JPH10158820A - Vapor deposition device, organic vaporization source and production of organic thin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the temp. overshooting of an org. thin film material, to shorten the heating and cooling time and to suppress the generation of org. compd. vapor except during vapor deposition. SOLUTION: An org. thin film material arranged in an org. vaporization source is placed in an inert gas atmosphere and heated to a specified temp. (S3 , S4 ), evacuation is conducted to generate the vapor of the material (S5 ), and an org. thin film is formed (S6 , S7 ). Since the vaporization of the material is suppressed in the inert gas atmosphere, the material is effectively utilized. Further, as the inert gas acts as a heating medium, the heating rate is increased, and the heat is sufficiently equalized. The cooling rate is increased, when the cooling is performed in the inert gas atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an organic thin film manufacturing method for forming an organic thin film on the surface of a film-forming target, and a vapor deposition apparatus and an organic evaporation source suitable for performing the method.

[0002]

2. Description of the Related Art Conventional electronic technology has been directed to inorganic substances mainly in semiconductors, but in recent years, attention has been paid to functional organic thin films using organic compounds.

[0003] As a reason for using an organic compound, a wider variety of reaction systems and characteristics can be used than an inorganic compound. Surface treatment can be performed with lower energy than inorganic substances. The advantage is that.

There are organic EL elements, piezoelectric sensors, pyroelectric sensors, electric insulating films, and the like that use a functional organic thin film. Of these, the organic EL elements are attracting attention because they can be used as display panels. Therefore, a technique capable of uniformly forming an organic thin film on a large-area substrate has been demanded in order to increase the diameter of a display portion.

However, a vacuum evaporation apparatus for forming a metal thin film such as an Al thin film or a SiO ₂ thin film or an inorganic thin film is diverted in the conventional organic thin film manufacturing process. Not yet developed.

Here, when the organic thin film material is compared with the inorganic thin film material, the following characteristics are recognized in the organic thin film material.

[0007] The organic thin film material has a high vapor pressure, and the evaporation source temperature is 0 ° C (lower in some cases) to 40 ° C, while the metal evaporation source is as high as about 600 ° C to 2000 ° C.
It is between 0 ° C., and often causes decomposition in a temperature range of 20 ° C. to 400 ° C. Therefore, it is desirable to perform precise temperature control during evaporation. When forming a metal thin film, an E / B vapor deposition apparatus that irradiates an electron beam to a metal evaporation source is generally used. However, the energy is too high for an organic thin film material, and the electron beam is decomposed when irradiated with the electron beam. Resulting in.

[0008] Among organic thin film materials, there are powder materials, but in general, powder materials have poor heat conduction. In particular, when trying to heat in a vacuum, the temperature is increased or cooled by the heat insulating effect of the vacuum. Unfortunately, there may be a delay between the control temperature and the actual temperature. On the other hand, once the temperature of the evaporation source once rises, it is difficult for such a powdery material to be cooled only by radiative cooling, and evaporation may not end immediately even if heating is stopped. It is a so-called problem that the "cut" of evaporation is bad.

The organic thin film material has a high vapor pressure,
What is adsorbed on the tank wall of the low-temperature vacuum chamber may be released (re-evaporated) due to the rise in the temperature of the vacuum chamber, and if the released particles are mixed into the organic thin film, the characteristics of the organic thin film may be degraded .

There are many organic thin film materials that easily adsorb moisture, but there are some materials whose properties are deteriorated when moisture is adsorbed. In addition, when moisture is taken into the organic thin film when forming a multilayer organic thin film, the characteristics of the interface may change. In particular, when producing a functional element such as an organic EL element or a pyroelectric element, a defect may occur in the final performance.

A metal evaporation source has a directional property when evaporating, and the direction has a property of proceeding substantially straight from the evaporation source according to the cosine law (COS LAW). May cause.

When forming a vapor-deposited polymer film, it is necessary that the composition ratio of two organic thin-film materials to be vapor-deposited at the same time follows the stoichiometric ratio. If the composition ratio deviates from the stoichiometric ratio, the function of the piezoelectric device is lost or deteriorated. In order to make the composition ratio stoichiometric, precise control of the film formation rate is required.

