JP2008106310A - Vapor deposition system and vapor deposition method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor deposition system where the using efficiency of an organic material is high, and an organic film can be uniformly formed in the vapor deposition area to be required. <P>SOLUTION: In the vapor deposition system where an organic film is vapor-deposited on a substrate using a planar vapor deposition source 10 having two-dimensionally distributed crucibles 11, regarding the planar vapor deposition source 10, the arrangement density of the crucibles 11 in the peripheral region 10b is made higher than the arrangement density of the crucibles 11 in the inside region 10a. Since the vapor amount of organic matter generated around each crucible 11 is small in the peripheral region 10b, by increasing the arrangement density of the crucibles 11 for covering the same, the non-uniformity in the film thickness of an organic film vapor-deposited on a substrate is prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vapor deposition apparatus and a vapor deposition method for depositing and forming an organic film used particularly for organic EL, organic TFT, organic solar battery and the like.

  In recent years, organic electronics devices using organic materials instead of silicon devices have been rapidly developed. In order to succeed in organic electronic devices, it is essential to obtain a high-quality organic film (organic thin film). For example, organic EL is manufactured by laminating several layers of ultrathin films of several tens of nanometers. The vapor deposition method is effective as a method for forming the organic film, and is a generally used manufacturing method. However, (1) the use efficiency of the organic material is low, (2) the organic material is easily denatured by heating, and (3) the in-plane film thickness uniformity due to the increase in area is difficult. It is considered difficult to obtain stability.

In order to solve these problems, as disclosed in Patent Documents 1 to 3, vapor deposition methods and vapor deposition apparatuses using a planar vapor deposition source having a plurality of vapor generation spots arranged two-dimensionally are known.
Japanese Patent Laid-Open No. 11-54275 JP 2002-161355 A JP 2002-302759 A

  However, in the conventional flat deposition source, the uniformity of the film thickness is maintained near the center of the required deposition area, but the phenomenon occurs that the thickness near the center is thinner than that near the center.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned unsolved problems of the prior art, and has a high use efficiency of an organic material, and a vapor deposition apparatus and a vapor deposition method capable of forming an organic film uniformly in a required vapor deposition area. Is intended to provide.

  The vapor deposition apparatus of the present invention is a vapor deposition apparatus that deposits an organic film on a substrate using a planar vapor deposition source in which a plurality of vapor generation spots are two-dimensionally arranged, and is disposed in a peripheral region of the planar vapor deposition source. Further, the arrangement density of the vapor generation spots is higher than the arrangement density of the vapor generation spots arranged in an internal region of the planar vapor deposition source.

  The vapor deposition method of the present invention includes a vapor deposition step of depositing an organic film on a substrate using a planar vapor deposition source in which a plurality of vapor generation spots are arranged two-dimensionally, and is disposed in a peripheral region of the planar vapor deposition source. Further, the amount of steam generated by the steam generating spot is larger than the amount of steam generated by the steam generating spot disposed in the internal region of the planar vapor deposition source.

  The use efficiency of the organic material when forming a large-area organic film is high, and a uniform organic film can be formed. This can greatly contribute to the cost reduction of organic EL, organic TFT, etc. and the improvement of the manufacturing process yield.

  The best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 shows a vapor deposition apparatus according to an embodiment, which has a flat vapor deposition source 10 in which a plurality of crucibles (vapor generation spots) 11 are two-dimensionally arranged, and is compared with an internal region 10 a of the flat vapor deposition source 10. Thus, the arrangement density of the crucibles 11 distributed in the peripheral region 10b is high.

  When an organic film is formed on a substrate (not shown) that is isolated from the planar vapor deposition source 10, the organic material vaporized from each crucible 11 diffuses over a wide area of the substrate. Therefore, the amount of organic matter deposited in an area corresponds to the total amount of organic matter released from the plurality of crucibles 11 in the vicinity thereof and deposited in the area. Since the thickness of the organic film has a correlation with the amount of organic matter deposited, it is important to make the amount of organic matter deposited uniform in order to obtain uniformity of the film thickness.

