JP4303814B2 - Organic EL device manufacturing apparatus and manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for manufacturing an organic thin film such as a constituent thin film of an organic EL element, and a manufacturing method, and more specifically, an organic material is evaporated by heating and deposited in a film formation region on a substrate. The present invention relates to an organic thin film manufacturing apparatus using a vapor deposition method and a manufacturing method.
[0002]
[Prior art]
A vacuum deposition method is known as one of basic techniques for forming a thin film. In this vacuum deposition method, a thin film is formed by appropriately combining an evaporation source and a deposition substrate in a vacuum chamber. Various means for creating the evaporation source have been considered. For example, a metal container having a relatively high electrical resistance as described in Applied.Physics.Letter.Vol.68, No.16,15 April 1996 P2276-2278. A so-called resistance heating vapor deposition method is known in which an electric current is passed through a (metal boat) and the raw material is evaporated by the generated heat. In addition, a so-called electron beam / laser beam vapor deposition method is also known in which a raw material is directly irradiated with an electron beam or a laser beam, and the raw material is evaporated with the energy. Among them, a film forming method using resistance heating (resistance heating vapor deposition method) is widely used because the structure of the manufacturing apparatus is simple and a high-quality thin film can be formed at low cost.
[0003]
In the resistance heating vapor deposition method, a metal material such as tungsten, tantalum, or molybdenum having a high melting point is processed into a thin plate shape, and a raw material container (metal boat) is produced from a metal plate having high electrical resistance, and a direct current is applied from both ends thereof. The raw material is evaporated using the generated heat, and the evaporation gas is supplied. Part of the evolved gas is deposited on the substrate, forming a thin film.
[0004]
By the way, in these vapor deposition methods, a method of using a mask or the like is generally used when several types of organic thin films are formed on a single substrate in separate regions or only on specific regions. However, it is difficult to apply a fine pattern by mask vapor deposition. In addition, in an ordinary vapor deposition method or the like, an expensive organic material is deposited on a relatively large mask portion, which is inefficient and economically problematic.
[0005]
In recent years, organic EL elements have been actively studied. This is because a hole transport material such as triphenyldiamine (TPD) is deposited on the hole injection electrode as a thin film, a fluorescent material such as an aluminum quinolinol complex (Alq3) is laminated as a light emitting layer, and a work function such as Mg is further formed. An element having a basic structure in which a small metal electrode (electron injection electrode) is formed, and several hundreds to several tens of thousand cd / m at a voltage of about 10V.² It is attracting attention because of its extremely high brightness.
[0006]
Conventionally, when manufacturing a product to which an organic EL element is applied, a functional thin film made of an organic material is formed using the vapor deposition method as described above. In such a mass production process, productivity is high and how to improve the use efficiency of materials is an important issue. However, the manufacturing apparatus using the conventional vapor deposition apparatus has poor use efficiency of materials, wastes expensive organic materials, and complicated painting work when trying to obtain RGB full-color display, It was difficult to increase the color separation accuracy.
[0007]
[Problems to be solved by the invention]
The object of the present invention is to enable stable deposition for a long time using an evaporation source capable of supplying a continuous material, and to easily separate the organic thin film, and to provide a mixture or a doped organic material. It is also possible to realize an organic thin film manufacturing apparatus and a manufacturing method that can cope with vapor deposition at a relatively low temperature.
[0008]
[Means for Solving the Problems]
  The above-mentioned purpose is as follows (1) to (6).
  (1)Organic EL element component filmA raw material supply source for supplying a raw material solution in which an organic material is dissolved in a solvent;
  A supply amount adjusting means for adjusting and supplying the raw material solution from the raw material supply source to a certain amount;
  A raw material vaporization means for vaporizing the supplied raw material solution,
  The raw material vaporization means includes:A vaporization container formed in a container shape having a predetermined capacity, and in the vaporization containerHeating means for heating the supplied raw material solution to a temperature higher than the vaporization temperature of the organic materialAnd formed in the vaporization container,For supplying the raw material to the film formation surfaceAnd vaporizing the raw material solution supplied by heating the vaporization container to a temperature higher than the vaporization temperature of the organic material by the heating means, and the raw material vaporized by the increase in the vaporization container internal pressure due to the vaporization from the opening Release and deposit on the film forming surface to form the organic EL element constituent filmOrganicEL elementManufacturing equipment.
