JP4156891B2 - Thin film forming equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thin film forming apparatus for forming, for example, an organic thin film used for a light emitting layer of an organic LED element by vapor deposition.
[0002]
[Prior art]
In recent years, organic LED elements have attracted attention as elements for full-color flat panel displays. An organic LED element is a self-luminous element that emits light by exciting a fluorescent organic compound electrically. It has high brightness, high viewing angle, surface light emission, thin and multicolor emission, and low voltage of several volts. This is an all-solid-state device that emits light when a direct current is applied, and has a feature that its characteristic change is small even at a low temperature.
[0003]
FIG. 4 is a schematic configuration diagram of a vacuum deposition apparatus for producing a conventional organic LED element.
As shown in FIG. 4, in the organic thin film forming apparatus 101, an evaporation source 103 is disposed below the vacuum chamber 102, and a substrate 104 that is a film formation target is disposed above the evaporation source 103. Has been placed. An organic thin film having a predetermined pattern is formed by vapor-depositing an organic material evaporated from the evaporation source 104 on the substrate 104 through the mask 105 (see, for example, Japanese Patent Laid-Open No. 11-124667). ).
[0004]
[Patent Document 1]
JP-A-11-124667 Publication
[Problems to be solved by the invention]
However, in recent years, with the finer pitch of the mask, it has been difficult to obtain a uniform film thickness distribution with the conventional technique, which causes uneven emission of pixels and current flows in a thin film area. When it passes, the deterioration of the element is caused, and there is a problem that the lifetime of the organic LED element is limited.
[0006]
The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a thin film forming apparatus and a thin film forming method capable of forming an organic thin film having a uniform film thickness distribution.
[0007]
[Means for Solving the Problems]
The invention of claim 1, wherein has been made in order to achieve the above object, a vacuum chamber for forming a thin film with respect to the film-forming target, is disposed in the vicinity of the film-forming target, the width of the vertical and horizontal A mask having different openings, an evaporation source for evaporating an evaporation material containing an organic material , disposed in the vacuum chamber, and disposed so as to face the mask, A partition for partitioning a space between the evaporation source, the evaporation source having a container for storing the evaporation material including the organic material, and a heater provided in the vicinity of the top of the container, and the partition An elongated aperture for limiting the deposition area of the film formation target, and the aperture and the film formation target are in the width direction of the aperture and the length of the opening of the mask. To move relative to the direction. It is a thin film forming apparatus according to claim being.
According to a second aspect of the present invention, in the first aspect of the present invention, the mask is provided with a plurality of openings.
According to a third aspect of the present invention, in the second aspect of the present invention, the plurality of openings of the mask are arranged so as to face a certain direction.
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the aperture is configured to move among the aperture and the film formation target. .
The invention according to claim 5 is the invention according to claim 4, wherein the evaporation source is configured to move together with the aperture.
[0008]
In the case of the present invention having such a configuration, the aperture and the film formation target are configured to move relatively in the width direction of the aperture and in the longitudinal direction of the opening of the mask. Vapor of vapor deposition material including organic material flowing out from the aperture is uniformly deposited on the surface of the film formation target, making it possible to ensure uniform film thickness distribution over the film formation target. Become.
[0009]
As a result, according to the present invention, uneven emission of pixels can be prevented, and a long-life organic LED element can be efficiently manufactured.
[0010]
Further, in the present invention, in the space between the evaporation source and the mask, since the portion other than the aperture is partitioned by the partition portion, the heat from the evaporation source is difficult to be transmitted to the mask, thereby causing deformation of the mask. It is possible to prevent the deposition area from shifting.
[0011]
Furthermore, according to the present invention, when a mask having a plurality of openings is used to form a plurality of patterns on a large film formation target, or a film is formed on a plurality of film formation targets simultaneously. Even in the case of performing the above, it is possible to ensure uniform film thickness distribution for each part of the film formation target and for each film formation target.
[0012]
In this case, if the plurality of openings of the mask are arranged so as to face a certain direction, the relative movement direction of the aperture and the film formation target can be made constant, thereby enabling efficient film formation. It becomes possible.
[0013]
Further, if the aperture is configured to move among the aperture and the film formation target, it is possible to obtain a small thin film forming apparatus with a simple configuration.
[0014]
Furthermore, by moving the evaporation source together with the aperture, the relative positional relationship between the evaporation source and the aperture can be adjusted, thereby cutting the vapor deposition components incident on the film formation target from an oblique direction. Therefore, the film thickness distribution can be made more uniform.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of a thin film forming apparatus according to the present invention will be described in detail with reference to the drawings.
1 is a front sectional view of a preferred embodiment of a thin film forming apparatus according to the present invention, FIG. 2 (a) is a side sectional view of the thin film forming apparatus, and FIG. 2 (b) is the same embodiment. FIG. 3 is an explanatory view showing the relationship between the aperture and the mask.