  However, the number of crucibles in the vicinity decreases with increasing proximity to the peripheral edge of the planar evaporation source 10. For this reason, if the crucible 11 is uniformly distributed, the amount of organic matter deposited on the periphery of the substrate is reduced, and a uniform organic film in a wide area cannot be obtained.

  Therefore, in the present embodiment, the distribution density of the crucibles 11 is distributed so that the peripheral region 10b is higher than the inner region 10a, so that the amount of organic matter deposited on the substrate is made uniform. Or you may control the quantity of the organic substance to deposit by adjusting the opening area of the crucible 11, the organic substance installation amount in each crucible 11, and vapor deposition temperature. Thereby, the uniformity of the film thickness can be obtained over a large area.

  Note that the peripheral region is a region where film thickness uniformity cannot actually be obtained, and depending on the size of the flat deposition source, it is mostly from the vapor generation spot arranged on the outermost periphery of the flat deposition source. Both show the areas where the fifth steam generation spots are arranged. Further, the inner area indicates an area inside the peripheral area. Although the arrangement density varies depending on the distance between the substrate and the opening of the vapor generation spot, it is preferable that the arrangement density in the peripheral region is 1.1 to 3.0 times higher than that in the internal region. Further, the arrangement density may be subdivided, and may gradually increase from the center toward the periphery.

  Alternatively, the opening area of the opening of each vapor generation spot may be configured so that the peripheral area is wider than the internal area. In this case, it is preferably 1.1 times to 4.0 times wider.

  In addition, in the planar vapor deposition source, an organic substance serving as a vapor deposition source may be arranged in a sheet form on a substrate provided with a heater, or a single crucible may be arranged, in order to obtain a more uniform film thickness. As described above, it is desirable to have a configuration including a plurality of crucibles and having individual heating units.

  In addition, temperature control is performed so that the amount of vapor (steam generation amount) of organic matter released by heat from a plurality of two-dimensionally arranged steam generation spots is larger in the peripheral region than in the internal region. May be. That is, the temperature at which the organic substance is released is controlled so that the peripheral region is higher than the inner region. The temperature difference in this case is not particularly limited, but is preferably set appropriately in consideration of the sublimation temperature of the organic substance to be deposited and the decomposition temperature of the organic substance.

  Moreover, although the amount of organic matter required for each vapor generation spot may be an amount of organic matter required for several depositions, it is preferable to install the amount of organic matter necessary for one deposition. In this case, it is possible to control the film thickness without having to monitor the film thickness at the time of forming the organic film by completely removing the organic matter.

  Or you may adjust the organic substance installation amount of each vapor | steam generation | occurrence | production spot so that a peripheral area may become larger compared with an internal area | region. The plurality of vapor generation spots of the flat evaporation source are preferably distributed over a wider area than the required evaporation area.

  The organic material used in the present invention is not particularly limited as long as it is an organic material that can be deposited, but the following compounds are suitable for use in organic electronic devices.

  Low molecular weight compounds such as triphenyldiamine derivatives, oxadiazole derivatives, polyphyllyl derivatives, stilbene derivatives, aluminum quinolinol derivatives, oxadiazole derivatives, triazole derivatives, phenylquinoxaline derivatives, silole derivatives, triarylamine derivatives, stilbene derivatives, poly Arylene derivatives, aromatic condensed polycyclic compounds, aromatic heterocyclic compounds, aromatic heterocondensed ring compounds, oligo or composite oligos thereof, Al complexes, Mg complexes, zinc complexes, Ir complexes, Au complexes, Ru complexes, Re complex, Os complex.

  The method of installing the organic substance in the flat evaporation source may be the organic powder as it is, but it is dissolved in an organic solvent in advance and applied by spin coating, spraying, dip coating, dispenser, ink jet or the like. Alternatively, a method of removing the organic solvent may be used. From the viewpoint that an accurate amount can be set, the dispenser method and the ink jet method are particularly effective.