  (2)The organic EL element manufacturing apparatus according to (1), wherein a substrate having a film formation surface is disposed on the vaporization container, and the opening is formed at a position corresponding to the film formation surface of the substrate.
  (3The above-mentioned having an alignment adjustment mechanism for the substrate(2)OrganicEL elementManufacturing equipment.
  (4) The supply amount adjusting means is an organic material according to any one of (1) to (3), wherein the flow rate of the raw material solution is controlled by a mass flow control method.EL elementManufacturing equipment.
  (5)An adjustment step of adjusting the raw material solution in which the organic material of the organic EL element constituent film is dissolved in a solvent to a certain amount;
  A supply step of supplying the adjusted raw material solution to the vaporization container formed in a container shape having a predetermined capacity;
  A vaporization step of vaporizing the supplied raw material solution,
  In the vaporization step, the vaporization container is heated to a temperature higher than the vaporization temperature of the organic material, the supplied raw material solution is vaporized, and the vaporized raw material is formed in the vaporization container by increasing the internal pressure of the vaporization container due to vaporization. A method for manufacturing an organic EL element, wherein the organic EL element is formed by discharging from an opening for supplying to the film formation surface and depositing on the film formation surface.
  (6)The manufacturing method of the organic EL element according to (5), wherein the adjustment process, the supply process, and the vaporization process are executed for each type of the organic EL element constituent film.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The apparatus for producing an organic thin film of the present invention includes a raw material supply source that supplies a raw material solution in which an organic material is dissolved in a solvent, a supply amount adjusting unit that adjusts the raw material solution from the raw material supply source to a certain amount, A raw material vaporization means for vaporizing the supplied raw material solution, and the raw material vaporization means has a heating means for heating the supplied raw material solution to a temperature higher than the vaporization temperature of the solvent, and emits the vaporized raw material. It has an opening for making it.
[0010]
In this way, the organic material to be formed is dissolved in a solvent, the raw material solution is adjusted to a predetermined flow rate, supplied, heated to vaporize, and formed into a film, thereby adjusting the supply amount of the raw material. The film composition and film thickness can be adjusted accurately, and continuous film formation is possible.
[0011]
The raw material supply source holds the raw material solution dissolved in the organic solvent and supplies it as necessary. Such a raw material supply source may be a container, a tank, or the like that can store a predetermined amount of the raw material solution. The shape and size are not particularly limited, and may have an appropriate capacity and shape as necessary. Further, the material is not particularly limited, but it is necessary that the material does not dissolve or corrode in an organic solvent and is not a substance that reacts and bonds with a raw material organic material.
[0012]
The raw material solution held in the raw material supply source is obtained by dissolving an organic material as a raw material in an organic solvent. By dissolving the organic material in the solvent, the deposition rate can be controlled by controlling the flow rate, and the deposition rate can be controlled with high accuracy without directly controlling the deposition rate (temperature).
[0013]
The organic material used as a raw material is not particularly limited as long as it can be formed into a film by a vapor deposition method, and various organic materials can be used. For example, π-electron conjugated organic semiconductor substances such as chain polymers such as polyacetylene and polyin, or molecular crystals of polyacenes (such as anthracene) and metal chelate compounds (such as copper phthalocyanine), anthracene, diethylamines, p-phenylenediamine, Compounds such as tetramethyl-p-phenylenediamine (TMPD) and tetrathiofulvalene (TTF) and acceptors such as tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE) and p-chloroanil Examples thereof include charge transfer complexes composed of compounds and the like, dye materials, fluorescent materials, liquid crystal materials, and the like.
[0014]
The vaporization temperature of these organic materials is preferably about 200 to 500 ° C., particularly about 300 to 400 ° C. under atmospheric pressure during film formation. Moreover, when using 2 or more types of materials, it is necessary to heat more than the highest vaporization temperature. Moreover, it is necessary to heat at the decomposition temperature of the material used. The concentration of the organic material in the solvent is preferably about 0.1 to 50 wt%, particularly about 5 to 20 wt%.
[0015]
Among these organic materials, the organic material of the organic EL element constituent film is preferable. The constituent films of the organic EL element are a hole injecting and transporting layer, a light emitting layer, an electron injecting and transporting layer, and the like. These constituent thin films, particularly the light emitting layer, require precise film thickness and composition control. Therefore, by using the apparatus of the present invention, it is possible to accurately control the film thickness and the composition, and to improve and stabilize the quality of the organic EL element, and to provide a new element having further excellent performance. It becomes possible.