[0016]
As shown in FIG. 1, a thin film forming apparatus 1 of the present embodiment has a vacuum chamber 2 connected to a vacuum exhaust system (not shown), and an evaporation source 3 is disposed below the vacuum chamber 2. Yes.
[0017]
As shown in FIG. 2, in the case of the present embodiment, the evaporation source 3 includes a rectangular container 30, and a predetermined organic vapor deposition material (for example, Alq3) 40 is accommodated in the container 30. ing. And it is comprised so that the vapor deposition material 40 may be heated with the heaters 31 and 32 provided in the upper vicinity of the container 30. FIG.
[0018]
On the other hand, a substrate holder 4 is provided above the vacuum chamber 2, and a substrate (film formation target) 5 on which a vapor deposition film is to be formed is fixed to the substrate holder 4. A mask 6 is provided near the lower portion of the substrate 5.
[0019]
As shown in FIG. 3, in the present embodiment, the mask 6 has a plurality of patterned openings 60 for depositing a predetermined thin film on the substrate 5.
[0020]
Furthermore, in the present embodiment, a partition 7 that partitions the space between the substrate 5 and the evaporation source 3 in the vacuum chamber 2 is provided.
[0021]
Here, the partition part 7 is made of a material such as aluminum (Al), for example, and is formed in a rectangular box shape having a predetermined size so as to cover the upper part of the evaporation source 3 described above. Yes.
[0022]
Moreover, this partition part 7 is comprised so that it may cool by circulating the cooling water etc. which are not shown in figure.
[0023]
As shown in FIGS. 1 and 2A and 2B, an elongated slit-shaped aperture 70 is opposed to the above-described mask 6 in the central portion of the upper portion of the partition portion 7 vertically above the evaporation source 3. It is provided to do.
[0024]
As shown in FIG. 3, the length in the X direction of the aperture 70 of the present embodiment is set so that the length is longer than the width of the substrate 5 to be deposited.
[0025]
In addition, the width of the aperture 70 is preferably smaller than the distance between the evaporation source 3 and the substrate 5 from the viewpoint of uniform film thickness, and more preferably, the distance between the evaporation source 3 and the substrate 5 is smaller. It is 1/3 or more and 1/3 or less.
[0026]
On the other hand, in the case of the present embodiment, the opening 60 of the mask 6 is formed in a rectangular shape having different vertical and horizontal widths.
[0027]
In this case, the size of each opening 60 is set so that the length Dy in the Y direction is larger than the length Dx in the X direction. Further, each opening 60 has a certain direction (in the present embodiment). In this case, they are arranged in parallel so as to face (Y direction).
[0028]
The opening 60 of the mask 6, the length Dx of about 30 m m the X-direction, Y-direction length Dy is about 60 m m.
[0029]
As shown in FIG. 1, in the present embodiment, the evaporation source 3 and the partition 7 are configured to move in synchronization in the same direction by using a moving mechanism having a ball screw or the like (not shown), for example. ing.
[0030]
In this case, the direction in which the evaporation source 3 and the partition portion 7 are moved is the width direction of the aperture 70 and the longitudinal direction of the opening 60 of the mask 6 (the arrow Y + direction or the Y− direction in FIG. 3).
[0031]
Further, the movement range of the evaporation source 3 and the partition portion 7 is a range from the home position indicated by a two-dot chain line in FIG. 1 to the aperture 70 crossing the entire surface of the substrate 5.
[0032]
Here, the arrows in FIG. 1 indicate the movement range of the central axis of the aperture 70 of the partition portion 7.
[0033]
In the present embodiment having such a configuration, first, the substrate 5 is carried into the vacuum chamber 2, the inside of the vacuum chamber is set to a predetermined pressure, and then the partition portion 7 is located at the standby position. The heaters 31 and 32 are energized, and evaporation of the vapor deposition material 40 is started.
[0034]
And the film-forming speed | rate of the vapor deposition material 40 which flows out from the aperture 70 of the partition part 7 is detected with the film thickness sensor which is not shown in figure, and when the value reaches | attains a predetermined value, the evaporation source 3 and the partition part 7 are made into a film-forming position. And move in the direction of arrow P.
[0035]
Immediately after this movement, the temperature of the heaters 31 and 32 of the evaporation source 3 is controlled to maintain the temperature of the vapor deposition material 40 at a predetermined temperature, thereby controlling the film deposition rate of the vapor deposition material 40 at a constant rate. Film formation is performed.
[0036]
And after the aperture 70 of the partition part 7 crosses the whole surface of the board | substrate 5, the evaporation source 3 and the partition part 7 are moved to the arrow Q direction toward a standby position. In this case, the temperature control of the heaters 31 and 32 of the evaporation source 3 is performed until the aperture 70 of the partition 7 crosses the entire surface of the substrate 5.
