JP7299028B2 - Film forming apparatus and film forming method by magnetron sputtering - Google Patents

Description

The present invention relates to a film forming apparatus and film forming method using a magnetron sputtering method, and more particularly to a film forming apparatus and film forming method for forming a sealing film for sealing electronic elements provided on a substrate.

This type of film forming apparatus and film forming method is used, for example, to form a sealing film for sealing an organic electroluminescence (hereinafter referred to as "EL") element as an electronic element. However, although the magnetron sputtering method has a relatively simple structure, it has the advantage of being able to form a sealing film at a relatively high speed. It has the drawback of being stowed away. Conventionally, for example, a technique disclosed in Japanese Patent Laid-Open No. 2002-200002 is known to compensate for the drawback of the magnetron sputtering method.

According to the technique disclosed in this patent document 1, first, the sealing film of the first layer is formed by the ion beam sputtering method. In the ion beam sputtering method, since no plasma is generated in the vacuum chamber containing the substrate, the organic EL element on the substrate is not affected by the plasma. In addition, according to the technique disclosed in Patent Document 1, the second and subsequent sealing films are formed by a film formation method other than the ion beam sputtering method. A magnetron sputtering method is mentioned as one of film forming methods other than the ion beam sputtering method referred to here.

Further, in another patent document 2, a first layer sealing film is formed by a facing target type sputtering method that is relatively less affected by plasma, and then a film formation method other than the facing target type sputtering method is described. A technique is disclosed in which the second and subsequent layers of the sealing film are formed by A magnetron sputtering method is mentioned as one of film forming methods other than the facing target type sputtering method referred to here.

JP 2009-37811 A JP-A-2009-37813

However, the technique disclosed in the above-mentioned Patent Document 1 requires a configuration for realizing the ion beam sputtering method and a configuration for realizing a film formation method other than the ion beam sputtering method. The configuration of the entire device becomes large and complicated. Moreover, the configuration for realizing the ion beam sputtering method is larger and more complicated than the configuration for realizing the magnetron sputtering method, for example, so that the configuration of the entire apparatus becomes significantly larger and more complicated.

Similarly, the technique disclosed in Patent Document 2 also requires a configuration for realizing the facing target type sputtering method and a configuration for realizing a film forming method other than the facing target type sputtering method. As a result, the configuration of the entire device becomes large and complicated. Moreover, the structure for realizing the facing target type sputtering method is also larger and more complicated than the structure for realizing the magnetron sputtering method, so that the structure of the entire apparatus becomes significantly larger and more complicated. .

Therefore, it would be extremely convenient if, for example, a technique was created that could form a sealing film that seals an electronic element such as an organic EL element by magnetron sputtering while suppressing damage to the electronic element.

Therefore, the present invention provides a novel film forming apparatus and a film forming method that can form a sealing film that seals electronic elements such as organic EL elements while suppressing damage to the electronic elements by a magnetron sputtering method. The purpose is to provide a method.

In order to achieve this object, the present invention includes a first invention relating to a film forming apparatus using a magnetron sputtering method and a second invention relating to a film forming apparatus particularly suitable for mass production. In addition, the present invention includes a third invention relating to a film forming method by magnetron sputtering and a fourth invention relating to a film forming method suitable for mass production.

A first aspect of the present invention is a film forming apparatus for forming a sealing film for sealing an electronic element provided on a substrate by magnetron sputtering, comprising a vacuum chamber in which the substrate is accommodated. . Furthermore, the first invention comprises a magnetron cathode, a discharge gas introduction means, a sputtering power supply means, a reactive gas introduction means, a filament, a discharge power supply means, and a control means. A magnetron cathode has a target, which is the material of the sealing membrane. This magnetron cathode is provided in a vacuum chamber so that the surface of the target to be sputtered faces the electronic elements on the substrate. The discharge gas introducing means introduces a discharge gas into the vacuum chamber. The sputtering power supply means uses the vacuum chamber as an anode and the magnetron cathode as a cathode, and supplies sputtering power to both of them. As a result, the discharge gas is discharged to generate plasma in the vacuum chamber. The reactive gas introducing means introduces a reactive gas, which is another material of the sealing film, into the vacuum chamber. A filament is provided between the substrate and the sputtered surface of the target. The filament is heated by being supplied with thermionic emission power and emits thermionic electrons. The discharge power supply means uses the vacuum chamber as an anode and the filament as a cathode, and supplies discharge power to both of them. This accelerates the thermoelectrons and induces an arc discharge around the filament. Then, the control means controls at least the reactive gas introduction means so that a laminated film in which a plurality of films of different types are laminated is formed as a sealing film. In addition, the sputtering current, which is the current component of the sputtering power, is set to 1.5 A or more and 8 A or less.

