JP2012207238A - Vapor deposition method and vapor deposition apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the cooling time of an evaporation source by applying a vapor deposition method to a film deposition process of forming a vapor deposition film on a substrate.SOLUTION: In the vapor deposition process, vapor deposition material gas is generated from an evaporation source including a crucible for storing the vapor deposition material, a heating unit for heating the crucible, a nozzle for emitting the vapor deposition material vaporized in the crucible toward an object to be processed, and a reflector 15 arranged around the crucible, and a vapor deposition film is formed on the object to be processed. Further, in the cooling process, the crucible is cooled by making refrigerant flow through a cooling body 16 fixed to the reflector 15. The cooling process includes: a refrigerant gas supply process for making the refrigerant gas flow through the cooling body 16; and a refrigerant liquid supply process of making the refrigerant liquid, having the heat capacity higher than that of the refrigerant gas, flow through the cooling body 16 after the refrigerant gas supply process.

Description

  The present invention relates to a vapor deposition technique and a technique of a vapor deposition apparatus used therefor, and particularly relates to a technique effective when applied to a film forming process for forming a vapor deposition film on a substrate.

  Japanese Patent Laying-Open No. 2004-214185 (Patent Document 1) discloses a vapor deposition apparatus that cools a radiation blocking body by providing a cooling body in contact with the radiation blocking body provided on a crucible and flowing a coolant through the cooling body. Is described.

JP 2004-214185 A

  There is a technique in which a substrate to be processed and an evaporation source are arranged in a vacuum chamber, and a deposited film is formed on the substrate. Such a film forming technique is applied to a process of forming an electrode made of a metal film in a method of manufacturing a flat panel display (FPD) such as an organic EL (Electro Luminescence) display. In the vapor deposition method, vapor deposition or sublimation is performed by heating a vapor deposition material stored in a crucible provided in an evaporation source (hereinafter, vaporization or sublimation is referred to as gasification). Then, the vaporized vapor deposition material is transported to an object to be processed (for example, a vapor deposition film forming region of the substrate) arranged outside the evaporation source, and solidified on the surface of the object to be processed, thereby forming a vapor deposition film.

  In the above-described vapor deposition method, it is necessary to once cool the evaporation source at the time of replacement of the vapor deposition material or maintenance of the vapor deposition apparatus, replace the vapor deposition material, and then raise the temperature to the vapor deposition temperature (process temperature) again. In this evaporation source cooling process, for example, a heating unit such as a heater for heating the crucible is stopped and cooling is performed by natural cooling, but it takes a long time to cool down until the temperature of the crucible reaches the temperature at the time of maintenance. Cost. In particular, when the crucible is cooled in the vacuum chamber, it takes a long time, for example, about 10 hours because of the poor heat transfer efficiency during natural cooling. Therefore, a vapor deposition film can be formed efficiently by reducing this cooling time.

  Here, around the crucible, a heat retaining portion (reflecting plate) called a reflector is disposed from the viewpoint of improving the heat retaining efficiency of the crucible. In the step of forming the vapor deposition film, the heat retention efficiency of the crucible can be improved by reflecting the radiant heat from the crucible and the heating unit for heating the crucible by the reflector. However, in the cooling process, the reflector becomes a factor that hinders the cooling of the crucible. Therefore, the inventors of the present application have studied the configuration for cooling the reflector in the cooling process and shortened the cooling time, and have found the following problems.

  That is, although the structure which attaches a cooling body to a reflector and cools a reflector was examined, the cooling time may not be shortened enough only by attaching a cooling body to a reflector. For example, when the contact area between the cooling body and the reflector is small, there may be a case where sufficient heat exchange cannot be performed even if a coolant flows through the cooling body. In addition, for example, when a gas is flowed as a coolant to a cooling body heated to a high temperature in the process of forming a vapor deposition film, the cooling rate is reduced when the temperature difference between the coolant and the cooling body is small because the heat capacity of the gas is small. On the other hand, when a liquid such as water is flown as a refrigerant through a cooling body heated to a high temperature in the process of forming a vapor deposition film, the refrigerant evaporates all at once in the cooling body, and a large pressure is applied in the refrigerant supply path to cool the cooling body. The durability of the reflector attached to the body is reduced. Further, depending on the position where the cooling body is attached, the cooling body becomes a factor that hinders the heat retaining function of the reflector in the process of forming the vapor deposition film. Therefore, when cooling the reflector, a technique for efficiently cooling the reflector is required as long as the heat retaining function of the reflector is not impaired.

  This invention is made | formed in view of the said subject, The objective is to provide the technique which can shorten the cooling time of an evaporation source.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  That is, the vapor deposition method according to a typical embodiment of the present invention includes: (a) a crucible for storing a vapor deposition material, a heating unit for heating the crucible, and the vapor deposition material gasified in the crucible on the workpiece. A step of disposing an evaporation source including a nozzle for discharging toward the surface of the crucible and a reflector disposed around the crucible and an object to be processed in a vacuum chamber. And (b) heating the vapor deposition material stored in the crucible by the heating unit to generate a vapor deposition material gas that is gasified at a first temperature to form a vapor deposition film on the object to be processed. Contains. Moreover, (c) After the said (b) process, the process of cooling the said crucible and the said vapor deposition material is included. Here, the reflector includes a first surface facing the crucible, a second surface located on the opposite side of the first surface, and a cooling body fixed to the second surface side with respect to the first surface. ing. In the step (c), (c1) a step of flowing a first refrigerant made of gas to the cooling body, (c2) after the step (c1), the cooling body is made of liquid, and the first A step of flowing a second refrigerant having a heat capacity larger than that of the first refrigerant.

  The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

  That is, the cooling time of the evaporation source can be shortened.

It is explanatory drawing which shows the outline | summary of the manufacturing flow of the organic electroluminescent display apparatus which is one embodiment of this invention. It is an expanded sectional view which shows the general | schematic structure of the organic EL element of the organic EL display apparatus manufactured by the flow shown in FIG. It is explanatory drawing which shows the outline | summary of the whole structure of the vacuum evaporation system which is one embodiment of this invention. It is sectional drawing which shows the whole structure in the film-forming chamber shown in FIG. It is sectional drawing which expands and shows the evaporation source shown in FIG. Process flow of vapor deposition method using vapor deposition apparatus and evaporation source shown in FIGS. 3 to 5, temperature profile of crucible in each process, ON / OFF of heating unit in each process, and presence / absence of refrigerant supply to reflector in each process It is explanatory drawing which shows. It is explanatory drawing which shows the temperature profile of the crucible in the cooling process which is the 1st-3rd comparative example with respect to one Embodiment and embodiment of this invention. It is explanatory drawing which shows typically the detailed structure of the reflector shown to FIG. 4 and FIG. It is an expanded sectional view which shows the positional relationship of the reflector shown in FIG. 8, and the crucible shown in FIG. It is a perspective view which shows the structure of the cooling body which is a modification with respect to FIG. It is an expanded sectional view which shows the structure of the cooling body which is a modification with respect to FIG. It is explanatory drawing which shows typically the path | route of the refrigerant | coolant liquid which is a modification with respect to FIG. It is explanatory drawing which shows typically the path | route of the refrigerant | coolant liquid which is a modification with respect to FIG. It is sectional drawing which shows the modification of the evaporation source shown in FIG.

<Description format in this application>
In the following embodiments, when it is necessary for the sake of convenience, the description will be divided into a plurality of sections or embodiments. However, unless otherwise specified, they are not irrelevant to each other. There are some or all of the modifications, details, supplementary explanations, and the like.

  Further, in the following embodiments, when referring to the number of elements (including the number, numerical value, quantity, range, etc.), especially when clearly indicated and when clearly limited to a specific number in principle, etc. Except, it is not limited to the specific number, and may be more or less than the specific number.

  Furthermore, in the following embodiments, the constituent elements (including element steps and the like) are not necessarily indispensable unless otherwise specified and apparently essential in principle.

  Similarly, in the following embodiments, when referring to the shape, positional relationship, etc., of components, etc., unless otherwise specified, and in principle, it is considered that this is not clearly the case, it is substantially the same. Including those that are approximate or similar to the shape. The same applies to the above numerical values and ranges.