  The heating part of each steam generation spot may be arranged at the lower part or upper part of the installed organic matter, both at the lower part and the upper part, but in order to avoid clogging of the opening part of the steam generation spot, etc. Is preferably disposed at least in the upper part and has a through hole. Moreover, you may equip the upper part of a heating part with the radiant heat prevention means.

  A planar evaporation source 20 shown in FIG. 2 is used. The plurality of vapor generation spots 21 of the flat evaporation source 20 are distributed so that the arrangement density is higher in the peripheral region 20b than in the internal region 20a. The planar vapor deposition source 20 of this example has the internal configuration shown in FIG. 3, and the manufacturing process thereof is as follows.

On the quartz substrate 31 serving as the base of the planar vapor deposition source 20, a total of 25 cylindrical depressions 31a having a diameter of 2.0 mm and a depth of 0.2 mm are provided at a pitch of 5.0 mm in the inner region 20a and in the peripheral region 20b. A total of 64 pieces are produced at a pitch of 4.0 mm. Next, carbon is deposited to a thickness of 100 nm on the substrate surface by sputtering. Next, 1 μl of 0.5 g / l tetrahydrofuran (THF) solution of tris (8-hydroxyquinoline) aluminum (Alq ₃ ) was applied to each recess 31a, and THF was completely removed by heating under reduced pressure. An organic substance 32 is obtained. Next, a molybdenum sheet 33 having a thickness of 50 μm in which a through hole 33a having a diameter of 0.3 mm is disposed on the upper portion of each recess 31a is disposed.

  A 1.0 mm thick quartz substrate 34 having a funnel-shaped opening 34a (wide mouth: diameter 2.0 mm, narrow mouth: diameter 1.0 mm) is disposed thereon. Next, a 40 mm square glass substrate (not shown) on which the organic film is to be formed is placed on an upper part separated from the molybdenum sheet 33 by 6.0 mm.

  The molybdenum sheet 33 is energized, and vacuum deposition is performed until the organic matter 32 is completely removed by resistance heating. The film thickness of the obtained organic film is measured at 100 locations at a pitch of 4 mm using an interference film thickness meter. As an index of film thickness uniformity, the uniformity coefficient A = (film thickness average value at 64 locations in the peripheral region) / (film thickness average value at 36 locations in the inner region) is calculated. This process was repeated 10 times, and the uniformity coefficient A was determined. As a result, 0.95 or more was obtained.

(Comparative Example 1)
An organic film is formed by the same method as in Example 1 except that a total of 100 recesses on the quartz substrate are prepared with a pitch of 4.0 mm, and the film thickness is measured by the same method as in Example 1. This process was repeated 10 times, and the uniformity coefficient A was found to be 0.80 to 0.90.

  The planar vapor deposition source 20 shown in FIG. 2 was produced as follows with the internal configuration shown in FIG.

A total of 25 hemispherical depressions 41a having a diameter of 3.0 mm and a depth of 0.5 mm are provided on the molybdenum substrate 41 serving as the base of the flat evaporation source 20 in the inner region 20a at a pitch of 5.0 mm, and in the peripheral region 20b. A total of 64 pieces are produced at a pitch of 4.0 mm. 1 μl of a 0.5 g / l THF solution of Alq ₃ is applied to each recess 41 a, and THF is completely removed by heating under reduced pressure to obtain an organic substance 42. Next, a molybdenum sheet 43 having a thickness of 50 μm in which a through hole 43a having a diameter of 0.3 mm is arranged on the upper portion of each recess 41a is disposed.

  A 1.0 mm thick quartz substrate 44 having a funnel-shaped opening 44a (wide mouth: diameter 2.0 mm, narrow mouth: diameter 1.0 mm) is disposed thereon. Next, a 40 mm square glass substrate (not shown) on which the organic film is to be formed is placed on an upper part separated from the molybdenum sheet 43 by 6.0 mm.

