JP2012207263A - Vapor deposition method, and vapor deposition apparatus - Google Patents

Abstract

The cooling time of an evaporation source is shortened.
In a vapor deposition preparation step, a crucible 13 for storing a vapor deposition material 30, a heating unit 14 for heating the crucible 13, and a nozzle 12 for discharging the vapor deposition material 30 gasified in the crucible 13 toward a workpiece, The evaporation source 10 comprising: and the workpiece are placed in a vacuum chamber. Next, the vapor deposition material 30 accommodated in the crucible 13 is heated by the heating unit 14 to generate a vaporized vapor deposition material gas, thereby forming a vapor deposition film on the object to be processed. Next, the gas 26 is supplied into the crucible 13 from the outside of the evaporation source 10 through the nozzle 12, and the heating unit 14 is stopped to cool the crucible 13.
[Selection] Figure 8

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.

  In Japanese Patent Application Laid-Open No. 2008-115416 (Patent Document 1), a reflector for blocking radiant heat from a crucible is moved upward at the end of film formation, and a heater for heating the crucible is stopped to form a film. A vapor deposition method for reducing the cooling time of the crucible after completion is described.

JP 2008-115416 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 general, the evaporation source cooling step and the temperature raising step each require about 5 to 10 hours, and the deposited film can be efficiently formed by reducing the cooling time and the temperature raising time. . In particular, in the cooling process, in order to suppress the deposition material from adhering to the wall surface and lid of the evaporation source (crucible), the heating of the evaporation source by the heater is continued until the temperature of the deposition material reaches the evaporation stop temperature. A so-called slow cooling process of slow cooling is performed, and this slow cooling process is one of the causes of increasing the cooling time.

  As described in Patent Document 1, in the case of a vapor deposition method in which the reflector is moved so that the upper part of the crucible and the lid are kept warm while the lower part of the crucible where the vapor deposition material is disposed is exposed from the reflector, The cooling time is shortened. However, if the crucible heated to a high temperature is exposed from the reflector, it causes a malfunction of the vapor deposition apparatus due to distortion or melting of the constituent members of the vapor deposition apparatus arranged around the crucible due to thermal radiation from the crucible. In particular, when a vapor deposition material made of metal is used, the vapor deposition temperature (process temperature) is as high as, for example, 400 ° C. to 1000 ° C. or higher, so that the influence of thermal radiation from the crucible becomes large.

  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 as the workpiece. An evaporation source comprising a nozzle that emits toward the surface, and a step of placing the workpiece in a vacuum chamber. And (b) heating the vapor deposition material stored in the crucible by the heating unit to generate a vaporized vapor deposition material gas and forming a vapor deposition film on the object to be processed. And (c) after the step (b), supplying a gas into the crucible from the outside of the evaporation source through the nozzle, and stopping the heating unit to cool the crucible. It is a waste.

  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. Description of 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 gas supply in each process FIG. It is explanatory drawing which shows the temperature profile of the crucible in the cooling process which is the 1st and 2nd comparative example with respect to one Embodiment and embodiment of this invention. FIG. 7 is a cross-sectional view showing a state where an inert gas is supplied into the crucible shown in FIG. 4 in the cooling shown in FIG. 6. It is explanatory drawing which shows an example of the relationship between the temperature of the crucible shown in FIG. 4, and the saturated vapor pressure of vapor deposition material as a semi-logarithmic graph. It is explanatory drawing which shows the process flow of the vapor deposition method which is a modification with respect to FIG. 6, the temperature profile of the crucible in each process, ON-OFF of the heating part in each process, and the presence or absence of the gas supply in each process. FIG. 5 is a cross-sectional view illustrating an overall configuration of a film forming chamber which is a modification example of FIG. 4. It is sectional drawing which shows the modification of the film-forming chamber shown in FIG. It is sectional drawing which shows the modification of the gas supply part shown in FIG. It is an expanded sectional view of the nozzle periphery shown in FIG. It is sectional drawing which shows the layout of the gas supply part at the time of the vapor deposition process which forms a vapor deposition film in the vapor deposition method using the gas supply part shown in FIG. It is an expanded sectional view which shows the state which operated the gas supply part shown in FIG. 13 by rotational motion. It is an expanded sectional view which shows each state which operated further the gas supply part shown in FIG. It is sectional drawing which shows the structure of the evaporation source used for the cooling process which is a 2nd comparative example 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. The film formation chamber 102 is connected to the gas supply path GL introduced into the film formation chamber 102 from the outside of the film formation chamber 102 and the gas supply path GL, and an inert gas is supplied into the evaporation source 10. A gas supply unit 25 having a gas discharge port GN is arranged.