  In all the drawings for explaining the embodiments, the same members are denoted by the same reference symbols in principle, and the repeated explanation thereof is omitted. In order to make the drawings easy to understand, even a plan view may be hatched.

  In addition, before describing the present invention in detail, the meaning of terms in the present application will be described as follows.

  Gasification refers to phase transition to the gas phase by heating a solid or liquid phase material. The phase transition to the gas phase includes vaporization (phase transition from the liquid phase to the gas phase) and sublimation (phase transition from the solid phase to the gas phase without passing through the liquid phase). When describing as vaporization, it is used to mean vaporization or sublimation. A material that is vaporized by vaporization is called a vaporization material, and a material that is vaporized by sublimation is called a sublimation material.

  Vapor deposition, a vapor deposition method, or vapor deposition treatment refers to forming a film by taking out a material gas vaporized in a heating container to the outside of the heating container and solidifying it on the surface of an object to be processed. A film formed by vapor deposition is called a vapor deposition film, a material that is a raw material of the vapor deposition film is called a vapor deposition material, and a vaporized vapor deposition material is called a vapor deposition material gas.

  The evaporation source is a device that vaporizes the vapor deposition material and extracts the vapor deposition material gas. Therefore, the evaporation source includes a heating container for storing the vapor deposition material and a take-out port for taking out the vapor deposition material gas.

  Moreover, a vapor deposition apparatus means the apparatus which performs vapor deposition processing to to-be-processed objects, such as a board | substrate, for example. Therefore, the vapor deposition apparatus includes an airtight chamber such as a holding unit that holds an object to be processed and a vacuum chamber that stores the evaporation source and the object to be processed, in addition to the above-described evaporation source.

  Further, in the following embodiments, as an application example of the evaporation source, the evaporation apparatus including the evaporation source, and the evaporation method using the evaporation source, the electrode forming process of the manufacturing method of the organic EL display device specifically examined by the present inventor The case where it is applied to will be described specifically.

<Method for Manufacturing Organic EL Display Device>
FIG. 1 is an explanatory diagram showing an outline of the manufacturing flow of the organic EL display device of the present embodiment. 2 is an enlarged cross-sectional view showing a schematic structure of an organic EL element of the organic EL display device manufactured by the flow shown in FIG.

  As shown in FIG. 1, the manufacturing method of the organic EL display device according to the present embodiment includes a substrate preparation step and an organic EL element formation step of forming an organic EL element on the substrate. In addition, the organic EL element forming step includes an organic layer forming step and a second electrode forming step. Briefly described with reference to FIG. 2, in the substrate preparation step (see FIG. 1), a substrate (glass substrate) 1 having a front surface 1a located on the display surface side and a back surface 1b opposite to the front surface 1a is prepared. For example, a plurality of active elements made of TFT (Thin Film Transistor) or the like are formed in an array on the back surface 1b (not shown). Next, in the first electrode formation step (see FIG. 1), the conductive film 3 serving as, for example, the anode of the organic EL element 2a is formed on the back surface 1b of the substrate 1 (on the active element such as a TFT). In the element structure called bottom emission, since the conductive film 3 is formed on the display surface side of the organic EL element 2a, it is made of a material such as ITO (Indium Tin Oxide) that is transparent to visible light. In the element structure called top emission, the second electrode side is the display surface. Therefore, the conductive film 3 may be formed of a laminated film of an aluminum alloy film having a high reflectance and an ITO film having a high hole injection property. Next, in the organic layer forming step (see FIG. 1), the organic layer 4 is formed on the conductive film 3. The organic layer 4 is a laminated film in which organic films having different functions such as a hole transport layer 4a, a light emitting layer 4b, and an electron transport layer 4c are sequentially laminated. Next, in the second electrode formation step (see FIG. 1), a conductive film 5 is formed on the organic layer 4 as an electrode having a polarity (for example, a cathode) opposite to that of the conductive film 3. The conductive film 5 is made of, for example, a metal thin film such as aluminum (Al) in the bottom emission structure and silver (Ag) / magnesium (Mg) alloy in the top emission structure.

  As described above, the organic EL element 2a has a structure in which the organic layer 4 is sandwiched between the anode (conductive film 3) and the cathode (conductive film 5), and the current flows from the cathode and the anode to the organic layer 4 respectively. Inject electrons and holes. The injected electrons and holes pass through the hole transport layer 4a or the electron transport layer 4c, and are combined in the light emitting layer 4b. Then, the light emitting material of the light emitting layer 4b is excited by the energy of the coupling, and light is generated when returning from the excited state to the ground state again. A plurality of such organic EL elements 2a are formed on the back surface 1b of the substrate 1, and each of the organic EL elements 2a or a combination of the plurality of organic EL elements 2a serves as a display device. Two pixels are formed.

  Here, among the laminated films constituting the organic EL element 2a, the organic layer 4 and the conductive film 5 are vapor deposition films on the substrate 1 by disposing the substrate 1 to be processed and the evaporation source in a vacuum chamber. An organic layer 4 and a conductive film 5 are formed. That is, the organic layer 4 and the conductive film 5 are formed by a so-called vacuum deposition method (vacuum deposition method).

<Overall configuration of vacuum evaporation system>
Next, the overall configuration of the vacuum deposition apparatus used in the organic layer forming step and the second electrode forming step shown in FIG. 1 and the process flow of the organic layer 4 and conductive film 5 forming step shown in FIG. 2 will be described. FIG. 3 is an explanatory diagram showing an outline of the overall configuration of the vacuum vapor deposition apparatus of the present embodiment.

A vapor deposition apparatus (vacuum vapor deposition apparatus) 100 shown in FIG. 3 includes a delivery chamber 101 that delivers a substrate 1, a plurality of deposition chambers 102 that are processing chambers for forming a deposition film, and a substrate in a plurality of deposition chambers. It has a transfer chamber 103 that distributes and transfers 1. FIG. 3 illustrates a configuration in which a plurality of units (three in FIG. 3) including a plurality of film formation chambers 102 and transfer chambers 103 are connected via the delivery chamber 101. Each of the delivery chamber 101, the transfer chamber 103, and the film formation chamber 102 is connected to an exhaust device (not shown) such as a vacuum pump, and is an airtight chamber that can be maintained in a reduced pressure state. In particular, the film formation chamber 102 that performs the vacuum deposition process is a vacuum chamber that can maintain the pressure in the chamber in a reduced pressure state (so-called high vacuum state) of, for example, about 10 ⁻³ Pa to 10 ⁻⁵ Pa.

Among the plurality of delivery chambers 101, the delivery chamber 101 on the entrance side is a loader unit 101a. For example, the substrate 1 on which the conductive film 3 shown in FIG. 2 is formed is carried into the loader unit 101a. In the transfer chamber 103, for example, a robot 103a is arranged as a substrate transfer device, and the substrate 1 is transferred by the robot 103a from the delivery chamber 101 (loader unit 101a) to each film forming chamber 102. In each film forming chamber 102, an evaporation source 10 provided with a vapor deposition material (not shown in FIG. 3) that is a raw material of the organic layer 4 or the conductive film 5 shown in FIG. 2 is arranged, for example, 10 ⁻³ Pa. Under vacuum conditions of about 10 ⁻⁵ Pa, vapor deposited films are sequentially stacked. Specifically, first, in the first film formation chamber 102, the organic layer 4 that is a vapor deposition film to be the hole transport layer 4a is formed on the conductive film 3 that is the anode (first electrode) shown in FIG. To do. The substrate 1 after film formation is taken out to the transfer chamber 103 by the robot 103 a and then transferred to the second film formation chamber 102. In the second film formation chamber 102, the organic layer 4 which is a vapor deposition film to be the light emitting layer 4b is formed on the hole transport layer 4a shown in FIG. The substrate 1 after film formation is taken out to the transfer chamber 103 by the robot 103 a and then transferred to the third film formation chamber 102. In the third film formation chamber 102, the organic layer 4 which is a vapor deposition film to be the electron transport layer 4c is formed on the light emitting layer 4b shown in FIG. The substrate 1 after film formation is taken out to the transfer chamber 103 by the robot 103 a and then transferred to the fourth film formation chamber 102. Then, in the fourth film formation chamber 102, the conductive film 5 which is a vapor deposition film serving as a cathode (second electrode) is formed on the electron transport layer 4c shown in FIG. Then, the substrate 1 on which the conductive film 5 has been formed is transported by the robot 103a to the delivery chamber 101 on the outlet side, which is the unloader unit 101b, and further subjected to a sealing process for the purpose of protection from moisture and oxygen in the atmosphere. Thus, the organic EL display device 2 shown in FIG. 2 is obtained. In the sealing process, the sealing substrate 7 is disposed on the organic EL element 2 a with the sealing material 6 interposed therebetween.