[0016]
Examples of the organic substance used for the light emitting layer of the organic EL element include a fluorescent substance that is a compound having a light emitting function. Examples of such a fluorescent substance include at least one selected from compounds such as those disclosed in JP-A 63-264692, such as quinacridone, rubrene, and styryl dyes. Further, quinoline derivatives such as metal complex dyes having 8-quinolinol or a derivative thereof such as tris (8-quinolinolato) aluminum as a ligand, tetraphenylbutadiene, anthracene, perylene, coronene, 12-phthaloperinone derivatives, and the like can be given. Further, phenyl anthracene derivatives described in JP-A-8-12600 (Japanese Patent Application No. 6-110568), tetraarylethene derivatives described in JP-A-8-12969 (Japanese Patent Application No. 6-114456), and the like are used. be able to.
[0017]
In addition, a host material capable of emitting light by itself and a dopant may be used in combination. Thereby, the light emission wavelength characteristic of the host material can be changed, light emission shifted to a long wavelength can be achieved, and the light emission efficiency and stability of the device are improved. In such a case, the content of the compound in the light emitting layer is preferably 0.01 to 20% by volume, more preferably 0.1 to 15% by volume.
[0018]
As the host substance, a quinolinolato complex is preferable, and an aluminum complex having 8-quinolinol or a derivative thereof as a ligand is more preferable. Examples of such aluminum complexes are those disclosed in JP-A-63-264692, JP-A-3-255190, JP-A-5-70733, JP-A-5-258859, JP-A-6-215874, and the like. Can be mentioned.
[0019]
Specifically, first, tris (8-quinolinolato) aluminum, bis (8-quinolinolato) magnesium, bis (benzo {f} -8-quinolinolato) zinc, bis (2-methyl-8-quinolinolato) aluminum oxide, tris (8-quinolinolato) indium, tris (5-methyl-8-quinolinolato) aluminum, 8-quinolinolatolithium, tris (5-chloro-8-quinolinolato) gallium, bis (5-chloro-8-quinolinolato) calcium, 5,7-dichloro-8-quinolinolato aluminum, tris (5,7-dibromo-8-hydroxyquinolinolato) aluminum, poly [zinc (II) -bis (8-hydroxy-5-quinolinyl) methane], etc. There is.
[0020]
Other host materials include phenyl anthracene derivatives described in JP-A-8-12600 (Japanese Patent Application No. 6-110568) and JP-A-8-12969 (Japanese Patent Application No. 6-114456). Tetraarylethene derivatives and the like are also preferable.
[0021]
The light emitting layer is preferably a mixed layer of at least one hole injecting / transporting compound and at least one electron injecting / transporting compound, if necessary, and further contains a dopant in the mixed layer. It is preferable to make it. The content of the compound in such a mixed layer is preferably 0.01 to 20% by volume, more preferably 0.1 to 15% by volume.
[0022]
The hole injecting and transporting compound and the electron injecting and transporting compound used for the mixed layer may be selected from a hole injecting and transporting compound and an electron injecting and transporting compound described later, respectively. Among them, as the hole injecting and transporting compound, it is preferable to use an amine derivative having strong fluorescence, for example, a triphenyldiamine derivative that is a hole transporting material, a styrylamine derivative, or an amine derivative having an aromatic condensed ring. .
[0023]
As the electron injecting and transporting compound, it is preferable to use a quinoline derivative, a metal complex having 8-quinolinol or a derivative thereof as a ligand, particularly tris (8-quinolinolato) aluminum (Alq3). Moreover, it is also preferable to use the above phenylanthracene derivatives and tetraarylethene derivatives.
[0024]
The mixing ratio in this case depends on the carrier mobility and carrier concentration of each, but generally the weight ratio of the compound having a hole injecting and transporting compound / the compound having an electron injecting and transporting function is 1/99 to 99/1. It is more preferable that the ratio is about 10/90 to 90/10, particularly preferably about 20/80 to 80/20.
[0025]
In addition, the thickness of the mixed layer is preferably equal to or greater than the thickness corresponding to one molecular layer and less than the thickness of the organic compound layer. Specifically, it is preferably 1 to 85 nm, more preferably 5 to 60 nm, and particularly preferably 5 to 50 nm.