  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. In addition, a heat retaining portion (reflector) 15 that improves the heat retaining efficiency of the crucible 13 is disposed around the crucible 13.

  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 heat retaining part 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.

  Further, around the crucible 13 and the heating unit 14, a heat retaining unit 15 that improves the heat retaining efficiency of the crucible 13 is arranged. The heat retaining unit 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. That is, the heat retaining unit 15 has a function of reflecting the radiation from the crucible 13 and the heating unit 14 and improving the heat retaining efficiency of the crucible 13 disposed inside the heat retaining unit 15. In addition, since the heat retaining unit 15 reflects radiation from the crucible 13 and the heating unit 14, it serves as a protective member that suppresses the occurrence of distortion and melting due to radiant heat on the outer member (for example, the housing 11) of the heat retaining unit 15. It has the function of.

  A thermocouple TC is disposed in the evaporation source 10. The thermocouple TC is disposed, for example, between the crucible 13 and the heat retaining unit 15, and is fixed in a state where the temperature around the crucible 13 can be measured. The temperature signal detected by the thermocouple TC is transmitted to the outside of the film forming chamber 102, and the temperature of the crucible 13 and the temperature of the vapor deposition material 30 disposed in the crucible 13 can be grasped based on this temperature signal. it can.

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.

<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 the process flow of the vapor deposition method using the vapor deposition apparatus and the evaporation source shown in FIGS. 3 to 5, the temperature profile of the crucible in each process, the ON / OFF of the heating unit in each process, and the gas supply in each process It is explanatory drawing which shows the presence or absence. In the present application, for example, the temperature around the crucible 13 is measured by the thermocouple TC shown in FIGS. 4 and 5, and this is regarded as the temperature of the crucible 13. Therefore, for example, the temperature of the crucible shown in FIG. 6 is strictly the temperature of the thermocouple provided in the evaporation source 10, but in the following description, it will be described as the temperature of the crucible 13.

  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. At this time, the valve V2 of the gas supply unit 25 shown in FIG. 4 is closed, and no gas is supplied from the gas supply unit. 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 a vapor deposition film made of a metal material such as magnesium (Mg) is formed, the temperature T2 needs to be 500 ° C. or higher, so that the time required for the temperature raising process becomes long.

  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. In the maintenance process shown in FIG. 6, the deposition process is stopped and the above-described operation (maintenance operation) 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. In addition, after a maintenance process is complete | finished, as shown in FIG. 6, a vapor deposition preparation process is performed again and the preparation for forming a vapor deposition film on the new board | substrate 1 is performed. 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 and second comparative examples for the present embodiment and the present embodiment. 8 is a cross-sectional view showing a state where an inert gas is supplied into the crucible shown in FIG. 4 in the cooling shown in FIG. Moreover, FIG. 9 is explanatory drawing which shows an example of the relationship between the temperature of the crucible shown in FIG. 4, and the saturated vapor pressure of vapor deposition material as a semi-logarithmic graph.

  FIG. 18 is a cross-sectional view showing the structure of the evaporation source used in the cooling process as the second comparative example shown in FIG. The vapor deposition apparatus used in the first comparative example shown in FIG. 7 is the same as the present embodiment except that the gas supply unit 25 shown in FIG. 4 is not arranged. Will be described with reference to FIG.

  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, in the second comparative example, as shown in FIG. 18, 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. 18, 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. And in the cooling process which is a 2nd comparative example, the lower block 14b of the heating part 14 stops after the start of a cooling process, but the upper block 14a does not stop. That is, in the second comparative example, the heating of the upper block 14a is continued until the temperature of the vapor deposition material 30 reaches a temperature T3 (see FIG. 7) at which the vaporization of the vapor deposition material 30 stops. The crucible 13 and the vapor deposition material 30 are 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. According to the second comparative example, since the heating of the lid portion 13c is continued until the vaporization of the vapor deposition material 30 is stopped, 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 temperature that is the end point of the cooling process is low since the cooling rate is slow (for example, about 2 to 3 hours) from the temperature T2 to the temperature T3 (slow cooling period). For example, it takes about 5 to 10 hours to reach T1.