In the first aspect of the invention, the control means is configured to form a laminated film in which a film containing a component of the reactive gas and a film not containing the component of the reactive gas are laminated as the sealing film. In addition, introduction of the reactive gas into the vacuum chamber by the reactive gas introducing means may be turned on/off.

The electronic device referred to here includes, for example, an organic EL device.

The target may also be made of aluminum (Al), for example. And the reactive gas may include nitrogen (N ₂ ) gas. In this case, a laminated film in which a reaction film containing nitrogen and aluminum as components and a monoelement film of aluminum are laminated is formed as a sealing film.

A second aspect of the present invention is a film forming apparatus for forming a sealing film for sealing electronic elements provided on a substrate by magnetron sputtering, and is suitable for mass production as described above. . Specifically, the second invention comprises a vacuum chamber and a storage means. The vacuum chamber has a plurality of film forming chambers for individually forming a plurality of films of different types that constitute the sealing film. The accommodation unit sequentially accommodates the substrates in each film forming chamber of the vacuum chamber so that a laminated film in which a plurality of films are laminated is formed as a sealing film. Further, each film forming chamber is provided with a magnetron cathode, a discharge gas introduction means, a sputtering power supply means, a filament, and a discharge power supply means. A magnetron cathode has a target, which is the material of the sealing membrane. This magnetron cathode is provided in the deposition chamber so that the surface of the target to be sputtered faces the electronic elements on the substrate. The discharge gas introducing means introduces the discharge gas into the film forming chamber. The sputtering power supply means uses the film forming chamber as an anode and the magnetron cathode as a cathode, and supplies sputtering power to both of them. As a result, the discharge gas is discharged to generate plasma in the deposition chamber. A filament is provided between the substrate and the surface to be sputtered. The filament is heated by being supplied with thermionic emission power and emits thermionic electrons. The discharge power supply means uses the film formation chamber as an anode and the filament as a cathode, and supplies discharge power to both of them. This accelerates the thermoelectrons and induces an arc discharge around the filament. In addition, some of the film formation chambers are equipped with reactive gas introduction means. This reactive gas introducing means introduces a reactive gas, which is another material of the sealing film, into the film forming chamber. In addition, the sputtering current, which is the current component of the sputtering power, is set to 1.5 A or more and 8 A or less.

In the second invention, each film forming chamber of the vacuum chamber may be provided so as to be continuous with each other. In this case, the storage means may include transport means for transporting the substrates so that the substrates pass through the respective film formation chambers sequentially. This configuration is used, for example, for realization of an in-line film forming apparatus.

Additionally, in this configuration, the substrate may be elongated. In this case, it is desirable that the transport means transport the long substrate along the longitudinal direction of the substrate. Such a configuration is used, for example, to realize a winding-type film forming apparatus (so-called roll coater).

A third aspect of the present invention is a film formation method for forming a sealing film for sealing an electronic element provided on a substrate by magnetron sputtering, wherein a discharge gas is introduced into a vacuum chamber. It includes a discharge gas introduction step. Here, in the vacuum chamber, the sputtered surface of the target of the magnetron cathode, which is the material of the sealing film, faces the electronic elements on the substrate. Moreover, the third invention includes a sputtering power supply step, a reactive gas introduction step, a thermoelectron emission step, a discharge power supply step, and a control step. In the sputtering power supply step, sputtering power is supplied to both the vacuum chamber as the anode and the magnetron cathode as the cathode. As a result, the discharge gas is discharged to generate plasma in the vacuum chamber. In the reactive gas introduction step, a reactive gas, which is another material of the sealing film, is introduced into the vacuum chamber. In the thermionic emission step, power for thermionic emission is supplied to the filament. A filament is provided between the substrate and the sputtered surface of the target. By supplying the thermionic emission power to the filament, the filament is heated and thermionic electrons are emitted from the filament. In the discharge power supply step, the vacuum chamber is used as an anode and the filament is used as a cathode, and discharge power is supplied to both of them. This accelerates the thermoelectrons and induces an arc discharge around the filament. Then, in the controlling step, at least the mode of introducing the reactive gas in the reactive gas introducing step is controlled so that a laminated film in which a plurality of films of different types are laminated is formed as the sealing film. In addition, the sputtering current, which is the current component of the sputtering power, is set to 1.5 A or more and 8 A or less.