[0026]
Examples of the hole injecting and transporting layer include JP-A 63-295695, JP-A 2-191694, JP-A 3-792, JP-A-5-234681, JP-A-5-239455, Various organic compounds described in JP-A-5-299174, JP-A-7-126225, JP-A-7-126226, JP-A-8-100192, EP0650955A1, and the like can be used. For example, tetraarylbenzidine compounds (triaryldiamine or triphenyldiamine: TPD), aromatic tertiary amines, hydrazone derivatives, carbazole derivatives, triazole derivatives, imidazole derivatives, oxadiazole derivatives having amino groups, polythiophenes, etc. . These compounds may be used alone or in combination of two or more. When two or more types are used in combination, they may be laminated as separate layers or mixed.
[0027]
The electron injecting and transporting layer includes a quinoline derivative such as an organometallic complex having 8-quinolinol or a derivative thereof such as tris (8-quinolinolato) aluminum (Alq3) as a ligand, an oxadiazole derivative, a perylene derivative, a pyridine derivative, Pyrimidine derivatives, quinoxaline derivatives, diphenylquinone derivatives, nitro-substituted fluorene derivatives, and the like can be used.
[0028]
As the solvent for dissolving the organic material, an organic solvent is preferable, and an optimum solvent may be used depending on the type of the organic material to be dissolved. It is necessary that the material does not dissolve or corrode the constituent material of the raw material supply source or the constituent material of the flow path. The boiling point is preferably 50 to 150 ° C, particularly about 60 to 100 ° C. Specifically, tetrahydrofuran (THF) and the like are preferable.
[0029]
The raw material supply means has a transport means for transporting the raw material solution in addition to a container for holding the raw material solution. This conveying means can be used by appropriately selecting from known means used for moving the liquid. Specifically, there may be mentioned a method in which a mechanical pressure such as a liquid pump is applied for conveyance, a pressure is applied to the raw material solution by a gas such as air or an inert gas, and a method for conveyance with this is used. Among these, those using gas pressure are suitable for accurate flow rate adjustment. Examples of gases used for transportation include air, inert gases such as Ar, Ne, Xe, and Kr, N₂ Among these, N₂ Etc. are preferred.
[0030]
The pump that is used as necessary is not particularly limited as long as the fluid can be delivered at a predetermined pressure. However, a pump that does not dissolve in an organic solvent or change in quality due to this is preferable. Specifically, a centrifugal pump, a bellows pump, a roller pump, or the like can be used.
[0031]
The supply amount adjusting means adjusts the supply amount of the raw material solution to be supplied so as to obtain an optimum supply amount. The supply amount adjusting means may be any one having a function of sending and conveying the raw material solution by itself, or adjusting the flow rate of the raw material solution supplied from the raw material supplying means in advance. However, it is preferable that the flow rate can be accurately adjusted. Since the deposition rate is controlled by controlling the flow rate of the liquid, accurate and stable deposition can be performed for a long time. That is, in a conventional vapor deposition apparatus that controls the vapor deposition rate by charging the raw material for vapor deposition into a crucible and the like and controlling the heating of this crucible, it was difficult to perform accurate and stable vapor deposition for a long time. In the apparatus of the present invention, the deposition control can be performed by an accurate and stable control method of liquid flow rate control.
[0032]
Specifically, it may be controlled by a control method such as a mass flow control system using a variable flow rate adjusting valve and a flow meter. As the flow meter, a mass flow meter is preferable, but a differential pressure flow meter, an area flow meter, a volumetric flow meter, an electromagnetic flow meter, a turbine flow meter, a vortex flow meter, and the like can be used as necessary.
[0033]
The flow rate of the raw material solution adjusted by the supply amount adjusting means is not particularly limited, but it is usually preferably 0.5 to 100 ml / min, particularly preferably about 10 to 50 ml / min. As the accuracy of the controllable flow rate, one that can be adjusted in a range of ± 0.5% or less, and ± 0.2% or less is preferable.
[0034]
The raw material vaporization means heats and vaporizes the supplied raw material solution, and then discharges and diverges it through an opening having a predetermined size in order to supply it to the film formation surface. That is, normally, the raw material vaporization means has a closed container shape having a predetermined capacity, and has an opening for discharging the raw material at the upper part thereof, and the raw material gas discharged from this opening is formed on the substrate or the like. Adheres to and deposits on the film surface.