  As a third comparative example (not shown), during the cooling process, the heat retaining unit 15 shown in FIG. 5 is moved upward so that the periphery of the vapor deposition material 30 in the crucible 13 is exposed from the heat retaining unit 15. A configuration in which the periphery of the lid portion 13c is kept warm by the heat retaining portion 15 is also conceivable. However, since the heat retaining unit 15 has a function as a protective member that suppresses the occurrence of distortion and melting due to radiant heat in a member (for example, the casing 11) outside the heat retaining unit 15, this third comparative example. Then, the casing 11 and the like disposed around the crucible 13 are damaged by the heat radiation from the crucible 13, which causes a failure of the vapor deposition apparatus.

Based on the problems of the comparative examples described above, the inventor of the present application has studied the technique for suppressing the deposition of the vapor deposition material 30 and shortening the cooling time in the cooling process, and found the configuration of the present embodiment. The inventor of the present application pays attention to the relationship between the generation of the vapor deposition material gas 30a (see FIG. 4) and the saturated vapor pressure, and reduces the gasification of the vapor deposition material 30 by increasing the pressure in the crucible 13 in the cooling process. I found a configuration to stop or stop. That is, as shown in FIG. 8, in the cooling process, gas (inert gas) 26 is supplied from the gas supply unit 25 into the crucible 13 through the nozzle 12, and the pressure in the crucible 13 is adjusted to the saturated vapor of the vapor deposition material 30. By making it higher than the pressure, gasification of the vapor deposition material 30 can be reduced or stopped. As a method of supplying the gas 26, a method of supplying the gas 26 to the entire film forming chamber 102 which is a vacuum chamber is also conceivable. However, in this case, there is a concern that foreign matters remaining in the film formation chamber 102 are wound up by the gas 26 and mixed into the crucible 13. Therefore, it is preferable to selectively supply the gas 26 toward the crucible 13 and to locally increase the pressure in the crucible 13 from the viewpoint of preventing contamination. In the present embodiment, as shown in FIG. 8, the gas discharge port GN of the gas supply unit 25 is disposed in the film forming chamber 102 and is disposed toward the opening of the nozzle 12 of the evaporation source 10. Further, the gas supply path GL of the gas supply unit 25 is led out to the outside of the film forming chamber 102 and connected to a gas supply source TG arranged outside the film forming chamber 102. In the gas supply source TG, for example, an inert gas source such as argon (Ar) or nitrogen (N ₂ ) is stored. Further, between the gas supply source TG and the gas discharge port GN, a valve V2 for adjusting the presence / absence of gas supply and the flow rate is arranged and connected to the gas supply path GL. Accordingly, when the valve V2 is opened when the cooling process starts or after the start, the gas 26 is supplied from the outside of the evaporation source 10 to the inside of the crucible 13 through the nozzle 12. Further, since the gas discharge port GN of the gas supply unit 25 is disposed in the film forming chamber 102 and is disposed toward the opening of the nozzle 12 of the evaporation source 10, the gas 26 is selectively introduced into the crucible 13. The pressure in the crucible 13 can be locally increased. Further, the flow rate of the gas 26 and the supply pressure of the gas 26 can be adjusted by, for example, the opening degree of the valve V2.

  As shown in FIG. 9, the vapor pressure of the vapor deposition material 30 (see FIG. 8) is sufficiently smaller than the standard atmospheric pressure (about 101 kPa), and the pressure in the crucible 13 when starting the cooling process is, for example, Even when the crucible temperature is 1100 ° C., it is 100 Pa or less. For this reason, even if the pressure of the gas 26 to be supplied (see FIG. 8) is a value smaller than the standard atmospheric pressure, if the pressure is higher than the pressure in the crucible 13 in the vapor deposition step shown in FIG. The inside of 13 can be pressurized. Moreover, since the pressure in the crucible 13 becomes higher than the pressure in the space outside the crucible 13, a part of the gas 26 supplied into the crucible 13 is released from the nozzle 12 to the outside of the crucible 13, but the gas supply By continuously supplying the gas 26 from the portion 25 toward the nozzle 12, the pressure in the crucible 13 can be maintained in a state higher than the saturated vapor pressure of the vapor deposition material 30. That is, according to the present embodiment, in the cooling process, gas supply to the crucible 13 from the outside of the evaporation source 10 through the nozzle 12 is stopped or the vaporization of the vapor deposition material 30 is stopped or significantly reduced. Can do. For this reason, for example, as shown in FIG. 6, even when the heating unit 14 (see FIG. 8) is stopped at the start of the cooling process and the temperature of the crucible 13 rapidly decreases, the vapor deposition material 30 (FIG. 8). Precipitation) can be suppressed. Moreover, unlike the cooling curve P3 according to the second comparative example shown in FIG. 7, it is not necessary to provide a slow cooling period, so that the cooling time is greatly shortened (for example, less than half that of the second comparative example). )be able to. In addition, according to the present embodiment, in the cooling process, the cooling time can be shortened without moving the heat retaining unit 15, so that the member outside the heat retaining unit 15 (for example, the housing 11) Occurrence of melting can be suppressed.