<Configuration of deposition chamber and evaporation source>
Next, the configuration of the deposition chamber 102 and the evaporation source 10 disposed in the deposition chamber 102 shown in FIG. 3 will be described. 4 is a cross-sectional view showing the overall configuration of the film forming chamber shown in FIG. 3, and FIG. 5 is an enlarged cross-sectional view showing the evaporation source shown in FIG.

As shown in FIG. 4, the film forming chamber 102 is connected to a vacuum pump VP and connected to an exhaust path (exhaust pipe) VL for discharging the gas in the film forming chamber 102. A valve V1 is disposed between the vacuum pump VP and the film forming chamber 102. When the valve V1 is opened, the pressure in the film forming chamber 102 is, for example, a reduced pressure state of about 10 ⁻³ Pa to 10 ⁻⁵ Pa (so-called The pressure can be reduced until a high vacuum state is reached. That is, the film formation chamber 102 is a vacuum chamber. In the film forming chamber 102, an evaporation source 10 that discharges the vaporized vapor deposition material gas toward the substrate 1 and a substrate holder 21 that holds the substrate 1 are disposed.

  From the surface 11 a of the housing 11 of the evaporation source 10, a plurality of nozzles 12, which are outlets for the vapor deposition material gas 30 a, are exposed from the housing 11. On the other hand, the substrate holding unit 21 holds the substrate 1 and a mask (evaporation mask) 22. The substrate 1 is disposed such that a back surface 1b, which is a surface on which a vapor deposition film is formed, faces a surface 11a, which is a surface on which a vapor deposition material gas discharge port of the evaporation source 10 is disposed, via a mask 22. In addition, a plurality of openings 22a are formed in the mask 22 corresponding to the positions where the organic EL elements 2a shown in FIG. 2 are formed, and the vapor deposition film forming region of the substrate 1 is formed from the mask 22 in the openings 22a. Exposed. In addition, the positional relationship between the substrate 1 and the evaporation source 10 is such that the back surface 1b of the substrate 1 faces the surface 11a, which is an arrangement surface of the vapor deposition material gas discharge port (nozzle 12), of the evaporation source 10 through the mask 22. What is necessary is just and it is not limited to the aspect shown in FIG. FIG. 4 shows a method called a face-down deposit method in which a plurality of nozzles 12 are arranged on the surface 11a which is the upper surface of the evaporation source 10. In addition to the mode shown in FIG. 4, as a modification, the present invention is applied to a face-up deposit method in which the nozzle 12 is disposed on the lower surface side of the evaporation source 10, or a side deposit method in which the nozzle 12 is disposed on the side surface side of the evaporation source 10. be able to.

  The evaporation source 10 includes a crucible 13 that is a heating container for heating the vapor deposition material 30. In addition, around the crucible 13, a heating unit (heater) 14 that heats the vapor deposition material 30 disposed inside the crucible 13 is provided. Further, around the crucible 13, a reflector (thermal insulation section) 15 that improves the thermal insulation efficiency of the crucible 13 is disposed.

  As shown in FIG. 5, the housing 11 included in the evaporation source 10 includes a lid portion 11c and a main body portion 11d. The lid portion 11c and the main body portion 11d are fixed by fastening means such as screws (not shown). The crucible 13, the heating part 14, and the reflector 15 are accommodated in the main body part 11d, and these members can be taken out by removing the lid part 11c. Further, in the present embodiment, since the surface 11a facing the substrate 1 shown in FIG. 4 is disposed on the upper surface side of the housing 11, an opening 11e is formed in the lid 11c, and the nozzle 12 is formed in the opening 11e. Is exposed.

  The crucible 13 includes a lid portion 13c and a main body portion 13d. The lid portion 13c and the main body portion 13d are fixed by fastening means such as screws (not shown). The vapor deposition material 30 is stored in the bottom of the main body 13d. For example, if the lid 13c is removed, the vapor deposition material 30 can be taken out of the crucible 13 and exchanged. Further, when the lid portion 13c and the main body portion 13d are fixed in an overlapped state, the inside of the crucible 13 becomes a sealed space except for the opening portion 13e that is an outlet for the vapor deposition material gas 30a. In the present embodiment, an example of a structure in which the vapor deposition material gas 30a is taken out from the upper side of the crucible 13 is shown, so the opening 13e is formed in the lid portion 13c of the crucible 13. Further, in the present embodiment, an example of a structure in which the vapor deposition material gas 30a is discharged from the opening 13e of the crucible 13 toward the substrate 1 is shown, and thus the opening 13e is an outlet for the vapor deposition material gas 30a. A nozzle 12 is attached. The nozzle 12 is disposed at a position overlapping the opening 11e formed in the lid 11c of the housing 11, and the nozzle 12 is exposed at the opening 11e. The structure of the evaporation source 10 is not limited to the embodiment shown in FIGS. 4 and 5, and various modifications can be applied. However, in order to make it easier to understand the operation in each step of the vapor deposition method described later, A simplified structure is shown.

  In addition, the heating unit 14 that heats the vapor deposition material 30 and the crucible 13 is disposed so as to surround the periphery of the crucible 13. In the present embodiment, the heating unit 14 is a heater that heats the vapor deposition material 30 and the crucible 13 by, for example, a Joule heating method. 4 and 5 show an example in which the heating unit 14 is arranged along the side surface of the crucible 13, but the arrangement of the heating unit 14 is not limited to the examples shown in FIGS. The heating unit 14 can also be arranged on the lid 13c of the crucible 13 and below the crucible 13. 4 and 5 show an example in which a coil-shaped heater is used as the heating unit 14, but the configuration of the heating unit 14 is not limited to the example shown in FIGS. 4 and 5; The heater (plate heater) can be arranged around the crucible 13.

Moreover, the vapor deposition material 30 is a raw material of the vapor deposition film formed on the substrate 1, and is made of, for example, an organic material constituting the organic layer 4 shown in FIG. 2 or a metal material constituting the conductive film 5. When the vapor deposition material 30 is heated by the heating unit 14 provided in the evaporation source 10, the vapor deposition material 30 is vaporized (vaporized or sublimated) to become a vapor deposition material gas 30a. When the vapor deposition material 30 is gasified, the pressure in the crucible 13 becomes, for example, about 10 ⁰ Pa to 10 ¹ Pa. For this reason, the vapor deposition material gas 30a is taken out of the evaporation source 10 via the opening 11e formed in the crucible 13 and the nozzle 12 due to the pressure difference between the inside and outside of the crucible 13 and is disposed opposite to the nozzle 12. It is released toward 1.

  A reflector 15 that improves the heat retention efficiency of the crucible 13 is disposed around the crucible 13 and the heating unit 14. The reflector 15 is made of, for example, a plurality of metal plates, and is disposed so as to surround the crucible 13 except on the opening 13e. Further, at least a surface (inner surface) facing each of the metal plates is subjected to mirror finishing. The reflector 15 has a function of reflecting the radiant heat from the crucible 13 and the heating unit 14 and improving the heat retention efficiency of the crucible 13 disposed inside the reflector 15. However, the reflector 15 is mirror-finished on the surface facing the crucible 13. By applying, the reflection efficiency (heat retention efficiency) can be improved. Moreover, since the reflector 15 reflects the radiant heat from the crucible 13 or the heating unit 14, the reflector 15 functions as a protective member that suppresses the occurrence of distortion or melting due to the radiant heat in the member outside the reflector 15 (for example, the housing 11). It has.