[0035]
As heating means for heating and vaporizing the raw material solution, various known heating means can be used. For example, what is necessary is just to have predetermined heat capacity, reactivity, etc., for example, a tantalum wire heater, a sheath heater, etc. are mentioned. The heating temperature by the heating means is preferably about 100 to 1400 ° C., and the accuracy of temperature control varies depending on the material to be evaporated, but is preferably about ± 5 ° C. or less at 400 ° C., for example.
[0036]
Vaporized source gas is released / diverged from the opening due to an increase in the internal pressure of the raw material vaporization means due to vaporization of the raw material solution, and is deposited on the film formation surface of a substrate or the like arranged at a predetermined distance from the opening. To do.
[0037]
The opening is usually a small hole that matches the shape of the film formation region, and may be, for example, a square, a circle, an ellipse, or a slit. The size of the opening can be varied depending on the material, shape, and film formation region. Usually, the diameter is preferably about 10 μm to 1 mm in terms of a circle. The distance from the upper end surface of the opening to the film formation surface is preferably 0 to 1 mm.
[0038]
Therefore, when forming a film over a wide range or when forming a film in a specific region, an opening may be formed in a necessary portion. In the case of separate coating, a mechanism for adjusting the alignment between the film formation region and the opening may be provided. Specifically, the alignment may be adjusted by placing the substrate on the XY table and operating the XY table. These controls can be easily performed by a control device equipped with a processor such as a microcomputer. The accuracy of the alignment adjustment mechanism is preferably ± 10 μm or less. An XY table is usually composed of a movable support (linear bearing or the like) having a degree of freedom in the XY axis direction, a pulse motor, a servo motor, or the like that drives the table in each of the XY directions. ing.
[0039]
When performing separate coating, among the above components, a plurality of raw material supply sources, supply amount adjusting means, and raw material vaporization means may be prepared, and different organic materials may be formed. In this case, one film forming chamber may be prepared for each apparatus.
[0040]
Next, the present invention will be described more specifically based on the drawings.
[0041]
FIG. 1 is a schematic configuration diagram showing a basic configuration of a film forming apparatus of the present invention. In the figure, the organic thin film production apparatus of the present invention comprises a raw material storage tank 2 as a raw material supply means, a mass flow controller 3 as a supply amount adjustment means, a vaporization container 4 as a raw material vaporization means, and an organic thin film. And a substrate 5 to be filmed. Further, the vaporization container 4 and the substrate 5 are disposed in the film forming chamber 8 so as to be able to form a film in a predetermined atmosphere (degree of vacuum) while being shielded from the external atmosphere. An exhaust device 9 is connected to the film forming chamber 8 via a duct 14 so that the inside of the film forming chamber 8 can be maintained at a predetermined degree of vacuum (depressurized atmosphere) during film formation.
[0042]
The raw material storage tank 2 is filled with N via a gas flow path 11.₂ A predetermined amount of a carrier gas such as is supplied. The gas flow path 11 is not particularly limited as long as it can carry a necessary amount of gas, and may be pipe-shaped, hose-shaped, or duct-shaped. As the material, a material conventionally used for transporting liquid (organic solvent) can be used, and preferably a metal material such as stainless steel, copper, aluminum or the like can be used.
[0043]
A raw material solution 1 is stored in the raw material storage tank 2, and when a transfer gas is introduced from the gas flow path 11, the pressure is transferred to the mass flow controller 3 through the raw material flow path 12. The mass flow controller includes a mass flow meter. This mass flow meter has a basic configuration as shown in FIG. 2, for example.
[0044]
FIG. 2 is a partial cross-sectional schematic view of the mass flow controller 3. In the figure, there are a main flow path 301 and a sub flow path 302 that are connected to the raw material flow paths 12 and 13 inside the mass flow controller. Assuming that the raw material solution flows from the direction of the arrow, a raw material solution flow that flows in the sub-channel 304 is generated in addition to the raw material solution flow that flows in the main channel 301. Two coils L1 and L2 are wound around the sub-channel 304, and are connected to both ends of resistors R1 and R2 of a bridge circuit constituted by resistors R1, R2, R3 and R4, respectively. This bridge circuit is set to be balanced under a predetermined condition (initial state, steady state, etc.) by the variable resistor R3. The coils L1 and L2 are heated with a predetermined calorific value by a current source (not shown).