  Further, if the gas 26 is supplied into the crucible 13 as in the present embodiment, the cooling time can be further shortened compared to the first comparative example shown in FIG. The gas 26 supplied into the crucible 13 comes into contact with the wall surface within the crucible 13 and the vapor deposition material 30 and heat exchange is performed. The gas 26 whose temperature has been increased by heat exchange moves upward of the crucible 13, and a part of the gas 26 is discharged from the nozzle 12 to the outside of the crucible 13. On the other hand, the gas 26 newly supplied from the gas discharge port GN of the gas supply unit 25 has a lower temperature than the gas 26 discharged from the nozzle, and therefore easily enters the crucible 13. As described above, the gas 26 whose temperature has been increased by heat exchange is released to the outside, and the gas 26 having a relatively low temperature is supplied to the inside, so that the heat exchange proceeds and the temperature decrease of the crucible 13 can be promoted. it can. For this reason, as shown in FIG. 7, the cooling curve P1 in the cooling process of this Embodiment can shorten cooling time compared with the cooling curve P2 at the time of carrying out natural cooling. For example, in the example of the cooling curve P1 shown in FIG. 7, the time (cooling time) for the temperature of the crucible 13 to drop from the temperature T2 to the temperature T1 is about 2.5 hours to 5 hours.

<Preferred embodiment>
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 an explanatory diagram showing a process flow of a vapor deposition method which is a modification to FIG. 6, a temperature profile of the crucible in each process, ON / OFF of a heating unit in each process, and presence / absence of gas supply in each process. FIG. 11 is a cross-sectional view showing the overall configuration of the film forming chamber, which is a modification of FIG. FIG. 12 is a cross-sectional view showing a modification of the film forming chamber shown in FIG.

First, the gas 26 shown in FIG. 8 is preferably an inert gas from the viewpoint of suppressing generation of impurities by reacting with the vapor deposition material 30 disposed in the crucible 13 and the crucible 13 itself. Here, the inert gas generates impurities in the vapor deposition material 30 disposed in the crucible 13 or in the crucible 13 itself rather than air that is an atmospheric gas outside the film forming chamber 102 that is a vacuum chamber. This means that it is a difficult gas and includes so-called noble gases, nitrogen and the like. Further, the preferred gas type varies depending on the constituent material of the crucible 13 and the process temperature (temperature T2 shown in FIG. 6). For example, when the temperature T2 exceeds 800 ° C. and the crucible 13 is formed of a metal material such as molybdenum (Mo), tantalum (Ta), tungsten (W), impurities are generated. Since it is easy, it is preferable that the gas 26 is argon (Ar) gas. On the other hand, when the crucible 13 is made of ceramic such as alumina or boron nitride, or carbon (c), nitrogen (N ₂₎ is cheaper than argon gas unless it reacts with the vapor deposition material 30 to generate impurities. ) Gas is preferred. In the case where a vapor deposition film made of an organic material is formed at a temperature T2 lower than 400 ° C., nitrogen gas or carbon dioxide (CO ₂ ) gas can be used.

  From the viewpoint of shortening the cooling time, it is preferable to continuously supply the gas 26 until the temperature of the crucible 13 reaches the temperature T1, as shown in FIG. When the supply of the gas 26 is stopped in the middle of the cooling process and the temperature T1 is reached by natural cooling, the cooling rate decreases when the ambient temperature and the temperature of the crucible 13 become close to each other. However, by continuously supplying the gas 26, heat exchange by the gas 26 is continued even when the atmospheric temperature and the temperature of the crucible 13 are close to each other, so that the cooling time can be further shortened as compared with the case of natural cooling. However, from the viewpoint of reducing the cost of the gas 26 used in the cooling process, it is preferable to switch the gas 26 during the cooling process. For example, as described above, when the temperature T2 exceeds 800 ° C. and the crucible 13 is formed of a metal material such as molybdenum, tantalum, or tungsten, the gas 26 is used at the start of the cooling process. Argon gas is supplied. And when the temperature of the crucible 13 becomes 400 degrees C or less, for example, the kind of gas 26 is switched, for example, it is set as nitrogen gas and carbon dioxide gas cheaper than argon gas. In this case, the cooling time can be shortened and the manufacturing cost for forming the vapor deposition film can be reduced.