[0037]
And after the aperture 70 of the partition part 7 crosses the whole surface of the board | substrate 5, electricity supply to the heaters 31 and 32 is stopped.
[0038]
Thereafter, the substrate 5 is unloaded from the vacuum chamber 2, a new substrate 5 is loaded into the vacuum chamber 2, and the above-described steps are repeated.
[0039]
As described above, according to the present embodiment, the aperture 70 and the substrate 5 are configured to move relatively in the width direction of the aperture 70 and in the longitudinal direction of the opening 60 of the mask 6. Therefore, the vapor of the vapor deposition material flowing out from the aperture 70 is uniformly deposited on the surface of the substrate 5, so that it is possible to make the film thickness distribution particularly uniform.
[0040]
As a result, according to the present embodiment, it is possible to prevent uneven emission of pixels and to efficiently manufacture a long-life organic LED element.
[0041]
Further, in the present embodiment, in the space between the evaporation source and the mask 6, the portion other than the aperture 70 is partitioned by the partition portion, so that heat from the evaporation source is not easily transmitted to the mask 6, thereby It is possible to prevent the displacement of the vapor deposition region due to the deformation of 6.
[0042]
Furthermore, according to the present embodiment, when the mask 6 provided with the plurality of openings 60 is used to form a plurality of element patterns on the large substrate 5, or on a plurality of substrates (not shown). Even when film formation is performed simultaneously, the film thickness distribution can be surely made uniform for each part of the substrate 5 and for each substrate.
[0043]
In addition, by arranging the plurality of openings 60 of the mask 6 so as to face a certain direction, the relative movement direction of the aperture 70 and the substrate 5 can be made constant, thereby efficiently forming a film. Can do.
[0044]
Further, since the aperture 70 and the substrate 5 are configured so that the aperture 70 moves, a small thin film forming apparatus can be obtained with a simple configuration.
[0045]
Furthermore, in this embodiment, by moving the evaporation source 3 together with the aperture 70, the positional relationship between the evaporation source 3 and the aperture 70 is fixed, and the vapor deposition component incident on the substrate 5 from an oblique direction is cut. Therefore, the film thickness distribution can be made more uniform.
[0046]
The present invention is not limited to the above-described embodiment, and various changes can be made.
For example, in the above-described embodiment, the aperture is moved by moving the partition portion. However, the present invention is not limited to this, and it is also possible to move the substrate side.
[0047]
In addition, the shape of the aperture can be an elliptical shape, a circular shape, a quadrangular shape, or the like as long as it is an elongated shape.
[0048]
Furthermore, in the above embodiment, the partition portion and the evaporation source are reciprocated once during film formation, but may be reciprocated two or more times.
[0049]
Furthermore, this invention is not restricted to the apparatus for forming the organic thin film of an organic LED element, It can apply to various vapor deposition apparatuses. However, the present invention is particularly effective when an organic thin film of an organic LED element is formed using an organic material.
[0050]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a thin film forming apparatus capable of forming an organic thin film having a uniform film thickness distribution and preventing the influence of heat from the evaporation source.
[Brief description of the drawings]
FIG. 1 is a front cross-sectional view of a preferred embodiment of a thin film forming apparatus according to the present invention. FIG. 2 (a): a cross-sectional side view of the thin film forming apparatus (b): a partition portion of the same embodiment. FIG. 3 is an explanatory diagram showing the relationship between an aperture and a mask. FIG. 4 is a schematic configuration diagram of a conventional vacuum vapor deposition apparatus for producing an organic LED element.
DESCRIPTION OF SYMBOLS 1 ... Thin film formation apparatus 2 ... Vacuum chamber 2 3 ... Evaporation source 5 ... Substrate (film formation target) 6 ... Mask 7 ... Partition part 40 ... Deposition material 60 ... Opening part 70 ... Aperture

Claims (5)

A vacuum chamber for forming a thin film on the object to be deposited ;
A mask disposed in the vicinity of the film formation target and having openings with different vertical and horizontal widths;
An evaporation source disposed in the vacuum chamber for evaporating an evaporation material containing an organic material ;
A partition portion disposed to face the mask, and partitioning a space between the film formation target and the evaporation source,
The evaporation source has a container for storing an evaporation material containing the organic material, and a heater provided near the upper part of the container,
The partition portion is provided with an elongated aperture for limiting the vapor deposition region of the film formation target,
The thin film forming apparatus, wherein the aperture and the film formation target are configured to move relatively in the width direction of the aperture and in the longitudinal direction of the opening of the mask. The thin film forming apparatus according to claim 1, wherein the mask is provided with a plurality of openings. The thin film forming apparatus according to claim 2, wherein the plurality of openings of the mask are arranged so as to face a certain direction. 4. The thin film forming apparatus according to claim 1, wherein the aperture moves between the aperture and the film formation target. 5. The thin film forming apparatus according to claim 4, wherein the evaporation source is configured to move together with the aperture.

Images