  The molybdenum substrate 41 and the molybdenum sheet 43 are energized, and vacuum deposition is performed until the organic matter 42 is completely blown off by resistance heating. The thickness of the obtained organic film is measured by the same method as in Example 1. This process was repeated 10 times, and the uniformity coefficient A was determined. As a result, 0.95 or more was obtained.

(Comparative Example 2)
An organic film is formed by the same method as in Example 2 except that a total of 100 recesses on the molybdenum substrate are formed at 4.0 mm, and the film thickness is measured by the same method as in Example 1. This process was repeated 10 times, and the uniformity coefficient A was found to be 0.80 to 0.90.

  As shown in FIG. 5, the planar vapor deposition source 50 in which the vapor generation spots 51 are uniformly distributed in the inner region 50a and the peripheral region 50b is manufactured by the following steps.

A total of 100 columnar depressions having a diameter of 3.0 mm and a depth of 0.3 mm are formed on a quartz substrate at a pitch of 4.0 mm. Next, carbon is deposited to a thickness of 100 nm on the substrate surface by sputtering. Apply 5 μl of an Alq ₃ 1.0 g / l THF solution to each recess and remove the THF completely by heating under reduced pressure. Next, a through hole having a diameter of 0.3 mm is formed above the recess of the inner region 50a, and a through hole having a diameter of 0.5 mm having a larger opening area than the through hole of the inner region 50a is formed above the recess of the peripheral region 50b. A molybdenum sheet having a thickness of 50 μm is disposed.

  A quartz substrate having a thickness of 1.0 mm having a funnel-shaped opening (wide mouth: diameter 2.0 mm, narrow mouth: diameter 1.0 mm) is disposed thereon. Next, a 40 mm square glass substrate (not shown) on which the organic film is to be formed is placed on an upper part separated from the molybdenum sheet by 6.0 mm.

  Energize the molybdenum sheet and perform vacuum deposition for several minutes by resistance heating. The thickness of the obtained organic film is measured by the same method as in Example 1. This process was repeated 10 times, and the uniformity coefficient A was determined. As a result, 0.90 or more was obtained.

(Comparative Example 3)
An organic film is formed by the same method as in Example 3 except that all through holes arranged in the upper part of the recess have a diameter of 0.3 mm, and the film thickness is measured by the same method as in Example 1. This operation was repeated 10 times, and the uniformity coefficient A was determined to be 0.75 to 0.85.

  The flat vapor deposition source 50 shown in FIG. 5 is produced by the following steps.

A total of 100 columnar depressions having a diameter of 3.0 mm and a depth of 0.3 mm are formed on a quartz substrate at a pitch of 4.0 mm. Next, carbon is deposited to a thickness of 100 nm on the substrate surface by sputtering. Apply 5 μl of an Alq ₃ 1.0 g / l THF solution to each recess and remove the THF completely by heating under reduced pressure. Next, in the inner region 50a, a molybdenum sheet having a thickness of 50 μm in which a through hole having a diameter of 0.3 mm is provided in the upper portion of the recess is disposed. Further, in the peripheral region 50b, a tungsten sheet having a thickness of 50 μm in which a through hole having a diameter of 0.3 mm is provided in the upper part of the recess is disposed.

  A quartz substrate having a thickness of 1.0 mm having a funnel-shaped opening (wide mouth: diameter 2.0 mm, narrow mouth: diameter 1.0 mm) is disposed thereon. Next, a 40 mm square glass substrate (not shown) on which the organic film is to be formed is placed on an upper part separated from each metal sheet by 6.0 mm. Next, the molybdenum sheet and the tungsten sheet are energized independently, and vacuum deposition is performed for several minutes by resistance heating. At this time, the current value is set so that the heat generation amount of the tungsten sheet is increased. The thickness of the obtained organic film is measured by the same method as in Example 1. This process was repeated 10 times, and the uniformity coefficient A was determined. As a result, 0.95 or more was obtained.

(Comparative Example 4)
An organic film is formed by the same method as in Example 3 except that energization is performed so that the calorific values of the molybdenum sheet and the tungsten sheet are equal during vacuum deposition, and the film thickness is measured by the same method as in Example 1. This operation was repeated 10 times, and the uniformity coefficient A was determined to be 0.75 to 0.85.