  On the other hand, from the viewpoint of reducing the amount of gas 26 used, as in the modification shown in FIG. 10, the supply of the gas 26 is stopped in the middle of the cooling process, and thereafter the temperature of the crucible 13 reaches the temperature T1 by natural cooling. It is preferable to make it. In this case, it is preferable to stop the supply of the gas 26 when the temperature of the crucible 13 is lowered to a temperature at which the amount of the vapor deposition material 30 to be gasified is sufficiently small even if the supply of the gas 26 is stopped. As an embodiment for performing the vapor deposition method as shown in FIG. 10, for example, as shown in FIG. 11, the temperature of the sensor 27 for measuring the vapor deposition material gas 30 a and the temperature of the crucible 13 is measured in the film forming chamber 102. A temperature sensor (not shown) is provided in advance. In the vapor deposition preparation step shown in FIG. 10, the temperature (gasification temperature) of the crucible 13 when the sensor 27 detects the vapor deposition material gas 30a is recorded in the sensor 27 and the controller 28 electrically connected to the temperature sensor. To do. In the cooling process, the temperature of the crucible 13 is measured, and when the temperature is lowered to the gasification temperature or lower, for example, the control unit 28 closes the valve V2 to stop the supply of the gas 26. As another embodiment, in the vapor deposition step and the cooling step shown in FIG. 10, the detection rate of the vapor deposition material gas 30a (detected amount within the set measurement range) is continuously detected by the sensor 27 (see FIG. 11). measure. When the detection rate of the vapor deposition material gas 30a detected in the cooling step is equal to or less than a preset reference value (for example, 1/10 to 1/100 or less of the detection rate in the vapor deposition step), the valve V2 is turned on. The supply of the gas 26 is stopped by closing. Thus, if the supply of the gas 26 is stopped in the middle of the cooling process, the cooling time becomes longer than that in the example shown in FIG. 6, but the amount of the gas 26 used can be reduced.

  In the cooling process of the present embodiment, the supply of the gas 26 from the gas supply unit 25 is started and the heating unit 14 is stopped to cool the crucible 13 and the vapor deposition material 30 in the crucible 13. It is preferable to stop the heating unit 14 after the supply of 26 is started. As shown in FIG. 9, since the vapor deposition material 30 has a very low saturated vapor pressure, if the supply of the gas 26 is started, the amount of the vapor deposition material 30 that is vaporized in a short time is greatly reduced. However, from the viewpoint of more reliably suppressing the deposition material 30 from depositing on the wall surface in the crucible 13 or the inner side surface of the lid portion 13 c, the timing for stopping the heating unit 14 is after the supply of the gas 26 is started. It is preferable to carry out with. Moreover, the timing which stops the heating part 14 can be determined by the elapsed time after starting supply of the gas 26, for example. Further, as a method of more reliably suppressing the deposition of the vapor deposition material 30, after confirming that the detected amount of the vapor deposition material gas 30a is sufficiently small using the sensor 27 shown in FIG. A method of stopping the unit 14 is effective.

  As shown in FIG. 4, in the vapor deposition step, it is necessary to arrange the gas supply unit 25 so as to avoid a path (discharge path) through which the vapor deposition material gas 30 a is discharged from the nozzle 12 toward the substrate 1. For this reason, as shown in FIG. 4, the gas discharge port GN of the gas supply unit 25 is arranged away from the nozzle 12 and the axis (virtual line) of the discharge path of the vapor deposition material gas 30 a from the nozzle 12 to the substrate 1. It is preferable that the discharge angle from the gas discharge port GN be inclined with respect to AL. Thereby, the vapor deposition film can be stably formed on the substrate 1 without performing the operation of retracting the gas discharge port GN during the vapor deposition process. In other words, in the mode shown in FIG. 4, the supply of the gas 26 (see FIG. 8) can be started without moving the position of the gas discharge port GN when shifting from the vapor deposition process to the cooling process. Further, since it is not necessary to move the position of the gas discharge port GN when shifting from the vapor deposition process to the cooling process, the relationship between the position of the nozzle 12 and the gas discharge port GN and the discharge angle of the gas 26 is adjusted with high accuracy. can do. As a result, the gas 26 can be reliably discharged toward the nozzle 12 in the cooling step. Thus, in the present embodiment, it is not necessary to move the position of the gas discharge port GN when shifting from the vapor deposition process to the cooling process, and therefore, the gas supply path GL is configured by, for example, a metal pipe.