As described above, there are many difficulties in handling organic thin film materials. There are the following types of evaporation sources of a conventionally used vacuum evaporation apparatus (FIG. 8A).
(e)) Neither is suitable for use due to the properties of the organic thin film material described above and the required properties of the organic thin film.

(A) The evaporation source container 101 is formed of metal,
Heating by direct energization to evaporate the thin film material (Fig. 8
(a): Direct resistance heating type) This method is excellent in temperature stability in a temperature range in which a metal melts, but is poor in stability and controllability in a temperature range in which an organic thin film material evaporates. Therefore, the generation rate of the organic compound vapor (vapor of the organic thin film material) becomes unstable. Some of the organic thin film materials corrode or react with the metal. However, an organic thin film material having such a corrosive and reactive property with respect to the metal constituting the container cannot be used.

(B) A method in which the resistance heating elements 112 and 122 are placed around the evaporation source containers 111 and 121 and indirectly heated by applying electric current to evaporate the thin film material.
(b): Conical basket type, (c): K cell type). This method has excellent temperature stability in a temperature range in which the metal melts, but has poor stability and controllability in a temperature range in which the organic thin film material evaporates. Therefore, the generation speed of the organic compound vapor becomes unstable. Also, the resistance heating element 112 of this type
It is common to use a bare metal wire, but an organic thin film material is more likely to cause a wraparound phenomenon than an inorganic thin film material. When a metal chelate or the like is contained in the organic thin film material, a short circuit may occur between the resistance heating elements 112.
In addition, since the K-cell type evaporation source has a complicated structure,
Internal cleaning is difficult and the thin film material cannot be completely removed. Therefore, when the thin film material in the evaporation source containers 111 and 121 is replaced with a different type, there is a possibility that contamination of the previous thin film material occurs.

(C) A method in which a thin film material is radiatively heated and evaporated by an infrared lamp 133 using an evaporation source container 131 made of a light transmissive material such as quartz (FIG. 3D: lamp heater type evaporation source). This method has excellent temperature controllability at low temperatures, but the specific heat capacity of the evaporation source container 131 is large, so that a temperature difference occurs between the control temperature and the actual temperature of the thin film material. On the other hand, when controlling by measuring the temperature of the thin film material itself, temperature overshoot is likely to occur, and the organic thin film material may be decomposed. Further, in order to transmit the heat rays emitted from the infrared lamp 133, the evaporation source container 131 needs to be made of a transparent material such as quartz, but the transparent material is easily damaged during cleaning or replacement. Further, the evaporation source container 1
If the material 31 becomes fogged by long-term use and the transmission intensity of infrared rays varies depending on the position, the organic thin film material having poor thermal conductivity may cause local overheating. In addition, some organic thin-film materials are deteriorated by light of a specific wavelength, but such organic thin-film materials cannot generate vapor by this method.

(D) A method of irradiating the thin film material with the electron beam 145 and evaporating it (FIG. 3E: E / B gun). Irradiation with the electron beam 145 decomposes the organic thin film material and cannot be used.

As described above, the prior art methods (A) to (D) for evaporating an inorganic thin film material are incomplete for application to an organic thin film material. In particular, the problem of decomposition of the organic thin film material due to the temperature overshoot and the difficulty of heating the organic thin film material are problems that have not been observed with inorganic thin film materials, and their solutions have been desired.

[0019]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned disadvantages of the prior art, and has as its object to prevent the occurrence of temperature overshoot at the time of temperature rise and the main component of the organic thin film material. It is an object of the present invention to provide a technique capable of changing a temperature to a desired temperature in a short time without thermally decomposing the compound.

It is another object of the present invention to provide a technique capable of suppressing the generation of organic compound vapor other than during vapor deposition and effectively utilizing an organic thin film material.

[0021]

According to a first aspect of the present invention, there is provided an apparatus having a vacuum chamber configured to be evacuable and an organic evaporation source containing an organic thin film material. A vapor deposition apparatus configured to form an organic thin film on the surface of a film-forming target disposed in the vacuum chamber by controlling the temperature of the organic thin film material to generate a vapor thereof; The tank is provided with a gas inlet so that an inert gas can be introduced into the vacuum tank.