A fourth aspect of the present invention is a film formation method for forming a sealing film for sealing an electronic element provided on a substrate by magnetron sputtering, which is suitable for mass production as described above. Specifically, the fourth invention includes a containing step. In this accommodation step, a vacuum chamber having a plurality of film formation chambers for individually forming a plurality of films is formed so that a plurality of films of different types are laminated as a sealing film. The substrates are sequentially accommodated in the plurality of film formation chambers. In addition, a discharge gas introduction step, a sputtering power supply step, a thermoelectron emission step, and a discharge power supply step are performed for each film forming chamber. In the discharge gas introducing step, the discharge gas is introduced into the film forming chamber. Here, in the film formation chamber, the target to be sputtered of the magnetron cathode having the target, which is the material of the sealing film, faces the electronic element on the substrate. Then, in the sputtering power supply step, sputtering power is supplied to both the film formation chamber as the anode and the magnetron cathode as the cathode. As a result, the discharge gas is discharged to generate plasma in the deposition chamber. In the thermionic emission step, power for thermionic emission is supplied to the filament. A filament is provided between the substrate and the sputtered surface of the target. By supplying the thermionic emission power to the filament, the filament is heated and thermionic electrons are emitted from the filament. Then, in the discharge power supply step, discharge power is supplied to both the film forming chamber as the anode and the filament as the cathode. This accelerates the thermoelectrons and induces an arc discharge around the filament. Further, in some of the film formation chambers, a reactive gas introduction step is performed to introduce a reactive gas, which is another material of the sealing film, into the film formation chambers. In addition, the sputtering current, which is the current component of the sputtering power, is set to 1.5 A or more and 8 A or less.

According to the present invention, it is possible to form a sealing film that seals an electronic element such as an organic EL element while suppressing damage to the electronic element by the magnetron sputtering method. Moreover, since the magnetron sputtering method is used, the sealing film can be formed at a relatively high speed.

FIG. 1 is a diagram showing a schematic configuration of a magnetron sputtering apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram schematically showing the configuration of the object to be processed in the first embodiment. FIG. 3 is a diagram schematically showing the configuration of the sealing film in the first embodiment. FIG. 4 is a captured image of the filament and its surroundings in the first embodiment. FIG. 5 is a graph showing the relationship between discharge power, sputtering current, and sputtering voltage in the first embodiment. FIG. 6 is a list showing film formation conditions during the experiment for the first embodiment. FIG. 7 is a diagram showing the experimental results for the first example side by side with the experimental results for each of the two comparative examples. FIG. 8 is a diagram showing a schematic configuration of a mass-produced magnetron sputtering apparatus according to a second embodiment of the present invention. FIG. 9 is a diagram showing a schematic configuration of a winding-type magnetron sputtering apparatus according to a third embodiment of the present invention.

[First embodiment]
A first embodiment of the present invention will be described with reference to FIGS. 1 to 7. FIG.

As shown in FIG. 1, a magnetron sputtering apparatus 10 according to the first embodiment includes a substantially cylindrical vacuum chamber 12 . The vacuum chamber 12 is installed with the two ends of the substantially cylindrical shape facing up and down, that is, with the central axis of the substantially cylindrical shape extending in the vertical direction. Also, the portions corresponding to both ends of the substantially cylindrical shape are closed as the upper and lower surfaces of the vacuum chamber 12 . The vacuum chamber 12 is made of metal having relatively high mechanical strength, corrosion resistance and heat resistance, such as stainless steel such as SUS304, and its wall portion (casing) is grounded. The diameter (inner diameter) inside the vacuum chamber 12 is, for example, about 1000 mm, and the height dimension inside the vacuum chamber 12 is, for example, about 800 mm. The shape and dimensions of the vacuum chamber 12 are merely examples, and are appropriately determined according to various conditions such as the dimensions and the number of objects to be processed 100, which will be described later.