  Further, the valve V1 connected to the exhaust path VL is preferably closed in the cooling process. If the cooling process is performed with the valve V1 closed, the gas 26 can be convected in the film formation chamber 102 shown in FIG. 8 because the exhaust in the film formation chamber 102 can be stopped in the cooling process. . For this reason, cooling of the crucible 13 can be promoted, and the cooling time can be further shortened. Further, as a mode for further promoting the convection of the gas in the film forming chamber 102 in the cooling step, the purge gas 31 is supplied into the film forming chamber 102 separately from the gas supply unit 25 as in the modification shown in FIG. The purge gas supply unit 32 to be arranged can be arranged. According to the configuration shown in FIG. 12, the supply amount of the purge gas 31 supplied from the purge gas supply source TP is controlled independently of the gas 26 supplied from the gas supply unit 25 by adjusting the opening degree of the valve V3. Therefore, the purge gas 31 can be efficiently convected in the film formation chamber 102. As with the gas 26, the purge gas 31 is preferably an inert gas from the viewpoint of suppressing the generation of impurities, and is particularly preferably the same gas as the gas 26.

<Other variations>
Next, modifications other than the above-described modification will be described. 13 is a cross-sectional view showing a modification of the gas supply unit shown in FIG. 8, and FIG. 14 is an enlarged cross-sectional view around the nozzle shown in FIG. FIG. 15 is a cross-sectional view showing the layout of the gas supply unit during the vapor deposition process for forming a vapor deposition film in the vapor deposition method using the gas supply unit shown in FIG. FIGS. 16 and 17 are enlarged cross-sectional views showing states in which the gas supply unit shown in FIGS. 13 to 15 is operated.

  The gas supply unit 25 shown in FIG. 8 is different from the gas supply unit 35 shown in FIGS. 13 to 17 in the following points. First, the gas supply part 35 shown in FIGS. 13-18 is connected to the plug part (nozzle cap) NC which the gas supply path GL covers the opening part of the nozzle 12 in a cooling process. The plug portion NC is formed with a through hole that constitutes a part of the gas supply path GL. As shown in FIG. 14, the tip of the through hole has a gas discharge port GN that discharges the gas 26 into the crucible 13. It has become.

  In the vapor deposition method using the gas supply unit 35, the opening of the nozzle 12 is covered with the plug NC of the gas supply unit 35 as shown in FIG. At this time, the gas discharge port GN (see FIG. 14) of the gas supply unit 35 is disposed inside the nozzle 12 or the crucible 13. If the valve V2 shown in FIG. 3 is opened in this state, the gas 26 can be supplied into the crucible 13 more reliably than the gas supply unit 25 shown in FIG. When the opening of the nozzle 12 is covered with the plug NC of the gas supply unit 35, the nozzle 12 and the plug NC can be brought into close contact with each other to completely close the opening of the nozzle 12. However, as shown in FIG. 14, it is more preferable to provide a gap without closely contacting the nozzle 12 and the plug portion NC. As described above, in the cooling step, the gas 26 whose temperature has been increased by heat exchange in the crucible 13 gathers upward. Therefore, by providing a gap between the nozzle 12 and the plug NC, the gas 26 whose temperature has risen can be discharged from the gap to the outside of the evaporation source 10, so that the gas 26 having a relatively low temperature is supplied to the inside. As a result, heat exchange proceeds and the temperature drop of the crucible 13 can be promoted. FIG. 14 shows an example in which the gas discharge port GN of the gas supply unit 35 is disposed inside the nozzle 12. However, if the gas discharge port GN is disposed on the opening of the nozzle 12, it is ensured. Since the gas 26 can be supplied to the crucible 13, the gas discharge port GN may be disposed outside the nozzle 12. However, if the distance between the gas discharge port GN and the opening of the nozzle 12 increases, a part of the gas 26 may diffuse to the outside of the nozzle 12, so the gas discharge port GN is arranged near the opening of the nozzle 12. It is particularly preferable to arrange in the opening of the nozzle 12 or in the crucible 13.