According to a second aspect of the present invention, there is provided an evaporation source container in which an organic thin film material is disposed, wherein the vapor is generated by controlling the temperature of the organic thin film material, and discharged from a discharge port into a vacuum chamber. An organic evaporation source configured so that a gas valve is provided between the evaporation source container and the discharge port, and when the gas valve is closed, the inside of the evaporation source container becomes a vacuum atmosphere or an inert gas atmosphere. It is also characterized by being configured to be able to be placed.

On the other hand, the method according to the present invention is an organic thin film forming method for depositing an organic thin film material disposed in an organic evaporation source, wherein the start and the end of the organic thin film deposition are based on the introduction of an inert gas. It is characterized in that it is performed by changing the degree of vacuum.

According to a fourth aspect of the present invention, in the method of the present invention, the temperature of the organic thin-film material disposed in the organic evaporation source is changed to a predetermined temperature to generate vapor of the organic thin-film material, and the vapor of the organic thin-film material is vacuum A method for producing an organic thin film, wherein the organic thin film material is discharged in a tank and an organic thin film is formed on a film formation target disposed in the vacuum tank, wherein the temperature change of the organic thin film material is performed in an inert gas atmosphere. Features.

In the method for producing an organic thin film according to the fourth aspect, as in the method according to the fifth aspect, the inert gas atmosphere is preferably set to a pressure of 13.3 Pa or more.

Further, any one of claims 4 and 5
As for the method for producing an organic thin film described in the above item, the organic thin film material is placed in a vacuum atmosphere after the temperature of the organic thin film material is changed to a predetermined temperature, and the organic thin film is Formation can begin.

In the method of manufacturing an organic thin film according to any one of claims 4 to 6, as in the method of the invention described in claim 7, before the organic thin film material is placed in an inert gas atmosphere, a vacuum is applied. It can be placed in an atmosphere and degassed.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an organic thin film, comprising the steps of:
When lowering the temperature of the organic thin film material, the organic thin film material can be placed in an inert gas atmosphere.

The method for producing an organic thin film according to any one of claims 4 to 8 described above is described in claim 9.
It is effective to use a powder for the organic thin film material as in the method of the invention described.

According to the configuration of the vapor deposition apparatus of the present invention described above,
After evacuating the vacuum chamber, an inert gas can be introduced and the organic thin film material in the organic evaporation source can be placed in an inert gas atmosphere, so when controlling the temperature of the organic thin film material, the inert gas is removed. Convection is generated, and the rate of temperature rise and temperature can be increased.

In particular, when the organic thin film material is a powder, an inert gas penetrates between the particles of the powder and acts as a heat medium, so that local overheating and temperature overshoot of the organic thin film material do not occur. Decomposition of the organic thin film material can be prevented.

Generally, the amount of organic compound vapor generated is smaller in an inert gas atmosphere than in a vacuum atmosphere.
When the heating and cooling of the organic thin film material is performed in an inert gas atmosphere, the generation of organic compound vapor is suppressed during that time, so that useless vapor that is not used for forming the thin film is not generated. Efficiency can be increased and manufacturing costs can be reduced.

In particular, if the temperature is raised in an inert gas atmosphere, the temperature uniformity is improved. Therefore, when the inert gas atmosphere is changed to a vacuum atmosphere to generate the organic compound vapor, the organic compound vapor The time required for the generation rate to stabilize becomes shorter, and the vapor deposition operation can be started earlier.

On the other hand, when the organic thin film material is placed in an inert gas atmosphere at the time of cooling, not only the cooling rate is increased, but also the
Evaporation of organic compounds is stopped, so the evaporation is “clean”
And the waste of expensive organic evaporation materials is eliminated.

Next, according to the structure of the organic vapor deposition source of the present invention described above, the organic thin film material is placed in the vaporization source container, heated up to a predetermined temperature to generate the vapor, and discharged from the discharge port into the vacuum chamber. Before releasing the organic thin film material into an inert gas atmosphere, the inside of the evaporation source container is once evacuated with the gas valve provided between the evaporation source container and the discharge port closed, and then an inert gas is introduced. Can be put on.

When the organic thin film material is heated to a temperature at which an organic compound vapor is generated in a vacuum atmosphere in the state of the inert atmosphere, wasteful organic compounds are introduced without introducing an inert gas into a vacuum chamber having a large volume. No need to generate steam. Compared to the case where inert gas is introduced into the vacuum chamber,
The amount of inert gas used can be reduced, and the time required for the pressure of the inert gas atmosphere to stabilize and the time required to evacuate the vacuum chamber are shortened, thereby shortening the working time.