  Here, in the present embodiment, a cooling body is attached to the reflector 15, and a refrigerant supply path RFin and a refrigerant discharge path RFout are connected to each of the cooling bodies. The reason why the cooling body is attached to the reflector 15 and the detailed structure of the reflector 15 will be described after the outline of the vapor deposition method using the vapor deposition apparatus of the present embodiment.

<Vapor deposition method>
Next, the vapor deposition method of this Embodiment using the vapor deposition apparatus and evaporation source shown in FIGS. 3-5 is demonstrated. 6 shows a process flow of the vapor deposition method using the vapor deposition apparatus and the evaporation source shown in FIGS. 3 to 5, a temperature profile of the crucible in each process, ON / OFF of the heating part in each process, and a reflection to the reflector in each process. It is explanatory drawing which shows the presence or absence of refrigerant supply.

  As shown in FIG. 6, the vapor deposition method of the present embodiment forms a vapor deposition preparation process for preparing a vapor deposition film on the substrate 1 shown in FIG. 4, a vapor deposition process for forming a vapor deposition film on the substrate 1, and forms a vapor deposition film. After that, a cooling process for cooling the crucible 13 and the vapor deposition material shown in FIG. 4 and a maintenance process for maintaining the vapor deposition apparatus and the evaporation source after the cooling process are provided.

First, in the vapor deposition preparation step, preparation for forming a vapor deposition film on the substrate 1 shown in FIG. 4 is performed. Specifically, as shown in FIG. 4, after the deposition material 30 is stored in the crucible 13 of the evaporation source 10, the nozzle 12 is a vacuum chamber so as to face the back surface 1 b of the substrate 1 that is an object to be processed. It is arranged (fixed) in the film formation chamber 102. Thereafter, the valve V1 connected to the exhaust path VL is opened, the gas in the film formation chamber 102 is exhausted by the vacuum pump VP, and the pressure in the film formation chamber 102 is, for example, about 10 ⁻³ Pa to 10 ⁻⁵ Pa. The pressure is reduced until the degree of vacuum is reached. Further, the substrate 1 is transferred from the transfer chamber 103 shown in FIG. 3 into the film forming chamber 102, and the back surface 1 b of the substrate 1 is opposed to the nozzle 12 through the mask 22 by the substrate holding portion 21 as shown in FIG. The substrate 1 is supported. Further, an electric current is passed through the heating unit 14 to heat the crucible 13 and the vapor deposition material 30 disposed in the crucible 13. Thereby, the temperature of the crucible 13 (temperature of the vapor deposition material 30) rises from the temperature T1 to the temperature (process temperature) T2 when forming the vapor deposition film in the vapor deposition process, as shown in FIG. Note that this process requires a time period required for a decompression process in which the inside of the film formation chamber 102 is depressurized to a predetermined degree of vacuum and a temperature raising process in which the temperature of the crucible 13 is increased to a temperature T2. For example, even when the depressurization step and the temperature raising step are performed in parallel, it takes about 5 to 10 hours to move to the vapor deposition step. The time required for the temperature raising process varies depending on the temperature T2, which is the process temperature of the vapor deposition process. For example, when forming a vapor deposition film made of a metal material, the temperature T2 needs to be 500 ° C. or higher, and depending on the type of metal, it needs to be 1000 ° C. or higher.

  Next, in the vapor deposition step shown in FIG. 6, a vapor deposition film is formed on the back surface 1b of the substrate 1 shown in FIG. Specifically, the vapor deposition material 30 is heated inside the evaporation source 10 to generate a vaporized (vaporized or sublimated) vapor deposition material gas 30a. Then, the vapor deposition material gas 30 a is emitted from the nozzle 12 of the evaporation source 10 toward the substrate 1. The vapor deposition material gas 30 a released from the nozzle 12 is blown around the vapor deposition film forming region of the substrate 1 disposed to face the nozzle 12. Then, the vapor deposition material gas 30a is solidified (condensed and precipitated) on the surface of the vapor deposition film forming region whose temperature is lower than the inside of the evaporation source 10, thereby forming a vapor deposition film.

  By the way, in the above-described deposition preparation step, it takes about 5 to 10 hours. Therefore, from the viewpoint of improving the efficiency of the entire vapor deposition method, the substrate 1 is sequentially replaced while maintaining the pressure in the film formation chamber 102 and the temperature of the vapor deposition material 30 shown in FIG. Preferably formed. In other words, after the vapor deposition film is formed on the first substrate 1, the second substrate 1 is replaced with the second substrate 1 while maintaining the pressure in the film formation chamber 102 and the temperature of the vapor deposition material 30. It is preferable to form a deposited film. That is, it is preferable to continuously form the deposited film on the plurality of substrates 1 without stopping the deposition process as much as possible.

  However, there is a limit to the number of substrates 1 that can be processed continuously, and the deposition process may be stopped. For example, when gasification of the vapor deposition material 30 shown in FIG. 4 progresses and the remaining amount decreases, it is necessary to replace it with a new vapor deposition material 30. In this case, since it is necessary to open the lid 13c of the crucible 13 shown in FIG. 5 and to arrange a new vapor deposition material 30, it is difficult to maintain the pressure in the film formation chamber 102 and the temperature of the vapor deposition material 30. is there. In addition, the vapor deposition process may be stopped due to some trouble. In this case, depending on the cause of the problem, it is difficult to maintain the pressure in the film formation chamber 102 and the temperature of the vapor deposition material 30. In addition, the vapor deposition process needs to be stopped when each member in the film formation chamber 102 is maintained. For example, if the time of the vapor deposition process becomes long, the vapor deposition material gas 30a may be deposited and deposited in the evaporation source 10 or the film forming chamber 102. If the deposit of the vapor deposition material 30 adhering in the evaporation source 10 or the film formation chamber 102 increases, it becomes an obstructive factor when forming the vapor deposition film, and therefore it is necessary to periodically remove the deposit. For this reason, in a maintenance process shown in Drawing 6, a vapor deposition process is stopped and the above work (maintenance work) is performed.

  In the maintenance process shown in FIG. 6, since the maintenance work in which it is difficult to maintain the pressure in the film forming chamber 102 and the temperature of the vapor deposition material 30 shown in FIG. 4 as described above is performed, the maintenance process shown in FIG. The cooling process (refer FIG. 6) which reduces the temperature of the crucible 13 shown in FIG. Hereinafter, a detailed embodiment for shortening the cooling time in the cooling process of the present embodiment shown in FIG. 6 will be described. 6 is taken out from the film formation chamber 102 (see FIG. 4) into the transfer chamber 103 (see FIG. 3) before the cooling step. It is. Below, the detail of the cooling process after taking out the board | substrate 1 from the film-forming chamber 102 is demonstrated.

<Details of cooling process>
FIG. 7 is an explanatory view showing the temperature profile of the crucible in the cooling process, which is the first to third comparative examples for the present embodiment and the present embodiment. 8 is an explanatory view schematically showing the detailed structure of the reflector shown in FIGS. 4 and 5. FIG. 9 is an enlarged cross-sectional view showing the positional relationship between the reflector shown in FIG. 8 and the crucible shown in FIG. Note that the vapor deposition apparatus used in the first and second comparative examples shown in FIG. 7 is the same as the present embodiment except that the cooling body is not attached to the reflector, and thus illustration is omitted. Moreover, since the vapor deposition apparatus used for the 3rd comparative example shown in FIG. 7 is the same as this Embodiment except that the refrigerant | coolant which flows into a reflector is only refrigerant gas, illustration is abbreviate | omitted.

