JP2011153379A - Heating vessel of organic thin film deposition device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating vessel of an organic thin film deposition device in which an organic material is not modified. <P>SOLUTION: In the heating vessel of an organic thin film deposition device including a body in which a space part stored with an organic material is formed at the inside, and at least one or more discharge holes are formed at a closed upper part, and a heater provided to the outer circumferential face of the body, the size of the discharge hole is set by the volume of the body and a vapor deposition rate. For example, in the case where the volume of the body is 20 to 200 cc, the discharge hole(s) is caused to have a diameter of 5 to 25 mm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a heating container of an organic thin film forming apparatus, and by controlling the size of the discharge hole of the heating container, the organic material can be prevented from being deteriorated due to high temperature and high pressure, thereby heating the organic thin film forming apparatus without wasting organic material. Concerning the container.

  The electroluminescent element is an active light emitting display element, and not only has a wide viewing angle and excellent contrast, but also has a high response speed, and has attracted attention as a next generation display element. The electroluminescent device is divided into an inorganic electroluminescent device and an organic electroluminescent device by the light emitting layer forming material. Here, the organic electroluminescent element has an advantage that it is excellent in luminance, driving voltage and response speed characteristics and can be multicolored as compared with the inorganic electroluminescent element.

  In a general organic electroluminescent device, a positive electrode layer having a predetermined pattern is formed on the substrate. A hole transport layer, a light emitting layer, and an electron transport layer are sequentially formed on the positive electrode layer, and a negative electrode layer having a predetermined pattern is formed on the upper surface of the electron transport layer in a direction perpendicular to the positive electrode layer. ing. Here, the hole transport layer, the light emitting layer, and the electron transport layer are organic thin films made of an organic compound.

In the process of manufacturing the organic electroluminescent device having such a structure, the organic thin film of the hole transport layer, the light emitting layer, and the electron transport layer has a vacuum chamber in which the internal pressure is adjusted to 10 ⁻⁶ to 10 ⁻⁷ torr and the inside thereof. It is formed by a vapor deposition apparatus that is provided so as to face the substrate and includes a heating container in which a small amount of organic substance is accommodated and a heater provided in the heating container for heating and sublimating the organic substance.

  The importance of the heating container is required in the process of depositing the organic thin film by the heating container of the organic thin film forming apparatus described above. For example, when the upper part of the heating container is completely opened, the uniformity of the organic thin film deposited on the substrate is reduced, and at the same time, the internal temperature is not uniform. Various methods have been developed to solve these problems. As disclosed in Japanese Patent Laid-Open No. 12-223269, a large number of small-sized heating containers whose upper portions are completely opened are formed to improve the uniformity of the organic thin film and improve the controllability of the internal temperature. A method of making it devised. Alternatively, the upper portion of the heating container is formed by a point source discharge hole, or the opening 1 of the main body 4 of the heating container 10 is sealed with the cover 6 as shown in FIG. A method of forming the hole 6a has been devised. In this case, the organic material 2 accommodated inside the main body 4 is discharged to the outside of the heating container 10 through the discharge hole 6a at a high pressure by heating of the heater 3 and is deposited on the substrate, thereby suppressing the consumption of the organic material. In addition, the above-mentioned problems such as the uniformity of the organic thin film deposited on the substrate can be solved.

  However, in this case, if the discharge hole of the point source and the discharge hole of the cover that seals the opening are too small compared to the volume of the heating container, the temperature rises to increase the deposition rate and reaches the decomposition and modification temperature of the material. Have the problem of

  In addition, the organic material is decomposed and modified by high temperature and high pressure, so that there is a problem that consumption of the organic material increases.

  In addition, when the organic material is decomposed and modified, there is a problem that the composition of the organic thin film deposited on the substrate changes.

JP-A-12-223269

  The present invention has been made in consideration of the above points, and an organic material in which the volume of the heating container, the amount of the organic material, and the size of the discharge hole are adjusted by the organic material so that the organic material is not denatured. There is an object to provide a heating container of a thin film forming apparatus.

  In order to achieve the above object, the heating container of the organic thin film forming apparatus of the present invention is a main body in which a space portion in which an organic material is accommodated is formed and at least one discharge hole is formed in a sealed upper portion. In the heating container of the organic thin film forming apparatus including the heater provided on the outer peripheral surface of the main body, the size of the discharge hole is set by the volume of the main body, the amount of the organic material, and the organic material.

  When the volume of the main body is 20 cc or more and 200 cc or less, the discharge hole formed in the upper part has a diameter of 5 mm or more and 25 mm or less.

  Further, when the substrate-evaporation source distance is 300 mm or more and 1000 mm or less and the vapor deposition rate is 1 kg / sec or more, the discharge hole formed in the upper part has a diameter of 5 mm or more and 25 mm or less.