The start and end of the vapor deposition are performed by changing the degree of vacuum based on the introduction of the inert gas (when the vapor deposition is started, the introduction of the inert gas is stopped and the degree of vacuum is increased.
At the end of vapor deposition, an inert gas is introduced to a pressure that does not evaporate), thereby turning on vapor deposition only by changing the degree of vacuum.
(Start) and OFF (stop). This eliminates waste of expensive organic evaporation materials.

According to experiments, the pressure of such an inert gas atmosphere is 2.0 × 10 ³ Pa (15 To
rr), an effect of 13.3 Pa (0.1 Torr) has been confirmed on the low pressure side, but if the pressure is too high, the amount of inert gas used increases, and the time required for evacuation increases. Therefore, a pressure of 66.5 Pa (0.5 Torr) or less is desirable.

When the organic thin film material is heated to a predetermined temperature in an inert atmosphere, and then the vacuum atmosphere is started to form an organic thin film on a film-forming target, the pressure of the vacuum atmosphere is 1.33 × 10 ⁻⁴ Pa (1.0 × 10 ⁻⁶ Torr)
The following pressure, desirably 1.33 × 10 ⁻⁵ Pa (1.0
When the pressure is equal to or less than × 10 ⁻⁷ Torr, the quality of the organic thin film is improved.

In order to degas the organic thin film material, it is necessary to place the organic thin film material in a vacuum atmosphere and heat it at a temperature lower than the evaporation temperature before the organic thin film material is heated in an inert gas atmosphere. Is desirable.

[0041]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference numeral 10 in FIG. 1 denotes a vapor deposition apparatus according to an example of the present invention, which has a vacuum chamber 11 which can be evacuated by a vacuum pump (preferably a cryopump) not shown. .

A plurality of organic evaporation sources are provided on the bottom wall of the vacuum chamber 11, and here, two organic evaporation sources 12 ₁ , 1
It denotes the 2 _2. The organic evaporation sources 12 ₁ , 12
₂ has discharge ports 14 ₁ and 14 ₂ , respectively. When the organic thin film material is placed in each of the organic evaporation sources 12 ₁ and 12 ₂ and heated to a predetermined temperature, the organic thin films are discharged from the discharge ports 14 ₁ and 14 ₂ . The organic compound vapor constituting the thin film material can be released into the vacuum chamber 11.

A substrate holder 30 is provided above the organic evaporation sources 12 ₁ and 12 ₂ , and a surface on which a film is to be formed is directed to the discharge ports 14 ₁ and 14 ₂ . 1
3 (glass substrate) is held.

[0044] The vacuum chamber 11, gas pipes 28 are connected, the inert gas filled in the gas cylinder 22 (a nitrogen gas in this case), the valve 24 _1, the mass flow controller 23, via the valve 24 ₂ The gas flows through the gas pipe 28 while controlling the flow rate, and the inert gas can be introduced into the vacuum chamber 11 from the gas inlet 29.

An openable and closable substrate shutter 35 is provided in the vicinity of the surface of the film forming object 13, while the organic evaporation source 12 is
_1, the 12 _second outlet 14 _1, 14 ₂ near openable evaporation source shutters 33 _1, 33 ₂ are provided, even if the organic compound vapor is discharged from the discharge port 14 _1, 14 ₂ , The substrate shutter 35 and the evaporation source shutters 33 ₁ , 3
If Close 3 _2, organic compound vapor is prevented reach the film-forming target 13 surface.

The position above the evaporation source shutters 33 ₁ , 33 ₂ is determined so that the organic compound vapor discharged from the discharge ports 14 ₁ , 14 ₂ does not reach the film formation target 13.
The film thickness monitors 36 ₁ and 36 ₂ are arranged, and when the evaporation source shutters 33 ₁ and 33 ₂ are opened, the film thickness monitors 36 ₁ and 36 ₂
36 ₂ organic compound vapor adheres respectively, and is configured so as to measure an organic thin film formation rate on the film formation object 13.