  In the cooling step shown in FIG. 6, the heating unit 14 shown in FIG. 4 is stopped, and the temperature of the crucible 13 is cooled from the temperature T2 that is the process temperature to the temperature T1 at which maintenance work can be performed. The temperature T1 can be the same as, for example, room temperature (atmosphere temperature around the vapor deposition apparatus), but an impurity film such as an oxide film is formed on each member such as the evaporation source 10 (see FIG. 5) when performing maintenance work. However, it is not limited to this, as long as it is possible to suppress the formation of and to perform the work. Therefore, in FIG. 6, the temperature at the start of heating in the deposition preparation step and the temperature at the end of the cooling step in the cooling step are shown as temperature T1, respectively, but this temperature T1 is strictly the same temperature. It is not necessary to have a certain width. For example, it is higher than room temperature and can be about 30 ° C to 60 ° C. Further, the temperature T2 varies depending on the gasification temperature of the vapor deposition material 30 (see FIG. 5), but may be, for example, about 400 ° C. to over 1000 ° C.

  Here, the following aspects can be considered as a cooling process which is a first comparative example for the present embodiment. That is, immediately after the start of the cooling process, the heating unit 14 (see FIG. 5) is immediately stopped, and the temperature of the crucible 13 (FIG. 5) is lowered by natural cooling. In this case, as shown in the cooling curve P2 shown in FIG. 7, the temperature of the crucible 13 can be cooled to the temperature T1 in about 4 to 8 hours, for example. However, in the first comparative example, immediately after the start of cooling, the vaporization of the vapor deposition material 30 shown in FIG. 5 is not stopped, and the temperature of the crucible 13 rapidly decreases. There exists a problem that the vapor deposition material 30 precipitates and adheres easily to the wall surface of this and the inner surface of the cover part 13c. Thus, when the vapor deposition material 30 precipitates on the wall surface in the crucible 13 or the inner side surface of the lid portion 13c, it becomes an obstructive factor for forming a vapor deposition film having a uniform film quality in the vapor deposition step shown in FIG. Further, when the vapor deposition material 30 is deposited at the joint between the lid portion 13c and the main body portion 13d, this deposit functions as an adhesive, making it difficult to remove the lid portion 13c from the main body portion 13d. In addition, when removing the precipitate, it is necessary to remove the precipitate by machining, which makes the maintenance work complicated. Thus, in the cooling step, it is necessary to suppress the deposition material 30 from being deposited on the wall surface in the crucible 13 or the inner side surface of the lid portion 13c.

  Therefore, as an embodiment for suppressing the deposition of the vapor deposition material 30 in the cooling process, a cooling process which is a second comparative example with respect to the present embodiment can be considered. That is, as shown in FIG. 5, the heating unit 14 is divided into a plurality of blocks, and each block can be independently turned on and off. In the example shown in FIG. 5, the upper block 14 a arranged around the lid portion 13 c of the crucible 13 and the lower block 14 b arranged around the vapor deposition material 30 arranged in the crucible 13 are divided. In the cooling process, after the cooling process is started, the lower block 14b of the heating unit 14 is stopped, but the upper block 14a is not stopped. That is, while the heating by the upper block 14a is continued, the temperature of the vapor deposition material 30 reaches a temperature T3 (see FIG. 7; for example, 800 ° C. to 900 ° C.) at which the vaporization of the vapor deposition material 30 is stopped or reduced. The crucible 13 and the vapor deposition material 30 are gradually cooled. Thereafter, the upper block 14a is also stopped and cooled by natural cooling until the entire temperature of the crucible 13 reaches the temperature T1. In this case, since the heating of the lid portion 13c is continued until the vaporization of the vapor deposition material 30 is stopped or sufficiently reduced, it is possible to suppress the vapor deposition material 30 from adhering to the lid portion 13c. However, as shown as a cooling curve P3 in FIG. 7, the cooling rate is slow from the temperature T2 to the temperature T3 (slow cooling period S1). Therefore, after reaching the temperature T3, the upper block 14a is stopped, In the case of the second comparative example that is cooled by cooling, it takes, for example, about 5 hours to 10 hours to reach the temperature T1 that is the end point of the cooling step. Note that it is also the same in this embodiment that the slow cooling period S1 is preferably provided from the viewpoint of suppressing the deposition of the vapor deposition material 30 in the cooling step. Therefore, as shown as a cooling curve P1 in FIG. 7, also in this embodiment, as described above, the temperature of the vapor deposition material 30 is the temperature of the crucible 13 is the temperature T2 (for example, 1000 ° C. to 1100 ° C.). The heating by the upper block 14a of the heating unit 14 is continued until reaching the temperature T3 (see FIG. 7; for example, 800 ° C. to 900 ° C.) at which the conversion is stopped or reduced. That is, the cooling process includes a slow cooling period S1 (slow cooling process). In addition, a slow cooling period S1 is similarly provided in a cooling curve P4 in a third comparative example described later.

  In the first and second comparative examples described above, since the heating unit 14 is stopped and the temperature of the crucible 13 is lowered by natural cooling, the cooling time becomes very long. Therefore, the inventor of the present application arranges a cooling member around the crucible 13 and forcibly cools the crucible 13 with the cooling member until the temperature T1 reaches the temperature T1 shown in FIG. We examined the shortening configuration. Specifically, a cooling body 16 is attached to each of the reflectors 15 shown in FIGS. 4 and 5 as shown in FIG. 8, and the crucible 13 is forcibly cooled by flowing a coolant through the cooling body 15. Hereinafter, the detailed structure of the reflector 15 will be described with reference to FIGS. 8 and 9.

  As shown in FIGS. 8 and 9, a cooling body 16 is fixed to the reflector 15. In the example shown in FIGS. 8 and 9, the cooling body 16 is a pipe made of metal, and is fixed so as to be in contact with the surface 15 b located on the opposite side of the surface 15 a that is the surface facing the crucible 13 of the reflector 15. ing. The method for fixing the cooling body 16 to the reflector 15 is not particularly limited. For example, the cooling body 16 is welded and fixed to the surface 15b of the reflector 15. In this case, since the reflector 15 and the cooling body 16 are prepared separately and then fixed, it can be easily processed. Moreover, since the cooling body 16 and the reflector 15 can be made to contact reliably, the contact area of the cooling body 16 and the reflector 15 can be increased easily. Further, the contact area between the cooling body 16 and the reflector 15 is increased by arranging the cooling body 16 that is a flow path of the refrigerant so as to meander along the surface 15b of the reflector 15 as shown in FIG. Can do. As shown in FIG. 8, the cooling body 16 includes an inlet portion 16a that is a refrigerant supply port and an outlet portion 16b that is a refrigerant discharge port. Further, the refrigerant supply path RFin is connected to the inlet portion 16a, and the refrigerant discharge path RFout is connected to the outlet portion 16b, respectively, so that the refrigerant can be supplied into the cooling body 16 in the cooling process. Yes. Specifically, each of the refrigerant supply path RFin and the refrigerant discharge path RFout shown in FIG. 8 is a pipe made of metal, for example, and communicates with the inside and outside of the film forming chamber 102 which is a vacuum chamber. Further, the refrigerant supply path RFin is a supply source of refrigerant liquid via a valve VR1 to a supply source (refrigerant supply reduction) TG which is a supply source of refrigerant gas via a valve VG1 outside the film forming chamber 102. Each is connected to a supply source (refrigerant supply reduction) TR. The valve VG1 and the valve VR1 constitute a so-called three-way valve, and have a structure capable of switching and supplying the refrigerant supply path RFin refrigerant gas or refrigerant liquid. In addition, the refrigerant discharge path RFout is connected to the valves VG2 and VR2 constituting the three-way valve outside the film forming chamber 102, and the refrigerant whose heat exchange has been completed by the cooling body 16 flows from the valve VG2 or the valve VR2. It is discharged out of the road.

  In the cooling process using the reflector 15 to which the cooling body 16 shown in FIG. 8 is attached, in the cooling process, after the slow cooling period S1 (see FIG. 7), the coolant is supplied to the cooling body 16 and Pour refrigerant. As a result, the temperature of the reflector 15 is lowered via the cooling body 16, so that the reflector 15 shown in FIG. 9 absorbs radiant heat (residual heat after the heating unit 14 is stopped) from the crucible 13 and the heating unit 14. The cooling rate of the crucible 13 shown in FIG. That is, by causing the coolant to flow through the cooling body 16, the crucible 13 can be forcibly cooled by causing the reflector 15 to function as a cooling plate.