[0045]
Here, when the raw material solution flows in the sub-channel 304 when the bridge circuit is in an equilibrium state, a temperature difference is generated between the coils L1 and L2. This temperature difference appears as a difference between the resistance values of the coils L1 and L2, the balance of the bridge circuit is lost, and a potential difference is generated between the input terminals of the amplifier Amp. This potential difference is proportional to the flow rate of the raw material solution flowing through the sub flow channel 304. Since the raw material solution flows at a predetermined flow rate ratio between the sub flow channel 304 and the main flow channel 301, the entire flow rate and its change are input to the amplifier Amp. This can be grasped from the potential difference applied between the terminals. The flow rate information is amplified by an amplifier Amp and is given to the control device 305 of the movable valve 302. The control device 305 controls the movable shaft 303 based on the flow rate information given from the amplifier Amp, adjusts the opening degree of the movable valve 302, and controls the raw material solution flowing in the main channel 301 to have a predetermined flow rate. . In this way, the mass flow controller 3 can perform accurate flow control. In the above example, the case where the bridge circuit is in an equilibrium state has been described as a reference. However, the present invention is not necessarily limited to this, and a state having a predetermined potential difference may be used as a reference.
[0046]
The raw material solution adjusted to an accurate flow rate by the mass flow controller 3 is transported, introduced, and vaporized into the evaporation container 4 via the raw material flow path 13. At this time, since the exhaust port 4 b is formed in the evaporation container 4, the internal atmosphere is always exhausted so as to be the same as that of the film forming chamber 8. The vaporized raw material vapor is heated and vaporized in a predetermined reduced pressure atmosphere, and is deposited on the substrate 5 so as to be emitted in the direction of the opening 4a and discharged from the opening 4a.
[0047]
A more detailed configuration example of the vaporization container 4 is shown in FIG. The illustrated vaporizing container 4 includes a container main body 42, a heater 44 formed in close contact with the container main body 42, and an outer jacket 43 formed so as to cover them. In addition, an upper lid 41 having a plurality of openings 4 a is disposed in close contact with the container main body 42, and a space for evaporating the raw material solution is formed in the vaporization container 4. Further, the exhaust port 4 b is formed in the vaporization container 4.
[0048]
The material constituting the container body 42 is not particularly limited as long as it can withstand a predetermined temperature and does not react with an organic solvent or an organic material. Specifically, what is used as a material for the crucible is preferable, and examples thereof include pyrolytic boron nitride (PBN), ceramics such as alumina, quartz, and metals such as tungsten, tantalum, and molybdenum. Particularly, metal is preferable in consideration of workability for forming the opening. The size of the container main body may be an optimum size depending on the size of the substrate to be vapor-deposited, the solvent to be used, the raw material, and the like, but it is usually formed according to the size of the substrate to be deposited. The shape may be a cylindrical shape or a square box shape, but is usually a square box shape along the substrate shape.
[0049]
The heater 44 is not particularly limited as long as it can heat the container body to a predetermined temperature, and is not necessarily formed in close contact with the container body. For example, a tantalum wire heater, a sheath heater, etc. may be mentioned, and a graphite thin film may be directly formed on the container body, or a film heater combining polyimide and stainless steel foil may be attached.
[0050]
The outer jacket 43 is not particularly limited as long as it has a predetermined strength and corrosion resistance, and may be selected from those similar to the container main body 42. For example, molybdenum or the like is preferably used. Can do. Moreover, you may use together heat insulating materials, such as molybdenum, a tantalum, stainless steel (SUS316), Inconel, cow wool, asbestos, etc. which have heat reflectivity, heat resistance, corrosion resistance, etc. as needed.
[0051]
In FIG. 3, the substrate 5 is in close contact with the vaporization container 4. The raw material solution supplied from the raw material flow path 13 at a predetermined flow rate is heated by the heater 44 and evaporated. At this time, since the internal gas is exhausted from the exhaust port 4b as shown by the arrow a, the evaporated solvent gas is exhausted from the exhaust port 4b, and the vaporized organic material is the opening 4a as shown by the arrow b. In the direction of the upper lid 41 with a gap, the film is discharged from the opening 4 a and is formed on the substrate 5.