  The flat vapor deposition source 50 shown in FIG. 5 is produced by the following steps.

A total of 100 cylindrical depressions having a diameter of 2.0 mm and a depth of 0.2 mm are formed on a quartz substrate at a pitch of 4.0 mm. Next, carbon is deposited to a thickness of 100 nm on the substrate surface by sputtering. 1 μl of Alq ₃ 0.5 g / l THF solution is applied to the recess in the inner region 50a and 1.2 μl in the recess in the peripheral region 50b, and the THF is completely removed by heating under reduced pressure. Next, a 50 μm thick tungsten sheet having a through hole having a diameter of 0.3 mm is disposed on the upper part of the recess.

  A quartz substrate having a thickness of 1.0 mm having a funnel-shaped opening (wide mouth: diameter 2.0 mm, narrow mouth: diameter 1.0 mm) is disposed thereon. Next, a 40 mm square glass substrate (not shown) on which the organic film is to be formed is disposed on the upper portion of 6.0 mm from the tungsten sheet. Next, the tungsten sheet is energized, and vacuum deposition is performed until the organic matter is completely removed by resistance heating. The thickness of the obtained organic film is measured by the same method as in Example 1. This process was repeated 10 times, and the uniformity coefficient A was determined. As a result, 0.95 or more was obtained.

(Comparative Example 5)
An organic film is formed by the same method as in Example 5 except that 1 μl of all THF solutions of Alq ₃ 0.5 g / l placed in the depression is formed, and the film thickness is measured by the same method as in Example 1. This operation was repeated 10 times, and the uniformity coefficient A was found to be 0.80 to 0.90.

It is a perspective view which shows the plane vapor deposition source by one embodiment. It is a top view which shows the planar vapor deposition source by Example 1 and Example 2. FIG. 5 is a diagram illustrating a production process of a planar vapor deposition source according to Example 1. FIG. 6 is a diagram for explaining a production process of a planar vapor deposition source according to Example 2. FIG. It is a top view which shows the planar vapor deposition source by Example 3 thru | or Example 5. FIG.

Explanation of symbols

10, 20, 50 Planar deposition source 10a, 20a, 50a Internal region 10b, 20b, 50b Peripheral region 11 Crucible 21, 51 Steam generation spot

Claims (6)

  A vapor deposition apparatus for depositing an organic film on a substrate using a planar vapor deposition source in which a plurality of vapor generation spots are two-dimensionally arranged, and the arrangement of the vapor generation spots disposed in a peripheral region of the planar vapor deposition source The vapor deposition apparatus, wherein a density is higher than an arrangement density of the vapor generation spots arranged in an internal region of the planar vapor deposition source.   A vapor deposition apparatus for depositing an organic film on a substrate using a planar vapor deposition source in which a plurality of vapor generation spots are two-dimensionally arranged, wherein an opening of the vapor generation spot disposed in a peripheral region of the planar vapor deposition source The vapor deposition apparatus characterized in that an area is larger than an opening area of the vapor generation spot disposed in an internal region of the planar vapor deposition source.   The vapor deposition apparatus according to claim 1, wherein the plurality of vapor generation spots are a plurality of crucibles. A vapor deposition step of depositing an organic film on a substrate using a planar vapor deposition source in which a plurality of vapor generation spots are two-dimensionally arranged;
The amount of steam generated by the steam generation spot disposed in the peripheral region of the planar deposition source is greater than the amount of steam generated by the steam generation spot disposed in the inner region of the planar deposition source. Deposition method.   The vapor deposition method according to claim 4, wherein the vapor generation spot disposed in the peripheral region is controlled to a temperature higher than that of the vapor generation spot disposed in the internal region.   The vapor deposition method according to claim 4, wherein an installation amount of the organic substance in the vapor generation spot arranged in the peripheral region is larger than an installation amount of the organic substance in the vapor generation spot arranged in the internal region.

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