The LN ₂ shrouds 31 and 32, which are liquid nitrogen containers, are provided around the film formation target 13 and the bottom wall of the vacuum chamber 11.
When liquid nitrogen is introduced after the inside of the vacuum chamber 11 is evacuated, water molecules existing in the vacuum chamber 11 are efficiently adsorbed to the respective LN ₂ shrouds 31 and 32. It is configured as follows.

During the vapor deposition, the LN ₂ shrouds 31 and 32 trap the organic compound vapor directed toward the wall surface of the vacuum chamber 11, and the organic compound vapor adsorbed on the wall surface is released again to form the film forming object 13. It is configured not to be mixed into the organic thin film formed on the surface.

On the other hand, a pipe 37 is provided in the substrate holder 30.
When the heat medium is circulated in the pipe 37, the film formation target 13 during the formation of the organic thin film is heated to 50 ° C.
It is configured to be capable of heating with good controllability in a temperature range of 100 ° C. By controlling the temperature of the film formation target 13,
It is configured so that an organic thin film having good adhesion can be formed on the surface.

The organic evaporation sources 12 _1, 12 ₂ is configured to attach hermetically to the vacuum chamber 11 the bottom wall by a flange 59 and O-ring 58 as shown in FIG. 2, a casing 51 upper portion of the discharge port 14 ₁ is configured to 14 ₂ is directed into the vacuum chamber 11.

An evaporating source container 50 is arranged in the casing 51, and a bottomed cylindrical soaking plate 55 is arranged around the evaporating source container 50. , A micro heater 52 is wound.

A thermocouple 56 is provided at the bottom of the soaking plate 55, and is disposed outside the vacuum chamber 11 while monitoring the temperature of the soaking plate 55 to a predetermined temperature by the thermocouple 56. When the micro heater 52 is energized from a power source to generate heat, the organic thin film material 54 contained in the evaporation source container 50 can be maintained at a desired temperature in a temperature range of 150 ° C. to 400 ° C.

A reflector 53 is arranged around the micro-heater 52, and reflects heat radiation from the micro-heater 52 toward the casing 51 so as to reflect the heat radiation.
1, so that the evaporation source container 52 is efficiently heated.

The winding density of the micro-heater 52 is dense on the discharge ports 14 ₁ and 14 ₂ and is sparse on the bottom side of the evaporation source container 52, and the temperature of the discharge ports 14 ₁ and 14 ₂ is reduced. source is configured to be higher than the temperature of the vessel 52 and organic matter 54, as a result, generated organic compound vapor in the vicinity of discharge port 14 _1, 14 ₂ are prevented from adhering.

[0055] the following chemical formula such organic evaporation sources 12 _1, 12 _2, one of the organic evaporation sources 12 _1,

[0056]

Embedded image

Al which is a sublimable organic thin film material represented by
_{q 3 [Tris (8-hydroxyquinoline} ) aluminium, sublime
d] was arranged as an organic thin film material.

First, the above-described vacuum pump was started, the inside of the vacuum chamber 11 was set in a vacuum atmosphere, and the object 13 for film formation was carried in that state. The vacuum chamber 11 further evacuated, the film forming object 13, the Alq ₃ in the organic evaporation sources 12 ₁ 1.0 × 10 ^-6
It was placed in a vacuum atmosphere of Torr (FIG. 4: S ₁ ).

[0059] energized in this state to the micro heater 52 of the organic evaporation sources 12 _1, the Alq ₃ 100 ℃ ~200 ℃
Heated. At this temperature, the amount of steam generated from Alq ₃ is small, and the adsorbed gas is released. For 20 minutes to 30 minutes degassing (S _2), then introducing nitrogen gas as an inert gas from the gas inlet 29 while evacuating the vacuum chamber 11 (S _3).

[0060] When the vacuum chamber and an organic evaporation source 12 ₁ 11 was stabilized at an inert gas atmosphere at a pressure 0.1 Torr, increasing the amount of current supplied to the micro heater 52, the evaporation temperature Alq ₃ of the evaporation source 12 ₁ (In this Alq ₃ 300 ℃
(S ₄ ). At the time of this temperature rise, Alq
Since ₃ is placed in an inert gas atmosphere, the heat is efficiently transferred between Alq ₃ particles, temperature overshoot does not occur, also, the occurrence of Alq ₃ vapor was observed.