An exhaust port 12a is provided at an appropriate position on the wall of the vacuum chamber 12, for example, at an appropriate position on the wall forming the side surface of the vacuum chamber 12 (the left position in FIG. 1). Although not shown, the exhaust port 12a is connected to a vacuum pump as an exhaust means outside the vacuum chamber 12 via an exhaust pipe. As the vacuum pump, particularly as the main exhaust pump, for example, a turbo-molecular pump is employed, but not limited to this. In addition, a pressure control device as pressure control means for controlling the pressure in the vacuum chamber 12 is provided in the middle of the exhaust pipe. Note that the vacuum pump also functions as pressure control means.

Focusing on the interior of the vacuum chamber 12 , a magnetron cathode 14 is arranged substantially in the center of the lower portion within the vacuum chamber 12 . The magnetron cathode 14 has a target 142 which is a material of a sealing film 200 to be described later, and a magnet unit 144 provided on the back side (lower side in FIG. 1) which is one main surface of the target 142 .

The target 142 is made of, for example, substantially disk-shaped high-purity (preferably 99.999% or higher) aluminum. The target 142 has a diameter of, for example, 300 mm (about 12 inches) and a thickness dimension of, for example, 8 mm. The shape and dimensions of this target 142 are also just an example, and are appropriately determined according to various situations such as the dimensions and the number of objects to be processed 100, which will be described later.

The magnet unit 144 is provided behind the target 142 as described above. This magnet unit 144 holds the target 142 firmly. In addition, the magnet unit 144 incorporates a permanent magnet as a magnetic field (magnetic field) forming means (not shown), and is arranged near the surface to be sputtered, which is the other main surface of the target 142 (upper surface in FIG. 1). Creates a magnetic field in space. The magnet unit 144 is fixed, for example, to the wall forming the lower surface of the vacuum chamber 12 with the surface of the target 142 to be sputtered facing upward. The magnet unit 144 is also provided with a water cooling mechanism (not shown) serving as cathode cooling means for cooling the entire magnetron cathode 14 including the magnet unit 144 .

Such a magnetron cathode 14 is covered with the ground shield 16 except for the surface of the target 142 to be sputtered, in other words, with the surface to be sputtered exposed. The earth shield 16 is made of a metal having high mechanical strength, corrosion resistance and heat resistance, such as stainless steel such as SUS304. The ground shield 16 is electrically insulated from the magnetron cathode 14 and electrically connected to the vacuum chamber 12 .

Furthermore, the magnetron cathode 14 is connected outside the vacuum chamber 12 to a sputtering power supply 18 as a sputtering power supply means. The sputtering power supply 18 uses the vacuum chamber 12 (wall portion) as an anode and the magnetron cathode 14 as a cathode, and supplies DC sputtering power Es to both of them. The capacity of this sputtering power supply 18 is, for example, 10 kW (=1000 V×10 A) at maximum. The sputtering power supply 18 also has three operating modes: constant power mode, constant voltage mode, and constant current mode. The constant power mode is a mode in which the power value of the sputtering power Es is kept constant. The constant voltage mode is a mode in which the sputtering voltage (also called target voltage) Vs, which is the voltage component of the sputtering power Es, is kept constant. The constant current mode is a mode in which the sputtering current (also called target current) Is, which is the current component of the sputtering power Es, is kept constant. Here, the sputter power supply 18 is set to operate in constant power mode.

A filament 20 as a hot cathode is provided above the magnetron cathode 14 in the vacuum chamber 12, more specifically above the surface of the target 142 to be sputtered. This filament 20 is, for example, a tungsten (W) wire having a diameter of about 1 mm. The filament 20 is provided so as to extend linearly along the surface of the target 142 to be sputtered, that is, along the horizontal direction, at an appropriate distance from the surface of the target 142 to be sputtered. The distance between the filament 20 and the surface of the target 142 to be sputtered is approximately 5 mm to 50 mm, for example approximately 25 mm. The length dimension of the filament 20 is larger than the diameter of the target 142, strictly speaking, larger than the diameter of the erosion region of the target 142, for example approximately 320 mm. The filament 20 is not limited to being made of tungsten, and may be made of a refractory metal other than tungsten, such as tantalum (Ta) or molybdenum (Mo). In addition, although not shown in the drawings, at either end or both ends of the filament 20, tensioning means for maintaining the linear state of the filament 20 by applying an appropriate tension to the filament 20 tensioning mechanism is provided.