It is sectional drawing of the heating container of a normal organic thin film forming apparatus. 1 is a schematic cross-sectional view of an organic thin film forming apparatus according to an embodiment of the present invention. It is sectional drawing of the heating container of the organic thin film forming apparatus by one Embodiment of this invention. It is a perspective view of the heating container of the organic thin film forming apparatus of FIG. It is a perspective view which shows that many discharge holes of the heating container by this invention were formed. It is a perspective view which shows that the upper part of the heating container by this invention was sealed, and the discharge hole was formed in the center part. FIG. 5 is a perspective view showing that the upper part of the heating container according to the present invention is sealed and a plurality of discharge holes are formed in the central part. 2 is a diagram illustrating an entire area of a suitable discharge hole according to a main body volume of a heating container according to the present invention. 3 is a diagram illustrating an entire area of a suitable discharge hole according to the amount of organic material of a heating container according to the present invention.

  Hereinafter, a heating container of an organic thin film forming apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  In the organic thin film forming apparatus, as shown in FIG. 2, a substrate 22 on which an organic thin film is to be vacuum-deposited is provided inside the vacuum chamber 21, and an organic material is applied to the lower surface of the vacuum chamber 21 corresponding to the substrate 22. A mask provided with a heating container 30 for sublimation and having an opening having the same pattern as the pattern on which the organic thin film is to be deposited on the substrate 22 on the side close to the substrate 22 between the substrate 22 and the heating container. 23 is provided. The mask 23 is supported by a mask frame 24. A magnet unit 25 for bringing the mask 23 supported on the mask frame 24 into close contact with the substrate 22 is driven on the substrate 22 so that the mask 23 is in close contact with the substrate 22.

  3 and 4, the heating container 30 of the organic thin film forming apparatus according to the embodiment of the present invention includes a main body 33 that contains an organic material, a cover 36 that is coupled to the main body 33, and the main body. And a heater 34 that is provided in contact with the outer peripheral surface of 33 and heats the main body 33.

  The main body 33 has an opening 31 formed on the side corresponding to the substrate 22, and a space 32 in which the organic material 2 is accommodated. A heater 34 for heating and sublimating the organic material 2 accommodated in the space 32 is provided on the side surface of the main body 33, and a temperature for measuring the temperature of the organic material 2 is provided on the lower surface of the main body 33. Measuring means (not shown) are provided.

  As shown in FIG. 4, the cover 36 is coupled to the upper portion of the main body 33 of the heating container to seal the opening 31. At least one discharge hole 37 is formed in the central portion of the cover 36. The heated organic material 2 is discharged through the discharge hole 37. FIG. 5 shows a cover 36 in which a large number of discharge holes 37 are formed.

  Further, as shown in FIG. 6A or 6B, another cover 36 is not formed, and the upper portion 33a of the main body 33 may be hermetically sealed and at least one discharge hole 37 may be formed at the center thereof. .

  The discharge hole 37 is adjusted by the amount of the organic material 2 and the volume of the main body 33.

  When the discharge hole 37 is small, the vapor deposition rate is low. Therefore, in order to obtain a predetermined vapor deposition rate, the material is heated by the heater 34 and reaches the decomposition temperature of the material. Resulting in. Therefore, the organic material 2 present inside the main body 33 is easily deformed to produce a denatured product. When such a modified product is deposited on a substrate, current-voltage characteristics and emission chromaticity are abnormal. In order to prevent such high temperature and high pressure inside the main body, the size of the discharge hole 37 is formed to be proportional to the volume of the main body 33 and the amount of the vapor deposition rate. That is, as shown in FIG. 7 or FIG. 8, the organic material 2 easily becomes high temperature and high pressure by increasing the discharge hole 37 as the volume of the main body 33 increases and the amount of the deposition rate increases. To prevent.

  When the volume of the main body is 20 cc or more and 200 cc or less, the size of the discharge hole formed in the upper part is desirably 5 mm or more and 25 mm or less.

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

<Embodiment 1>
When about 5 g of the organic material disclosed in JP-A-10-88121 is used, the volume of the main body is 50 cc, the diameter of the discharge hole is 15 mm, the distance between the heating container and the substrate is 350 mm, and the deposition rate is 2 mm / s. When heating is performed, the maximum temperature of the organic material is 240 ° C., and it is deposited until the organic material disappears, that is, with a stable deposition rate of 2 ± 0.1 cm / s for 12 hours or more. Is done. Further, the degree of vacuum inside the main body increases to 1 × 10 ⁻⁴ or more and does not deteriorate. Therefore, the characteristics of the organic electroluminescent element formed under such conditions are good.

<Comparison 1>
An organic material was vapor-deposited on the substrate under the same conditions as in Embodiment 1 except that the diameter of the discharge hole was 2 mm. In this case, the maximum temperature of the organic material is 300 ° C. or higher, and it is deposited with a stability of the deposition rate of 2 ± 0.5 Å / s for about 5 hours. There is a risk of forming a thin film. Further, the degree of vacuum inside the main body increases rapidly from 1 × 10 ⁻⁴ to 1 × 10 ⁻² . An organic electroluminescent element is caused to have a chromaticity abnormality by the deposition of the modified organic material on the substrate.