[0052]
The heater 44 of the vaporization container 4 is connected to the heating control device 7 and is heated and controlled by electric power (current) supplied from the heating control device 7. The heating control device 7 has temperature detection means 6 disposed in the vaporization container 4, and controls the electric power (current) applied to the heater 44 according to the temperature information of the vaporization container given from the temperature detection means 6. .
[0053]
The heating control device 7 can be configured by a general-purpose microprocessor (MPU) as a control unit and a control algorithm on a storage medium (ROM, RAM, etc.) connected to the MPU. Also, it can be used regardless of the processor mode such as CISC, RISC, DSP, etc., and can also be configured by an analog operation circuit using an operational amplifier or the like, or a combination of logic circuits such as ASIC or general IC. . Then, a power (current) control unit including semiconductor elements such as bipolar transistors, MOS-FETs, triacs, UJTs, and SCRs may be controlled by a control signal from the control unit.
[0054]
The temperature control method is not particularly limited as long as the temperature control can be appropriately performed. For example, hardware (analog, digital circuit) or a PID (proportional integral derivative) control method is applied. A control algorithm or the like developed from
[0055]
The temperature detection means 6 may be any means as long as it can appropriately detect the temperature of the raw material vaporization means, and examples thereof include a thermocouple such as platinum-platinum rhodium and tungsten-tungsten rhenium.
[0056]
The atmosphere during film formation in the film formation chamber is usually a vacuum state. The pressure during film formation is preferably 1 × 10^-8~ 1x10^-FiveIn Torr, the heating temperature is higher than the vaporization temperature of the organic material, and is usually 200 to 500 ° C., particularly preferably about 300 to 450 ° C.
[0057]
Of the above components, the raw material supply source is mainly composed of a transport gas supplied from the raw material storage tank 2 and the transport path 11, and the supply amount adjusting means is mainly composed of the mass flow controller 3. The raw material vaporization means is mainly constituted by the evaporation container 4. The heating means of the raw material vaporization means is mainly composed of the heater 44 of the raw material container 4, the temperature detection means 6 and the heating control device 7.
[0058]
【Example】
A film forming apparatus having the configuration shown in FIGS. 1 to 3 was prepared, and an organic thin film for a light emitting layer of an organic EL element was formed.
[0059]
Also, as a condition of the apparatus of the present invention, a substrate film formation surface and an upper end surface of the opening are brought into close contact with each other, the opening has a size of one side of 100 μm, and an opening for a 64 × 128 full color matrix is prepared. The heating temperature of the vaporization vessel was set to 400 ° C.
[0060]
As a substrate, a substrate with a relatively large area of size, length: 200 mm × width: 200 mm was prepared.
[0061]
An ITO electrode layer, etc. is formed on the substrate in a predetermined pattern, and the surface is UV / O_Three After cleaning, it is fixed to the substrate holder of the vacuum evaporation system and the inside of the tank is 1 × 10^-FourThe pressure was reduced to Pa or lower. 4,4 ′, 4 ″ -tris (—N- (3-methylphenyl) -N-phenylamino) triphenylamine (hereinafter, m-MTDATA) was deposited to a thickness of 80 nm at a deposition rate of 0.1 nm / sec. Next, N, N′-diphenyl-N, N′-m-tolyl-4,4′-diamino-1,1′-biphenyl (hereinafter referred to as TPD) was deposited at a deposition rate of 0.1 nm. The film was deposited to a thickness of 20 nm at / sec to form a hole transport layer.
[0062]
Subsequently, the light emitting layer was formed using the apparatus of the present invention. At this time, the raw material supply source, the supply amount adjusting means, and the raw material vaporization means were prepared in correspondence with the red, green, and blue light emitting layers, respectively. Tetrahydrofuran (THF: boiling point = 80 ° C.) was used as the solvent. As a raw material for the red light emitting layer, tris (8-quinolinolato) aluminum (Alq3: vaporization temperature = 300 ° C.) doped with 1% by volume of dicyanomethylpyran (hereinafter DCM: vaporization temperature = 290 ° C.) to a thickness of 50 nm It vapor-deposited and it was set as the electron injection transport and the light emitting layer (red light emitting layer). As a green light emitting layer material, Alq3 doped with 1% by volume of coumarin 6 (vaporization temperature = 150 ° C.) was deposited to a thickness of 50 nm to form an electron injection transport / light emitting layer (green light emitting layer). As a blue light emitting layer material, diphenylanthracene dimer (hereinafter DPA: vaporization temperature = 330 ° C.) was deposited to a thickness of 50 nm to form a light emitting layer (blue light emitting layer).