When Alq ₃ is stabilized at the evaporation temperature, the introduction of the inert gas is stopped, and the inside of the vacuum chamber 11 is again set to 1.0 ×
A vacuum of 10 ^-6 Torr was established. When the vacuum chamber 11 is stabilized at the pressure, while still closed substrate shutter 35 is opened evaporation source shutters 33 _1, from outlet 14 ₁ to release the Alq ₃ vapor.

[0062] Alq ₃ vapor reaches the film thickness monitor 36 _1, the organic thin film is formed on the surface thereof, and measuring the growth rate, opening the substrate shutter 35 where the growth rate is stabilized, the film-forming target 13 Organic thin film (Al
q ₃ to initiate the formation of a thin film) (S _6).

[0063] performs the formation of the organic thin film 5 min, closed and substrate shutter 35 and the evaporation source shutter 36 ₁ upon reaching a predetermined thickness, and stops energizing the micro heater 52, and ends the evaporation (S ₇₎ .

[0064] Then, an inert gas is introduced from the gas inlet 29 into the vacuum chamber 11, place the Alq ₃ in the organic evaporation source 12 ₁ to an inert gas atmosphere at a pressure 0.1 Torr, Alq
₃ Stop generating steam. At this time, since the inert gas becomes a heat medium and convection occurs, cooling of Alq ₃ is accelerated.

FIG. 5 shows changes in the temperature and the evaporation rate of Alq ₃ from the start of the temperature rise of Alq ₃ in an inert gas atmosphere to the completion of the evaporation and cooling in the above-mentioned organic thin film forming step. Show. In addition, Alq ₃ under a vacuum atmosphere is represented by the following chemical formula,

[0066]

Embedded image

FIG. 6 is a graph showing the relationship between the temperature of the TPD and the evaporation rate. From the graph of FIG. 6, it can be seen that in a vacuum atmosphere, organic compound vapor is generated at a temperature of about 300 ° C. for Alq _{3 and} at a temperature of about 230 ° C. for TPD. On the other hand, it can be seen from the graph of FIG. 5 that even when Alq ₃ is heated to a temperature at which organic compound vapor is generated in a vacuum atmosphere, no Alq ₃ vapor is generated in an inert gas atmosphere. Therefore, the generation of organic compound vapor
It can be seen that the pressure can be controlled by the pressure of the inert gas atmosphere. As can be seen from the graph of FIG. 5, when the temperature of the organic thin film material is raised in an inert gas atmosphere, no temperature overshoot is observed.

FIG. 7 is a graph showing changes in the temperature and evaporation rate of Alq ₃ when an organic thin film is formed without using an inert gas, as in the prior art, in comparison with the above-described organic thin film forming method. Show. When the temperature is raised, Alq ₃ is insulated in vacuum, so that partial overheating occurs and a temperature overshoot is observed. In addition, it can be seen that Alq ₃ vapor is generated at the time of temperature rise and cooling, and a large amount of Alq ₃ vapor that does not contribute to the formation of the organic thin film is generated.

Next, an organic evaporation source suitable for heating and cooling a liquid organic thin film material will be described. Referring to FIG.
Is an oil bath organic evaporation source that controls the temperature (heating / cooling) of the organic thin film material with a liquid heat medium, and in particular, keeps the temperature of the organic thin film material constant in the temperature range of -20 ° C to 180 ° C. Suitable for maintaining and generating organic compound vapors.

The organic evaporation source 42 includes a casing 71
, An evaporation source container 70, and a heating / cooling source 60. The evaporation source container 70 is fitted in a casing 71 to form a double container structure 78. Heating / cooling source 60
Are an oil bath 63, a heater 65, and a cooler 64
, So that the silicone oil 61 stored in the oil bath 63 can be heated and cooled.

The supply pipe 6 is provided in the silicone oil 61.
6 ₁ and the tip is immersed, operating the circulation pump 62 provided in the middle of the supply pipe 66 _1, an oil bath 6
Silicone oil 61 in 3 sucked through the supply pipe 66 ₁ is supplied to the double container structure 78, after heat exchange with the organic thin film material 74 via the evaporation source container 70,
And it is configured to return to the oil bath 63 through the discharge pipe 66 _1.