Here, although the aspect which uses only any one among refrigerant gas and refrigerant liquid as a refrigerant | coolant can be considered, the following subjects arise. For example, when only a refrigerant gas such as nitrogen (N ₂ ) gas or air is used, the cooling time may not be sufficiently shortened because the heat capacity of the gas is small. In particular, when the temperature of the crucible 13 (see FIG. 9) decreases and the temperature difference between the refrigerant gas and the crucible 13 becomes smaller, the cooling effect by the refrigerant gas is extremely reduced. For this reason, when only the refrigerant gas is used, for example, as shown in FIG. 7 as a cooling curve P4 as a comparative example, the cooling time until reaching the temperature T1 from the temperature T2 is compared with the cooling curves P2 and P3. Although it can be shortened, the degree of time reduction is limited.

  On the other hand, when only a refrigerant liquid having a larger heat capacity than nitrogen gas or air, such as water, is used, the cooling effect of the refrigerant liquid is unlikely to decrease even if the temperature difference between the refrigerant liquid and the crucible 13 (see FIG. 9) is small. Compared with the case where refrigerant gas is used, the cooling time can be greatly shortened. However, when the refrigerant liquid is caused to flow through the cooling body 16 heated to a high temperature in the vapor deposition step (see FIG. 6), a large pressure is applied to the cooling body 16 because the refrigerant liquid evaporates all at once in the cooling body 16. And the pressure resulting from the refrigerant liquid causes damage to the reflector 15 to which the cooling body 16 is attached. For example, if the connecting portion that fixes the cooling body 16 to the reflector 15 is damaged, the cooling efficiency is reduced. Further, for example, when the reflector 15 is deformed by pressure or thermal shock caused by the refrigerant liquid, it becomes a factor that hinders the reflection function (heat retention function) of the reflector 15 in the vapor deposition process (see FIG. 6).

  Based on the problems of the comparative examples described above, the inventor of the present application has studied the technology for suppressing damage to the reflector 15 and shortening the cooling time, and found the configuration of the present embodiment. That is, the cooling step in the vapor deposition method of the present embodiment includes a step of flowing a refrigerant made of gas (refrigerant gas) through the cooling body 16 (refrigerant gas supply period S2 shown in FIG. And flowing a refrigerant (refrigerant liquid) having a larger heat capacity than the refrigerant gas (refrigerant liquid supply period S3 shown in FIG. 7). Specifically, in the refrigerant gas supply period S2 (see FIG. 7), the valve VG1 shown in FIG. 8 is opened and the valve VR1 is closed, so that a refrigerant gas such as nitrogen gas or air flows through the refrigerant supply path RFin. . The temperature of the crucible 13 (see FIG. 9) in the refrigerant gas supply period S2 is sufficiently large (for example, about 500 ° C. to 900 ° C.) with respect to the temperature of the refrigerant gas (for example, about 25 ° C.). Even so, a decrease in the cooling effect can be suppressed. For this reason, as shown as a cooling curve P1 in FIG. 7, the temperature of the crucible 13 can reach the temperature T4 earlier than the cooling curve P2 and the cooling curve P3 which are comparative examples. The temperature T4 is the temperature (set temperature) of the crucible 13 when the type of refrigerant supplied to the cooling body 16 is switched from refrigerant gas to refrigerant liquid, and is about 500 ° C., for example. Subsequently, in the refrigerant liquid supply period S3 (see FIG. 7) after the temperature of the crucible 13 reaches the temperature T4, the valve VG1 shown in FIG. 8 is closed and the valve VR1 is opened to enter the refrigerant supply path RFin. For example, a coolant such as water is allowed to flow. At this time, since the temperatures of the reflector 15 and the cooling body 16 are reduced (for example, 500 ° C. or lower), it is possible to suppress the evaporation of the refrigerant liquid in the cooling body 16 at once. For this reason, since the pressure and thermal shock which generate | occur | produce due to evaporation of a refrigerant | coolant liquid can be reduced, damage to the reflector 15 and the cooling body 16 resulting from this can be suppressed. In addition, since the refrigerant liquid having a large heat capacity is used as the refrigerant in the low temperature region where the temperature of the crucible 13 ranges from the temperature T4 to the temperature T1, it is possible to suppress a decrease in the cooling effect. As a result, as shown as a cooling curve P1 in FIG. 7, the cooling time from the temperature T2 to the temperature T1 is significantly shortened compared to the cooling curve P4, for example, cooling is performed in about 2 to 5 hours. The process can be finished. That is, according to the present embodiment, the reflector 15 can be efficiently cooled within a range that does not impair the heat retaining function of the reflector 15.

<Process after cooling process>
After the cooling process is completed, a maintenance process is performed as shown in FIG. In the maintenance process, as described above, for example, replacement of the vapor deposition material 30 shown in FIG. 4 and maintenance of each member in the film forming chamber 102 are performed. Then, the vapor deposition preparation process is performed again to prepare for the next vapor deposition process.

  By the way, in a vapor deposition preparation process, an electric current is sent through the heating part 14 shown in FIG. 4 as mentioned above, and the vapor deposition material 30 arrange | positioned in the crucible 13 is heated. At this time, since the cooling body 16 shown in FIG. 8 is fixed to the reflector 15, if a cooling liquid having a large heat capacity remains in the cooling body 16, the remaining refrigerant liquid inhibits the temperature rise of the crucible 13. It becomes a factor. Therefore, in the present embodiment, after the cooling step and before the temperature raising step for raising the temperature of the crucible 13, gas (purge gas) is supplied to the refrigerant flow path in the cooling body 16, and the cooling body A step (purge step) of discharging the refrigerant liquid remaining in 16 is provided. For example, in the example shown in FIG. 6, the refrigerant gas is supplied before the heating unit is turned on in the vapor deposition preparation step. Thereby, in the process of raising the temperature of the crucible 13, since the gas remaining in the cooling body 16 is a gas having a lower heat capacity than the refrigerant liquid, it is possible to suppress the increase in the temperature raising time. In other words, according to the present embodiment, the cooling time is shortened by cooling with the refrigerant liquid in the cooling process, and the refrigerant liquid remaining in the cooling body 16 is used as the purge gas before the temperature raising process. The temperature raising time can be shortened by the replacement. Note that a gas different from the refrigerant gas can be used as the purge gas for purging with the coolant, but this embodiment shows an embodiment in which the refrigerant gas is also used as the purge gas. By combining the refrigerant gas and the purge gas, the gas supply path can be simplified. After the above, the cycle of the vapor deposition preparation process, vapor deposition process, cooling process, and maintenance process shown in FIG. 6 is repeated.

<Preferred embodiment and modification>
Next, a particularly preferable aspect in the above-described vapor deposition apparatus and vapor deposition method of the present embodiment will be described including modifications. FIG. 10 is a perspective view showing the structure of a cooling body which is a modification to FIG. FIG. 11 is an enlarged cross-sectional view showing the structure of a cooling body which is a modification to FIG. FIG. 12 and FIG. 13 are explanatory diagrams schematically showing the path of the refrigerant liquid that is a modification example of FIG. FIG. 14 is a cross-sectional view showing a modification of the evaporation source shown in FIG.

  First, as shown in FIG. 9, the cooling body 16 is preferably arranged on the surface 15 b side opposite to the surface 15 a of the reflector 15, which is the surface facing the crucible 13. As described above, the surface 15 a has a function of keeping the temperature of the crucible 13 by reflecting the radiant heat from the heating unit 14 and the crucible 13 toward the crucible 13. Since the reflectance of the radiant heat increases as the flatness of the surface 15a, which is a reflection surface, increases, the surface 15a is preferably subjected to, for example, an electrolytic polishing process to be in a mirror state. Here, when the cooling body 16 is fixed to the surface 15 a of the reflector 15, the flatness of the surface facing the crucible 13 is lowered, so that the heat retaining function of the reflector 15 is lowered. Therefore, it is preferable to fix the cooling body 16 at a place other than the surface 15a.