  Moreover, in this modification, since the plug part NC is disposed on the nozzle 12 which is the discharge port of the vapor deposition material gas 30a (see FIG. 15) after the start of the cooling process, the vapor deposition material 30 (see FIG. 13) may precipitate. Thus, even when the vapor deposition material 30 is deposited on the surface of the plug portion NC, by providing a gap between the nozzle 12 and the plug portion NC, the plug portion NC and the nozzle 12 are bonded by the deposit. This can be suppressed. Further, from the viewpoint of more reliably suppressing the deposition material 30 from depositing on the surface of the plug part NC, as shown in FIG. 14, a heating part 36 may be provided in the plug part NC to heat the plug part NC. preferable.

  By the way, as shown in FIG. 13, the plug NC of the gas supply unit 35 is disposed so as to cover the nozzle 12 in the cooling process. Therefore, in the vapor deposition process shown in FIG. 6, for example, as shown in FIG. Needs to be moved from above the nozzle 12. Therefore, in the modification shown in FIGS. 13 to 17, it is possible to move the position of the plug portion NC at the time of transition from the vapor deposition process to the cooling process shown in FIG. 6 and at the time of transition from the cooling process to the maintenance process. I support it. For example, in the example shown in FIGS. 13 to 17, the plug portion NC is fixed to the support portion SB that supports the plug portion NC and the gas supply path GL connected to the plug portion NC. The method for fixing the stopper NC is not particularly limited. For example, the stopper NC and the support SB may be integrally formed. The support part SB is movable in a state where the plug part NC is fixed (supported state). For example, when shifting from the vapor deposition process to the cooling process, the support part SB moves as shown in FIGS. 16 and 17. . First, as shown in FIG. 16, it operates by rotational movement so that the plug portion NC is positioned on the nozzle 12 with a part of the support portion SB as a fulcrum. Next, as shown in FIG. 17, the entire support portion SB moves downward together with the plug portion NC, and covers the opening of the nozzle 12 with the plug portion NC as shown in FIG. In this state, the valve V2 shown in FIG. 13 is opened, and the supply of the gas 26 is started. Further, when the cooling process shown in FIG. 6 is shifted to the maintenance process, the reverse operation of the operation shown in FIGS. 17 and 16 is performed. Further, since the gas supply path GL is connected to the plug part NC that moves when the process is shifted, at least a part of the gas supply path GL is configured by a pipe that can be deformed according to the movement of the plug part NC. .

  Note that the modified example is the same as the embodiment shown in FIGS. 1 to 9 except for the differences described above, and thus redundant description is omitted. Also, the various modifications described above can be applied in combination with the modifications shown in FIGS.

  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.

  In the above-described embodiment, the mode of releasing the vapor deposition material gas 30a from the fixed evaporation source 10 has been described as the mode of the evaporation source. However, as a modification, the evaporation source 10 and the substrate 1 are relatively moved. The present invention can be applied to an embodiment in which a deposited film is formed on the substrate 1. As described above, the method of forming the vapor deposition film while relatively moving the evaporation source 10 and the substrate 1 is effective even when the area of the vapor deposition film formation surface of the substrate 1 as the object to be processed is large. This is advantageous in that the film thickness and film quality can be made uniform. Further, in the vapor deposition method using the vapor deposition apparatus that relatively moves the evaporation source and the substrate, as shown in FIG. 4, with respect to the axis (virtual line) AL of the discharge path of the vapor deposition material gas 30a from the nozzle 12 to the substrate 1 Thus, it is not necessary to arrange the discharge angle from the gas discharge port GN to be inclined. In this case, although not shown in the figure, when starting the cooling process or before that, the evaporation source is moved or the gas discharge port of the gas supply unit is moved relative to the gas supply unit gas. The discharge port is arranged at a position where the opening of the evaporation source nozzle faces. Thereafter, if gas is selectively supplied from the gas supply unit toward the crucible, the pressure in the crucible can be locally increased.

  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 transport layer 4b Light emitting layer 4c Electron transport layer 10, 10A Evaporation source 11 Housing 11a Surface 11c Lid 11d Main body 11e Opening Part 12 nozzle 13 crucible 13c lid part 13d body part 13e opening 14 heating part 14a upper block 14b lower block 15 heat retaining part (reflector)
21 substrate holding part 22 mask 22a opening part 25, 35 gas supply part 26 gas 27 sensor 28 control part 30 vapor deposition material 30a vapor deposition material gas 31 purge gas 32 purge gas supply part 36 heating part 100 vapor deposition apparatus 101 delivery chamber 101a loader part 101b unloader part 102 Deposition chamber 103 Transfer chamber 103a Robot (substrate transfer device)
GL Gas supply path GN Gas outlet NC Plug part P1, P2, P3 Cooling curve SB Support part T1, T2, T3 Temperature TC Thermocouple TG Gas supply source TP Purge gas supply source V1, V2, V3 Valve VL Exhaust path VP Vacuum pump

