventive plate when forming the inclined structure layer.

FIG. 5 is an explanatory view showing another embodiment of a film forming chamber for forming a graded structure layer.

FIG. 6 is an explanatory view showing still another embodiment of a film forming chamber for forming a graded structure layer.

FIG. 7 is a structural formula showing a molecular structure of an organic material α-NPD used in Examples.

FIG. 8 is a structural formula showing a molecular structure of an organic material Alq3 used in Examples.

FIG. 9 is a graph showing an emission spectrum of an organic EL element formed by the manufacturing apparatus and the manufacturing method according to the present invention.

FIG. 10 is a cross-sectional view showing the structure of an organic EL element having a tilted structure.

FIG. 11 is a graph showing a concentration gradient of a graded structure layer.

FIG. 12 is a schematic cross-sectional view showing another embodiment of the apparatus for manufacturing an organic electroluminescence element according to the present invention.

13 is a schematic cross-sectional view showing a film forming chamber for forming a graded structure layer, which is a main part of the manufacturing apparatus and the manufacturing method of FIG.

FIG. 14 is an explanatory diagram showing an embodiment of an evaporation source for forming a gradient structure layer.

FIG. 15 is an explanatory diagram showing another embodiment of an evaporation source for forming a graded structure layer.

16 is an explanatory diagram showing a main part of a manufacturing apparatus and a manufacturing method for forming a graded structure layer using the evaporation source of FIG.

FIG. 17 is an explanatory diagram showing a manufacturing apparatus of a conventional example.

FIG. 18 is an explanatory diagram showing a main part of a manufacturing apparatus of a conventional example.

[Explanation of symbols]

1,21 ... Manufacturing equipment for organic EL devices 2, 22 ... Deposition chamber 3,30 ... Evaporation source 4,34 ... Heater 5,25 ... Partition board 6,26 ... Exhaust device 7, 27 ... Film thickness monitor 8 ... Protective plate 9 ... Enclosure 10 ... Organic EL element 11 ... Board 12 ... Positive electrode 13: Organic layer 14 ... Cathode 15 ... Surrounding plate 2e ... Transfer room 28 …… Road lock room 30 ... evaporation source 31 ... Cylinder 32 ... Opening 32a ... slit 32b ... Direction range control unit 33 ... Storage section 34 ... Heater 41, 42 ... Evaporation source 43 ... Box 44, 45 ... Lid 46 ... Heater 47, 48 ... holes

Claims (6)

[Claims] 1. A method for manufacturing an organic electroluminescent device, comprising an inclined organic layer composed of at least one layer of two or more kinds of organic compounds between opposing anode and cathode electrodes and having a mixing ratio different in the thickness direction. Therefore, the substrate is moved relative to the evaporation sources of a plurality of organic compounds arranged with a partition plate in the same vacuum film forming chamber, and / or the substrate is relatively moved in the same vacuum film forming chamber. Method for producing an organic electroluminescent device, characterized in that a tilted organic layer is produced by providing a plurality of evaporation sources having different evaporation amounts in different moving directions. 2. The method for producing an organic electroluminescence device according to claim 1, wherein the graded organic layer is composed of two or more kinds of organic compounds having different carrier transporting properties. 3. An organic compound layer including a first electrode and a second electrode, and a plurality of organic compound materials sandwiched between the electrodes, and an organic compound layer including a tilted organic layer having different mixing ratios in the thickness direction. An apparatus for manufacturing an organic electroluminescence element which emits light from an organic compound layer by an injected current, which is movable relative to an evaporation source and first and second evaporation source parts arranged at least with a partition plate in between. The partition plate overlaps with both the scattering paths of the first evaporation material scattered from the first evaporation source and the scattering paths of the second evaporation material scattered from the second evaporation source. A length that protrudes into the region and has such a length that both the first and second evaporation materials can reach the substrate, and the organic materials are simultaneously formed on the substrate from the first evaporation source and the second evaporation source. Scatter the material to the substrate surface An apparatus for manufacturing an organic electroluminescence device, which can produce a tilted organic layer in which a mixing ratio of a first evaporation material and a second evaporation material is different in a thickness direction. 4. An organic compound layer including a first electrode and a second electrode, and a plurality of organic compound materials sandwiched between the electrodes, and an organic compound layer including a tilted organic layer having different mixing ratios in the thickness direction. A device for manufacturing an organic electroluminescence element that emits light from an organic compound layer by an injected current, wherein a hole serving as a vapor deposit outlet and a pointing range expanding from the periphery of the hole from the evaporation source side toward the substrate side. At least two evaporation sources each having a control unit, and a substrate movable relative to the evaporation sources, wherein the evaporation source is a scattering path of the first evaporation material scattered from the first evaporation source, And both of the scattering paths of the second evaporation material scattered from the second evaporation source are overlapped, and the organic material is simultaneously scattered on the substrate from the first evaporation source and the second evaporation source, The first evaporation material and the And an apparatus for manufacturing an organic electroluminescence device capable of producing a graded organic layer in which the mixing ratio of the second evaporation material differs in the thickness direction. 5. An organic compound layer including a first electrode and a second electrode, and a plurality of organic compound materials sandwiched between the electrodes, and an organic compound layer including a tilted organic layer having different mixing ratios in the thickness direction. An apparatus for manufacturing an organic electroluminescence device, which emits light from an organic compound layer by an injected current, wherein at least two evaporation sources having a plurality of holes serving as vapor deposit emission ports and movable relative to the evaporation sources. The evaporation source, the evaporation paths of the first evaporation material scattered from the first evaporation source and the scattering paths of the second evaporation material scattered from the second evaporation source are overlapped with each other. And, the plurality of holes provided in each evaporation source are arranged in parallel substantially in parallel with the moving direction of the substrate, and the size of at least one hole is different from the size of the other holes. First evaporation source and second Of an organic electroluminescence device capable of producing an inclined organic layer in which the mixing ratio of the first evaporating material and the second evaporating material is different in the thickness direction by simultaneously scattering the organic material from the evaporation source on the substrate. apparatus. 6. The surrounding plate of the first evaporation source part, the second evaporation source part and the partition plate is provided with a heating controllable surrounding plate. An apparatus for manufacturing an organic electroluminescence element according to any one of 1.