Further, the filament 20, strictly speaking, both ends of the filament 20 are connected outside the vacuum chamber 12 to a cathode power supply device 22 as power supply means for thermionic emission. The cathode power supply device 22 supplies the filament 20 with AC cathode power Ec as power for thermionic emission. Upon receipt of this cathode power Ec, the filament 20 is heated to, for example, 2000° C. or higher to emit thermoelectrons. The maximum capacity of the cathode power supply device 22 is, for example, 2.4 kW (=40 V×60 A). Further, the cathode power Ec is not limited to AC power, and may be DC power.

In addition, the filament 20, for example, one end of the filament 20 is connected outside the vacuum chamber 12 to a discharge power supply device 24 as a discharge power supply means. The discharge power supply 24 uses the vacuum chamber 12 as an anode and the filament 20 as a cathode, and supplies DC discharge power Ed to both of them. The capacity of this discharge power supply device 24 is, for example, 6 kW (=100 V×60 A) at maximum. Like the sputtering power supply 18, this discharge power supply 24 also has three operating modes: constant power mode, constant voltage mode, and constant current mode. That is, the constant power mode is a mode in which the power value of the discharge power Ed is kept constant. The constant voltage mode is a mode in which the discharge voltage Vd, which is the voltage component of the discharge power Ed, is kept constant. The constant current mode is a mode in which the discharge current Id, which is the current component of the discharge power Ed, is kept constant. Here, the discharging power supply 24 is set to operate in constant voltage mode.

In addition, the workpiece 100 is placed above the filament 20 in the vacuum chamber 12 . The object to be processed 100 has a flat substrate 110 and an organic EL element 120 as an electronic element provided on the substrate 110 as will be described later. Then, the object 100 to be processed faces the target 142 to be sputtered through the filament 20 with the part to be processed, more specifically, the part provided with the organic EL element 120 facing downward. placed in the At this time, the workpiece 100, more specifically the substrate 110, is supported by the substrate table 26 as a holding means. The distance between the sputtering surface of the target 142 and the portion of the object 100 to be processed depends on various conditions such as the shapes and dimensions of the target 142 and the object 100 to be processed, but is, for example, 200 mm to 700 mm. degree.

A substantially disk-shaped shutter 28 , for example, is provided at an appropriate position between the filament 20 and the substrate table 26 within the vacuum chamber 12 . The shutter 28 is supported by a shutter driving mechanism (not shown) so that both main surfaces of the shutter 28 extend in the horizontal direction. The shutter drive mechanism drives the shutter 28 under the control of the control unit 30, which will be described later, and more specifically, selectively transitions the shutter 28 between an open state and a closed state. Here, the open state is a state in which the portion to be processed of the object 100 to be processed and the surface to be sputtered of the target 142 are opened. It is exposed on the surface. On the other hand, the closed state is a state in which the portion to be processed of the object 100 to be processed and the surface to be sputtered of the target 142 are closed. It is a state of shielding from

Further, at an appropriate position on the wall of the vacuum chamber 12, for example, at an appropriate position on the wall forming the side surface of the vacuum chamber 12 (the position on the right side in FIG. 1), various kinds of gas containing argon (Ar) gas as a discharge gas are added. A gas introduction pipe 32 is provided for introducing gas into the vacuum chamber 12 . Although detailed illustration is omitted, the gas introduction pipe 32 has an ejection hole for ejecting the gas introduced into the vacuum chamber 12, and the ejection hole is positioned near the filament 20, that is, the It is provided so as to eject gas in the vicinity of the filament 20 . The gas introduction pipe 32 is connected outside the vacuum chamber 12 to a pipe 34 for argon gas and a pipe 36 for nitrogen gas as a reactive gas.

The argon gas pipe 34 is connected to an argon gas supply source (not shown) (for example, an argon gas cylinder). The argon gas pipe 34 is provided with an opening/closing valve 34a as an opening/closing means for opening and closing the inside of the pipe 34, and a flow rate control means for controlling the flow rate of the argon gas flowing through the pipe 34. A mass flow controller 34b is provided. The argon gas pipe 34 cooperates with the gas introduction pipe 32 to constitute discharge gas introduction means. As the argon gas, a high-purity gas (preferably with a purity of 99.999% or higher) is used.

On the other hand, the nitrogen gas pipe 36 is connected to a nitrogen gas supply source (not shown) (for example, a nitrogen gas cylinder). Also in this nitrogen gas pipe 36, an opening/closing valve 36a as an opening/closing means for opening and closing the inside of the pipe 36 and a mass flow control means for controlling the flow rate of the nitrogen gas flowing through the pipe 36 are provided. A controller 36b is provided. This nitrogen gas pipe 36 cooperates with the gas introduction pipe 32 to constitute reaction gas introduction means. As for nitrogen gas, a high-purity gas (preferably having a purity of 99.99% or more) is used.