At the upper end of the evaporation source container 70, a vapor discharge pipe 7
One end of 5 is airtightly connected, and is configured such that the organic compound vapor generated in the evaporation source container 70 can be discharged from a discharge port 44 at the other end into a vacuum chamber (not shown).

In the middle of the steam discharge pipe 75, the gas valve 4
5 is provided, and the gas valve 4 of the steam discharge pipe 75 is provided.
One end of a gas pipe 43 is connected to a position between the gas source 5 and the evaporation source container 70. The other end of the gas pipe 43, a gas cylinder 46 that inert gas such as nitrogen gas or argon gas is filled is provided with, in the middle of the gas pipe 43, gas valve 48 _1, 48 ₂ are provided. Gas pipe 43 is branched between the gas valves 48 _1, 48 _2, gas valve 48 ₃ is provided in the middle of the branch portion,
The tip is connected to a vacuum pump 47.

In a state where the organic thin film material 74 is contained in the evaporation source container 70, the gas valve 4
5,48 ₂ closed, opened gas valve 48 _1, 48 _3, the evaporation source vessel 70 and operates the vacuum pump 47 is evacuated, the organic thin film material 74 is placed in a vacuum atmosphere.

In this state, the circulation pump 62 is operated, and the temperature of the organic thin film material 74 is raised to a temperature at which no organic compound vapor is generated in a vacuum atmosphere, and degassing is performed.

[0076] Then, close the gas valve 48 _3, opened the gas valve 48 _2, inert gas in the gas cylinder 46 is introduced into the evaporation source vessel 70 through the gas pipe 43, the organic thin film material 74 in an inert gas atmosphere Is placed.

The inside of the evaporation source container 70 is 0.1 to 15.0 To
to a pressure of about rr, close the gas valve 48 _1, 48 ₂ in a state of placing the organic thin film material 74 in an inert gas atmosphere, then, raising the temperature of the silicone oil 61, the organic thin film material 74, the organic under vacuum The temperature is raised to the evaporation temperature at which the compound vapor is generated. At this time, the organic thin film material 74
Since is placed in an inert gas atmosphere, no organic compound vapor is generated.

[0078] The organic thin film material 74, where stable at the evaporation temperature, close the gas valve 48 _2, gas valve 48 _1,
Open the 48 _3, the evacuated organic compound vapor begins to occur within the evaporation vessel 70 by the vacuum pump 47.

When the inside of the evaporation source container 70 is stabilized at a desired pressure, when the gas valve 45 is opened, the organic compound vapor passes through the vapor discharge pipe 75 and is discharged from the discharge port 44 into the vacuum chamber.

A micro heater 72 is provided in the vapor discharge pipe 75.
Is wound so that the temperature can be controlled separately from the silicone oil 61. When discharging the organic compound vapor, the micro heater 72 is energized to heat the vapor discharge tube 75 so that the temperature of the vapor discharge tube 75 becomes higher than the temperature of the organic thin film material 74, and the organic compound vapor generated in the evaporation source container 70 is discharged as vapor. The gas may be adsorbed in the middle of the pipe 75 or the gas valve 4
5 is not blocked.

After the inside of the vacuum chamber was set to a pressure of 1.0 × 10 ⁻⁶ Torr, the evaporation source shutter provided above the discharge port 44 was opened, and the organic compound was monitored by a film thickness monitor disposed above the discharge port 44. After confirming that the generation of steam has stabilized,
Opening the substrate shutter and starting the formation of the organic thin film on the surface of the film formation target is the same as in the vapor deposition apparatus of FIG.

After the vapor deposition, the gas valve 45 is closed, an inert gas is introduced into the evaporation source container 70, the cooler 64 is operated to lower the temperature of the silicone oil 63, and the inert gas 70 generates organic compound vapor. The organic thin film material 74 is cooled in a state where the temperature is suppressed. On the other hand, after the evaporation is completed, the object on which the organic thin film is formed is carried out, the unprocessed object is carried in, and the next evaporation operation is started.

The case where only one organic thin film is formed has been described above. However, when a plurality of organic evaporation sources are used to form a multilayer organic thin film, the temperature rise and cooling of the organic thin film material in each organic evaporation source may be performed. In this case, it may be placed in an inert gas atmosphere.