[0063]
In the apparatus of this embodiment, the substrate is fixed to an XY table for alignment adjustment, and this is moved under microcomputer control to perform alignment for each of RGB.
[0064]
Further, after being transferred to a vapor deposition apparatus, tris (8-quinolinolato) aluminum (Alq3) was vapor-deposited to a thickness of 10 nm at a vapor deposition rate of 0.1 nm / sec to form an electron injecting and transporting layer.
[0065]
Next, while maintaining the reduced pressure, AlLi (Li: 7 at%) was evaporated to a thickness of 5 nm, and Al was evaporated to a thickness of 200 nm to form an electron injection electrode.
[0066]
The resulting organic EL display is 10 mA / cm² As a result, it was confirmed that all the RGB pixels emitted light normally and operated. Further, it has been found that the invention device can perform painting separately with a pixel area of about 100 μm on one side as a minimum unit.
[0067]
【The invention's effect】
As described above, according to the present invention, by using an evaporation source capable of supplying a continuous material, it is possible to perform stable deposition for a long period of time, and an organic thin film can be easily applied separately, and a mixture or doping can be obtained. It is possible to realize an organic thin film manufacturing apparatus and manufacturing method that can be applied to organic materials that have been prepared and that can also be applied to vapor deposition at a relatively low temperature.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a basic configuration example of a manufacturing apparatus according to the present invention.
FIG. 2 is a partial cross-sectional schematic configuration diagram showing a specific configuration example of a mass flow controller.
FIG. 3 is a cross-sectional view showing a more detailed configuration example of the evaporation container.
[Explanation of symbols]
1 Raw material solution
2 Raw material storage tank
3 Mass flow controller
4 Vaporization container
5 Substrate
6 Temperature detection means
7 Heating control device

Claims (6)

A raw material supply source for supplying a raw material solution in which the organic material of the organic EL element constituent film is dissolved in a solvent;
A supply amount adjusting means for adjusting and supplying the raw material solution from the raw material supply source to a certain amount;
A raw material vaporization means for vaporizing the supplied raw material solution,
The raw material vaporization means includes a vaporization container formed in a container shape having a predetermined capacity, a heating means for heating the raw material solution supplied in the vaporization container to a temperature higher than the vaporization temperature of the organic material, and the vaporization container It is formed, and an opening for supplying the gas phased material to the deposition surface, the raw material solution supplied is heated to a temperature higher than the vaporization temperature of the organic material vaporized in the container by the heating means An apparatus for manufacturing an organic EL element that vaporizes and discharges a raw material vaporized by an increase in the internal pressure of the vaporization container due to the vaporization and deposits it on the film formation surface to form an organic EL element constituent film . The organic EL device manufacturing apparatus according to claim 1, wherein a substrate having a film formation surface is disposed on the vaporization container, and the opening is formed at a position corresponding to the film formation surface of the substrate. The apparatus for manufacturing an organic EL element according to claim 2 , further comprising an alignment adjustment mechanism for the substrate. The said supply amount adjustment means is a manufacturing apparatus of the organic EL element in any one of Claims 1-3 which controls the flow volume of a raw material solution by a mass flow control system. An adjustment step of adjusting the raw material solution in which the organic material of the organic EL element constituent film is dissolved in a solvent to a certain amount;
A supply step of supplying the adjusted raw material solution to the vaporization container formed in a container shape having a predetermined capacity;
A vaporization step of vaporizing the supplied raw material solution,
In the vaporization step, the vaporization container is heated to a temperature higher than the vaporization temperature of the organic material, the supplied raw material solution is vaporized, and the vaporized raw material is formed in the vaporization container due to an increase in the internal pressure of the vaporization container due to vaporization. A method for manufacturing an organic EL element, wherein the organic EL element is formed by discharging from an opening for supplying to the film formation surface and depositing on the film formation surface. The manufacturing method of the organic EL element of Claim 5 which performs the said adjustment process, a supply process, and a vaporization process for every kind of said organic EL element structure film.

Images