Claims (15)

(A) preparing an evaporation source including a crucible for storing a vapor deposition material, a heating unit for heating the crucible, and a nozzle for discharging the vapor deposition material gasified in the crucible toward an object to be processed;
(B) heating the vapor deposition material stored in the crucible by the heating unit to generate a vaporized vapor deposition material gas, and forming a vapor deposition film on the object to be processed;
(C) After the step (b), gas is selectively supplied from the gas supply unit disposed outside the evaporation source to the inside of the crucible through the nozzle to locally reduce the pressure inside the crucible. And cooling the crucible by stopping the heating unit,
The vapor deposition method characterized by including. The vapor deposition method according to claim 1,
The vapor deposition method characterized in that the gas supplied into the crucible in the step (c) is an inert gas. In the vapor deposition method of Claim 1 or Claim 2,
In the step (c), by the time the cooling of the crucible is started, the position of the gas discharge port of the evaporation source or the gas supply unit is relatively moved, and the gas discharge port of the gas supply unit and A vapor deposition method, wherein gas is selectively supplied from the gas supply unit toward the inside of the crucible through the nozzle while facing the opening of the nozzle. In the vapor deposition method of Claim 1 or Claim 2,
A gas discharge port of the gas supply unit for supplying the gas into the crucible in the step (c) is disposed apart from the nozzle;
The vapor deposition method, wherein the gas discharge angle from the gas discharge port is inclined with respect to an axis of the vapor deposition material gas discharge path from the nozzle to the object to be processed. In the vapor deposition method of Claim 1 or Claim 2,
The gas supply unit that supplies the gas into the crucible in the step (c) includes a plug portion that covers the opening of the nozzle in the step (c),
A gas supply path of the gas supply unit is connected to a through hole formed in the plug unit, and a gas discharge port of the gas supply unit is formed on the opening of the nozzle in the step (c). The vapor deposition method characterized by being arranged in the opening or in the crucible. In the vapor deposition method of Claim 5,
In the step (c), the vapor deposition method is characterized in that the plug portion is heated. In the vapor deposition method in any one of Claims 1-6,
In the step (c), the gas is continuously supplied until the temperature of the crucible reaches a temperature that becomes the end point of the cooling. In the vapor deposition method of Claim 7,
In the step (c), the vapor deposition method is characterized in that the type of the gas is switched and supplied during the cooling. In the vapor deposition method in any one of Claims 1-6,
In the step (c), the gas supply is stopped before the temperature of the crucible reaches a temperature at which the end point of the cooling is reached. The vapor deposition method according to claim 9.
A vapor deposition method, wherein a timing for stopping the supply of the gas is detected by a sensor. A vacuum chamber, an evaporation source disposed in the vacuum chamber, a gas supply unit that supplies gas into the evaporation source, and a holding unit that holds 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, and a nozzle for discharging the vapor deposition material gas vaporized in the crucible toward the object to be processed,
The gas supply unit
A gas supply path that is introduced into the vacuum chamber from the outside of the vacuum chamber, and a gas discharge port that is connected to the gas supply path and supplies the gas into the crucible from the nozzle of the evaporation source. The vapor deposition apparatus characterized by the above-mentioned. The evaporator according to claim 11.
The gas supply unit is connected to an inert gas supply source, and the inert gas is discharged from the gas discharge port. The vapor deposition apparatus according to claim 11 or 12,
The gas discharge port of the gas supply unit is disposed apart from the nozzle,
The vapor deposition apparatus, wherein the gas discharge angle from the gas discharge port is inclined with respect to an axis of the vapor deposition material gas discharge path from the nozzle to the object to be processed. The vapor deposition apparatus according to claim 11 or 12,
The gas supply unit includes a plug that covers the opening of the nozzle,
The stopper is fixed to a support that moves the stopper from the opening of the nozzle,
The gas supply path is connected to a through hole formed in the plug portion,
When the plug portion is disposed at a position covering the nozzle opening, the gas discharge port of the gas supply unit is disposed on the opening of the nozzle, in the opening of the nozzle or in the crucible. The vapor deposition apparatus characterized by the above-mentioned. The vapor deposition apparatus according to claim 14, wherein
The vapor deposition apparatus, wherein the plug part is provided with a heating part for heating the plug part.

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