The organic thin film material may be a liquid or a solid. In particular, in the case of a powdery material, an inert gas enters between the powder particles and becomes a heat medium. The cooling rate is increased, and the heat uniformity of the organic thin film material can be improved.

Although nitrogen gas is used as the above-mentioned inert gas, another gas can be used as long as it does not react with the organic thin film material.

[0086]

According to the present invention, no wasteful organic compound vapor is generated during heating and cooling. The temperature rising rate and the cooling rate of the organic thin film material are increased. Temperature controllability is improved, and temperature overshoot does not occur. The thermal uniformity of the organic thin film material is improved,
The time required for the generation rate of the organic compound vapor to stabilize becomes shorter.

[Brief description of the drawings]

FIG. 1 shows an example of a vapor deposition apparatus of the present invention.

FIG. 2 shows an example of an organic evaporation source used in the vapor deposition apparatus.

FIG. 3 shows an example of the organic evaporation source of the present invention.

FIG. 4 is a flowchart for explaining the steps of the method of the present invention.

FIG. 5 is a graph for explaining temperature change and evaporation rate change of an organic thin film material when an organic thin film is formed by the method of the present invention.

FIG. 6 is a graph for explaining the relationship between the temperature of Alq ₃ and TPD and the evaporation rate.

FIG. 7 is a graph for explaining a change in temperature and a change in evaporation rate of an organic thin film material when an organic thin film is formed by a conventional technique.

8 (a) to 8 (e) are diagrams for explaining a conventional evaporation source.

[Explanation of symbols]

10: Vapor deposition device 11: Vacuum chamber 12 ₁ , 12 ₂ ,
42 organic evaporation source 13 film formation target 29 gas inlet 50
70: evaporation source container 54, 74 ... organic thin film material

Claims (9)

[Claims] A vacuum chamber configured to be capable of evacuating, and an organic evaporation source containing an organic thin film material, wherein the vacuum chamber is controlled by controlling a temperature of the organic thin film material to generate a vapor thereof. A vapor deposition apparatus configured to be able to form an organic thin film on the surface of a film formation target disposed therein, wherein a gas inlet is provided in the vacuum chamber, and an inert gas can be introduced into the vacuum chamber. A vapor deposition apparatus characterized by being configured as described above. 2. An organic source having an evaporation source container in which an organic thin film material is disposed, wherein the organic thin film material is controlled so as to generate a vapor by controlling the temperature of the organic thin film material and discharge the vapor into a vacuum chamber from a discharge port. An evaporation source, wherein a gas valve is provided between the evaporation source container and the discharge port, and when the gas valve is closed, the inside of the evaporation source container can be placed in a vacuum atmosphere or an inert gas atmosphere. An organic evaporation source, characterized in that: 3. An organic thin film forming method for depositing an organic thin film material disposed in an organic evaporation source, wherein the start and the end of the deposition of the organic thin film are performed by changing the degree of vacuum based on the introduction of an inert gas. Organic thin film forming method. 4. An organic thin-film material disposed in an organic evaporation source is changed in temperature to a predetermined temperature to generate vapor of the organic thin-film material, and the vapor of the organic thin-film material is discharged into a vacuum chamber. A method for manufacturing an organic thin film, wherein an organic thin film is formed on an object to be formed disposed therein, wherein the temperature of the organic thin film material is changed in an inert gas atmosphere. 5. The inert gas atmosphere is 13.3 Pa.
5. The method for producing an organic thin film according to claim 4, wherein the pressure is the above pressure. 6. The method according to claim 4, wherein after the temperature of the organic thin film material is changed to a predetermined temperature, the organic thin film material is placed in a vacuum atmosphere to start forming an organic thin film on the film formation target. The method for producing an organic thin film according to claim 1. 7. The method of manufacturing an organic thin film according to claim 4, wherein the organic thin film material is placed in a vacuum atmosphere and degassed before being placed in an inert gas atmosphere. Method. 8. The method according to claim 4, wherein, after forming the organic thin film on the film-forming target, when the organic thin-film material is cooled, the organic thin-film material is placed in an inert gas atmosphere.
The method for producing an organic thin film according to claim 1. 9. The method for producing an organic thin film according to claim 3, wherein the organic thin film material is a powder.