  From the viewpoint of the cooling efficiency of the reflector 15, it is preferable that the contact area between the cooling body 16 and the reflector 15 is wide. For example, simply attaching the cooling body 16 to the side surface between the surface 15a and the surface 15b of the reflector 15 causes the contact area between the cooling body 16 and the reflector 15 to be insufficient, so that the reflector 15 cannot be sufficiently cooled. The reflector 15 is formed so as to increase the area of the surface 15a in order to improve the reflection efficiency. For this reason, the area of the surface 15b located on the opposite side of the surface 15a is also wide like the surface 15a. Therefore, by disposing the cooling body 16 along the surface 15b of the reflector 15, the contact area between the cooling body 16 and the reflector 15 can be increased, which is preferable from the viewpoint of improving the cooling efficiency.

  8 and 9, as an example of the cooling body 16, the pipe fixed so as to meander along the surface 15 b of the reflector 15 has been described. However, as a modification, for example, as illustrated in FIG. Except for the part 16a and the outlet part 16b, a cooling body 16A having a sealed hollow space 16c may be attached along the surface 15b of the reflector 15. In this case, the contact area with the reflector 15 can be further expanded as compared with the cooling body 16 formed of the piping shown in FIG. However, from the viewpoint of suppressing the retention of the refrigerant in the hollow space 16c, a configuration in which the refrigerant flow path meanders along the surface 15b like the cooling body 16 shown in FIG. 8 is preferable. As another modification, a groove 16e is formed in a surface 16d that is a surface facing the surface 15b of the reflector 15 as in the cooling body 16B shown in FIG. 11, and the surface 16d and the surface 15b are in close contact with each other. Thus, the refrigerant flow path can be formed by the groove 16e and the surface 15b of the reflector 15. In this case, the contact area with the reflector 15 can be further expanded than the cooling body 16 shown in FIG. 8, and the retention of the refrigerant can also be suppressed. However, in this case, since the flow path of the refrigerant is formed by bringing the reflector 15 and the cooling body 16 into close contact, from the viewpoint of improving the airtight reliability of the flow path of the refrigerant, the cooling body 16 shown in FIG. In addition, it is preferable that the refrigerant flow path is formed separately from the reflector 15. 8 to 11, the mode in which the cooling bodies 16, 16 </ b> A, and 16 </ b> B formed separately are joined by welding, for example, has been described. However, the coolant channel is formed on the surface 15 b side of the reflector 15. (The illustration is omitted). However, since the surface 15a of the reflector 15 is preferably formed in a mirror shape, the cooling bodies 16, 16A, 16B and the reflector 15 are preferably formed separately from the viewpoint of easy processing. Further, the method of fixing the cooling bodies 16, 16A, 16B to the reflector 15 is not limited to welding, but it is preferable to fix by cooling from the viewpoint of improving the fixing strength and the heat resistance of the bonding material.

  Further, from the viewpoint of suppressing damage due to the thermal cycle at the joint between the cooling bodies 16, 16A, 16B and the reflector 15, the cooling bodies 16, 16A, 16B are made of a material having a linear expansion coefficient close to that of the reflector 15, particularly preferably It is preferable to form the same material as the reflector 15. For example, when the reflector 15 is formed of stainless steel, it is preferable that the cooling bodies 16, 16A, and 16B are also formed of stainless steel. When the reflector 15 is made of a metal material such as molybdenum (Mo), tantalum (Ta), or tungsten (W) from the viewpoint of improving heat resistance, the cooling bodies 16, 16A, and 16B are also made of these metal materials. It is preferable to form by.

  Next, as the gas used as the refrigerant gas in the cooling step shown in FIG. 6, for example, air can be used. From the viewpoint of suppressing oxidation of the refrigerant flow path and improving durability, for example, nitrogen gas or the like can be used. It is preferable to use an inert gas. In addition, the liquid used as the refrigerant liquid in the cooling step shown in FIG. 6 is preferably water from the viewpoint of reducing manufacturing costs. Moreover, a corrosion inhibitor etc. can also be added from a viewpoint of improving durability of the flow path of a refrigerant | coolant.

  Further, as in the modification shown in FIG. 12, the vacuum pump VP2 is connected to the refrigerant gas discharge path, and in the vapor deposition preparation step shown in FIG. 6, before the temperature raising step of the crucible 13 (see FIG. 9), the refrigerant The purge gas remaining in the flow path can be discharged. In this case, since the flow path of the refrigerant in the cooling body 16 is in a reduced pressure state (vacuum state), the temperature raising time can be further shortened as compared with the aspect shown in FIG.

  Further, as in the modification shown in FIG. 13, a cooling device CH that lowers the temperature of the refrigerant liquid after heat exchange is connected to the refrigerant liquid discharge path, and the refrigerant liquid cooled by the cooling device CH is supplied from the supply source TR. It can be set as the structure to do. In this case, for example, the temperature of the refrigerant liquid can be set lower than room temperature (for example, 25 ° C.), so that the temperature difference between the refrigerant liquid and the crucible 13 can be increased also in the refrigerant liquid supply period S3 shown in FIG. it can. For this reason, the cooling time can be further shortened. In addition, the coolant can be saved by circulating the coolant.

  Moreover, in the example shown in FIG. 6 and FIG. 7, the aspect which starts supply of refrigerant gas after completion | finish of slow cooling period S1 (refer FIG. 7) was demonstrated. From the viewpoint of suppressing the deposition material 30 from depositing and adhering to the wall surface in the crucible 13 and the inner side surface of the lid portion 13c shown in FIG. 4, the above aspect is preferable in that the deposition can be more reliably suppressed. Moreover, it can be set as the aspect which starts supply of refrigerant gas during the slow cooling period S1 shown in FIG. 7 as a modification of the aspect shown in FIG. 6 and FIG. 7 (illustration is omitted). In this case, the slow cooling period S1 can be further shortened as compared with the embodiment shown in FIGS. However, in this case, since the vapor deposition material 30 is more easily deposited than the modes shown in FIGS. 6 and 7, it is preferable to supply the refrigerant gas without stopping the upper block 14a of the heating unit 14 shown in FIG. By continuing the heating by the upper block 14a of the heating unit 14 disposed around the region where the vapor deposition material 30 in the crucible 13 is not disposed, the vapor deposition material 30 deposited on the wall surface and the lid 13c in the crucible 13 can be obtained. The amount of precipitation can be reduced.

  Further, as a modification of the evaporation source 10 shown in FIG. 5, a plurality of reflectors 15 may be arranged side by side between the crucible 13 and the wall of the housing as shown in FIG. 14. As described above, the evaporation source 10A in which the plurality of reflectors 15 are arranged side by side can improve the heat retention of the crucible 13 as compared with the evaporation source 10 shown in FIG. That is, of the plurality of reflectors 15, the radiant heat that could not be reflected by the reflector 15 </ b> A disposed on the innermost side (the crucible 13 side) is reflected by the reflector 15 </ b> B disposed on the outer side (housing 11 side) than the reflector 15. Can do. As a result, the heat retention efficiency can be improved according to the number of reflectors 15 arranged side by side. When applying the cooling process described above to the evaporation source 10A, among the plurality of reflectors 15 arranged side by side, the cooling bodies 16, 16A shown in FIGS. It is preferable to attach any of 16B. Of the reflectors 15A, 15B, 15C, and 15D, the reflector 15A has the greatest heat-retaining effect on the crucible 13, and the cooling time can be shortened most by cooling the reflector 15A. In the modification shown in FIG. 14, a plurality of reflectors 15 are arranged between the crucible 13 and the wall of the housing 11 or the lid portion 11 c, respectively, but the coolant supply path RFin and the coolant discharge path RFout are respectively the most crucible 13. It is connected only to the reflector 15A arranged on the side. As a further modification to FIG. 14, the refrigerant supply path RFin and the refrigerant discharge path RFout can be connected to all of the reflectors 15A, 15B, 15C, and 15D. However, if the flow path of the refrigerant in the housing 11 becomes complicated, the vapor deposition step shown in FIG. 6 may have an adverse effect from the viewpoint of keeping the temperature of the crucible 13 constant. For this reason, as shown in FIG. 14, the configuration in which the refrigerant supply path RFin and the refrigerant discharge path RFout are connected only to the reflector 15A simplifies the piping path (refrigerant flow path) in the housing 11 and the cooling time. It is particularly preferable from the viewpoint of shortening.