<Embodiment 2>
When about 5 g of the organic material disclosed in JP-A-10-72579 is used, the volume of the main body is 50 cc, the diameter of the discharge hole is 15 mm, the distance between the heating container and the substrate is 350 mm, and the deposition rate is 2 率 / s. When the heating is performed, the maximum temperature of the organic material is 360 ° C., and it has a good deposition rate stability of 2 ± 0.1 Å / s for 12 hours or more until the organic material is used up. Further, the degree of vacuum inside the main body increases to 1 × 10 ⁻⁴ or more and does not deteriorate. Therefore, the characteristics of the organic electroluminescent element are good.

<Comparison 2>
An organic material was deposited on the substrate under the same conditions as in Embodiment 2 except that the diameter of the discharge hole was 2 mm. In this case, the maximum temperature of the organic material becomes 400 ° C. or higher, and the organic material may be deformed or deteriorated. However, it is deposited until the organic material disappears, that is, with a good deposition rate stability of 2 ± 0.1 Å / s for about 12 hours. And the degree of vacuum inside the main body does not increase to 1 × 10 ⁻⁴ or more. Therefore, the chromaticity abnormality occurs in the organic electroluminescence device by depositing the deformed organic material on the substrate.

<Embodiment 3>
When about 5 g of organic material disclosed in Japanese Patent Laid-Open No. 8-333569 is used, the volume of the main body is 50 cc, the diameter of the discharge hole is 15 mm, the distance between the heating container and the substrate is 350 mm, and the deposition rate is 2 Å / s. When the organic material is heated, the maximum temperature of the organic material is 320 ° C., and the organic material is vapor-deposited until the organic material disappears, that is, with a good deposition rate stability of 2 ± 0.1 kg / s for 12 hours or more. . Further, the degree of vacuum inside the main body increases to 1 × 10 ⁻⁴ or more and does not deteriorate. Therefore, the characteristics of the organic electroluminescent element are good.

<Comparison 3>
An organic material was deposited on the substrate under the same conditions as in Embodiment 3 except that the diameter of the discharge hole was 2 mm. In this case, the maximum temperature of the organic material may be 400 ° C. or higher, and the organic material may be deformed or altered to produce a modified product. It is deposited with a stability of a good deposition rate of 2 ± 0.1 liter / s for about 8 hours, and the remainder is not deposited due to deformation or alteration. However, the degree of vacuum inside the main body does not increase to 1 × 10 ⁻⁴ or more. Therefore, the chromaticity abnormality occurs in the organic electroluminescence device by depositing the deformed organic material on the substrate. Organic materials that produce a lot of residue cannot be used effectively.

  When comparing the above embodiment with the comparative embodiment, it can be seen that the characteristics of the organic thin film are determined by the type and amount of the organic material and the size of the discharge hole depending on the volume of the main body in which the organic material is accommodated.

  The operation of the heating container of the organic thin film forming apparatus according to the present invention configured as described above will be described as follows.

  First, in order to form an organic thin film on a substrate using an organic thin film forming apparatus, an organic material for forming an electron transport layer, a light emitting layer, or a hole transport layer is injected into the space inside the heating container. The organic material is heated and sublimated by a heater provided on the circumferential surface of the main body. The sublimated organic material is deposited on the substrate through a discharge hole in the cover of the heating container to form an organic thin film. By increasing the diameter of the discharge hole depending on the type of organic material, the volume of the main body, and the deposition rate, the organic material can be prevented from being easily decomposed and denatured at high temperatures and high pressures.

  As described above, the organic material sublimated without being decomposed or modified is discharged through the discharge hole of the cover, and then deposited on the substrate with the same composition as the material.

  Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is only an example, and those skilled in the art can make various modifications and other equivalent embodiments. You can understand that. Therefore, the true protection scope of the present invention must be determined by the claims.

(The invention's effect)
As described above, the heating container of the organic thin film forming apparatus according to the present invention can prevent decomposition and modification of the organic material by preventing the high temperature inside the heating container by adjusting the size of the discharge hole.

  In addition, by adjusting the size of the discharge hole, it is possible to prevent the organic material from being decomposed and denatured by preventing the pressure from increasing due to the rapid increase in the degree of vacuum inside the heating container.

  Further, it is possible to prevent chromaticity abnormality that occurs when the organic material is decomposed, modified, and deposited on the substrate.

33 Body 34 Heater 36 Cover 37 Discharge hole

Claims (3)

A method of performing vapor deposition of an organic material in an organic thin film forming apparatus provided with a substrate and a heating container disposed below the substrate,
The heating container includes a main body in which one or more discharge holes are formed in a sealed upper portion where a space portion in which an organic material is accommodated is formed, and a heater provided on an outer peripheral surface of the main body,
The organic material vapor deposition method, wherein the size of the discharge hole of the heating container is set by the volume of the main body, the amount of the organic material, and the organic material.   2. The organic material deposition method according to claim 1, wherein when the volume of the main body is 20 cc or more and 200 cc or less, the discharge hole formed in the upper part has a diameter of 5 mm or more and 25 mm or less.   When the distance between the substrate and the evaporation source is 300 mm or more and 1000 mm or less and the deposition rate is 1 kg / sec or more, the discharge hole formed in the upper part has a diameter of 5 mm or more and 25 mm or less. Item 2. A method for depositing an organic material according to Item 1.

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