  Further, in the cooling process shown in FIG. 6, for example, the inside of the film forming chamber 102 shown in FIG. 4 can be performed in a reduced pressure state (vacuum state), but heat exchange between the cooled reflector 15 and the crucible 13 can be performed more efficiently. From the viewpoint of performing, the cooling step (particularly, the refrigerant gas supply period S2 and the refrigerant liquid supply period S3 shown in FIG. 7) is preferably performed by introducing an inert gas such as nitrogen gas into the film forming chamber 102. . As a result, convection of the inert gas introduced into the film forming chamber 102 and the housing 11 occurs, and heat exchange between the reflector 15 and the cooling body 16 and the crucible 13 is performed via the inert gas. As a result, the cooling efficiency is further improved, so that the cooling time can be shortened. Note that in the case where gas is introduced into the film formation chamber 102, time is required for decompressing the film formation chamber 102 (see FIG. 4) in the vapor deposition preparation step shown in FIG. However, in the maintenance process shown in FIG. 6, when it is necessary to open the reduced pressure state in the film formation chamber 102, it is necessary to reduce the pressure regardless of whether or not the inert gas is introduced. A method of introducing an inert gas in the process is effective.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  For example, in the above-described embodiment, the vapor deposition method called the point source method in which the vapor deposition film is formed by using the evaporation source 10 having one nozzle 12 as an aspect of the evaporation source has been described. A vapor deposition method in which a plurality of evaporation sources 10 are arranged side by side in one film formation chamber 102 can be employed. In this case, since the range in which the vapor deposition material gas 30a reaches increases, the efficiency of the vapor deposition process can be improved.

  The present invention can be widely used in products for forming a deposited film such as an organic EL display and lighting, and a deposition apparatus.

1 substrate 1a front surface 1b back surface 2 organic EL display device (display device)
2a Organic EL element 3, 5 Conductive film 6 Sealing material 7 Sealing substrate 4 Organic layer 4a Hole transporting layer 4b Light emitting layer 4c Electron transporting layer 6 Sealing material 7 Sealing substrate 10, 10A Evaporation source 11 Housing 11a Surface 11c Lid 11d Main body 11e Opening 12 Nozzle 13 Crucible 13c Lid 13d Main body 13e Opening 14 Heating unit 14a Upper block 14b Lower blocks 15, 15A, 15B, 15C, 15D Reflectors (thermal insulation, reflector)
15a, 15b Surface 16, 16A, 16B Cooling body 16a Inlet portion 16b Outlet portion 16c Hollow space 16d Surface 16e Groove 21 Substrate holding portion 22 Mask 22a Opening portion 26 Gas 27 Sensor 28 Control portion 30 Deposition material 30a Deposition material gas 100 Deposition device 101 Delivery chamber 101a Loader unit 101b Unloader unit 102 Film forming chamber 103 Transfer chamber 103a Robot (substrate transfer device)
CH Cooling devices P1, P2, P3, P4 Cooling curve RFin Refrigerant supply path RFout Refrigerant discharge path S1 Slow cooling period (slow cooling process)
S2 Refrigerant gas supply period (refrigerant gas supply process)
S3 Refrigerant liquid supply period (refrigerant liquid supply process)
T1, T2, T3, T4 Temperature TG Supply source (refrigerant gas supply source)
TR supply source (refrigerant liquid supply source)
V1, V2, VG1, VG2, VR1, VR2 Valve VL Exhaust path VP, VP2 Vacuum pump

Claims (14)

(A) A crucible for storing a vapor deposition material, a heating unit for heating the crucible, a nozzle for discharging the vapor deposition material gasified in the crucible toward the object to be processed, and a reflector disposed around the crucible Disposing an evaporation source comprising: and an object to be processed in a vacuum chamber;
(B) heating the vapor deposition material stored in the crucible by the heating unit to generate a vapor deposition material gas that is gasified at a first temperature, and forming a vapor deposition film on the object to be processed;
(C) a step of cooling the crucible and the vapor deposition material after the step (b);
Including
The reflector is
A first surface facing the crucible, a second surface located on the opposite side of the first surface, and a cooling body fixed to the second surface side with respect to the first surface,
In the step (c),
(C1) flowing a first refrigerant made of gas through the cooling body,
(C2) After the step (c1), a step of flowing a second refrigerant made of a liquid and having a larger heat capacity than the first refrigerant in the cooling body,
The vapor deposition method characterized by including. The vapor deposition method according to claim 1,
The said cooling body is arrange | positioned along the said 2nd surface of the said reflector, The vapor deposition method characterized by the above-mentioned. In the vapor deposition method of Claim 1 or Claim 2,
The cooling body constitutes a flow path for the first and second refrigerants,
The vapor deposition method, wherein the flow path meanders along the second surface of the reflector. In the vapor deposition method of any one of Claims 1-3,
The said cooling body consists of piping formed separately from the said cooling body, and is being fixed to the said reflector by welding, The vapor deposition method characterized by the above-mentioned. In the vapor deposition method of any one of Claims 1-4,
(D) after the step (c), supplying a purge gas to the flow paths of the first and second refrigerants in the cooling body and discharging the second refrigerant remaining in the cooling body;
(E) a step of raising the temperature of the crucible after the step (d);
The vapor deposition method characterized by including further. In the vapor deposition method of Claim 5,
(F) After the step (d) and before the step (e), the flow paths of the first and second refrigerant in the cooling body are decompressed, and the purge gas remaining in the cooling body is discharged. The process of
The vapor deposition method characterized by including further. In the vapor deposition method of any one of Claims 1-6,
The evaporation source has a casing that covers the crucible, the heating unit, and the reflector, and has an opening through which the nozzle is exposed,
Between the casing and the crucible, a plurality of the reflectors are arranged side by side,
The said cooling body is being fixed to the 1st reflector most arrange | positioned among the said several reflectors at the said crucible side, The vapor deposition method characterized by the above-mentioned. A vacuum chamber, an evaporation source disposed in the vacuum chamber, and a holding unit for holding an object to be processed in the vacuum chamber,
The evaporation source is
A crucible for storing a vapor deposition material, a heating unit for heating the crucible, a nozzle for discharging the vapor deposition material gasified in the crucible toward the object to be processed, and a reflector disposed around the crucible ,
The reflector is
A first surface facing the crucible, a second surface located on the opposite side of the first surface, and a cooling body fixed to the second surface side with respect to the first surface,
The cooling body is
A first refrigerant supply source for supplying a first refrigerant made of gas into the cooling body, and a second refrigerant supply for supplying a second refrigerant made of liquid and having a larger heat capacity than the first refrigerant into the cooling body. A vapor deposition apparatus connected to a source. The vapor deposition apparatus according to claim 8, wherein
The said cooling body is arrange | positioned along the said 2nd surface of the said reflector, The vapor deposition apparatus characterized by the above-mentioned. In the vapor deposition apparatus of Claim 8 or Claim 9,
The cooling body constitutes a flow path for the first and second refrigerants,
The vapor deposition apparatus, wherein the flow path meanders along the second surface of the reflector. In the vapor deposition apparatus of any one of Claims 8-10,
The said cooling body consists of piping formed separately from the said cooling body, and is being fixed to the said reflector by welding, The vapor deposition apparatus characterized by the above-mentioned. In the vapor deposition apparatus of any one of Claims 8-11,
The vapor deposition apparatus, wherein the cooling body is connected to a purge gas supply source that supplies a purge gas into the cooling body. The vapor deposition apparatus according to claim 12, wherein
The vapor deposition apparatus, wherein the cooling body is connected to a decompression pump that discharges a purge gas in the cooling body. In the vapor deposition apparatus of any one of Claims 8-13,
The evaporation source has a casing that covers the crucible, the heating unit, and the reflector, and has an opening through which the nozzle is exposed,
Between the casing and the crucible, a plurality of the reflectors are arranged side by side,
The said cooling body is being fixed to the 1st reflector most arrange | positioned among the said several reflectors at the said crucible side, The vapor deposition apparatus characterized by the above-mentioned.

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