A control unit 30 as a control means is provided outside the vacuum chamber 12 . This control unit 30 controls the entire magnetron sputtering apparatus 10 . Specifically, the control unit 30 controls the aforementioned shutter driving device. The control unit 30 also controls the sputtering power supply 18 , the cathode power supply 22 and the discharge power supply 24 . Further, the control unit 30 also controls the opening/closing valve 34a and the mass flow controller 34b of the argon gas pipe 34, the opening/closing valve 36a and the mass flow controller 36b of the nitrogen gas pipe 36, and the like. In order to implement these controls, the control unit 30 includes, for example, a CPU (Central Processing Unit) as control execution means (not shown).

According to the magnetron sputtering apparatus 10 having such a configuration, the sealing film 200 for sealing the organic EL element 120 in the object 100 to be processed as shown in FIG. 2 can be formed.

Specifically, the object to be processed 100 includes a flat substrate 110 and an organic EL element 120 provided on the substrate 110 . Substrate 110 is, for example, a transparent glass substrate. An anode 112 is provided on the upper surface (upper surface in FIG. 1) which is one main surface of the substrate 110 . The anode 112 is a thin transparent electrode, such as an indium tin oxide (ITO) film. An organic EL element 120 is provided on the anode 112 . Substrate 110 may be a transparent substrate other than a transparent glass substrate, such as a transparent resin substrate. In addition, the anode 112 is not limited to indium tin oxide, and may be a transparent conductive film formed of a material other than indium tin oxide, such as zinc oxide (ZnO), tin oxide (SnO), polyaniline, and graphene.

The organic EL element 120 is a light-emitting element having a two-layer structure in which, for example, a hole transport layer (HTL: Hole Transfer Layer) 122 and a light-emitting layer (EML: EMIssive Layer) 124 are laminated in this order. Furthermore, a cathode 126 is provided on the light emitting layer 124 . Cathode 126 is, for example, an aluminum film with a thickness dimension of 200 nm. When a predetermined signal (voltage) is supplied from the signal source 130 to the cathode 126 and the anode 112, the light emitting layer 124 emits light. Light emitted from the light emitting layer 124 is output to the substrate 110 side. That is, the lower surface (the lower surface in FIG. 1), which is the other main surface of the substrate 110, becomes the light emitting surface of the organic EL element 120. As shown in FIG. Such a so-called bottom emission type organic EL element 120 is used for a lighting device, a display device, and the like. Note that the organic EL element 120 is not limited to a two-layer structure, and may have another structure including an electron transport layer (ETL) or the like.

The organic EL element 120 deteriorates when exposed to moisture, oxygen, or the like. Therefore, a sealing film 200 is formed to seal the organic EL element 120 between the substrate 110 and the organic EL element 120 in order to protect the organic EL element from moisture, oxygen, and the like. The sealing film 200 includes, for example, an aluminum nitride (AlN) layer as a first layer 202, an aluminum layer as a second layer 204, an aluminum nitride layer as a third layer 206, and a fourth layer 206, as shown in FIG. An aluminum layer as the layer 208 and an aluminum nitride layer as the fifth layer 210 are laminated in this order to form a five-layer laminated film. Both the aluminum nitride layer and the aluminum layer have barrier properties against moisture, oxygen, and the like. Function. The second layer 204 and the fourth layer 208, which are aluminum layers, function as buffer layers for improving the coverage of the first layer 202, the third layer 206 and the fifth layer 210 as barrier layers. Since the first layer 202, which is the bottom layer, must be an insulating material, an aluminum nitride layer is formed as the first layer 202. FIG.

In order to form such a sealing film 200 , first, the workpiece 100 before the sealing film 200 is formed is placed in the vacuum chamber 12 . At this time, the object 100 to be processed is arranged with the part where the organic EL element 120 is provided directed downward as described above. That is, the substrate 110 is held by the substrate table 26 in such a manner. After that, the vacuum chamber 12 is sealed. Then, the inside of the vacuum chamber 12 is evacuated by a vacuum pump to a pressure of about 1×10 ⁻³ Pa, for example.

After this so-called evacuation, a film forming process for forming an aluminum nitride layer as the first layer 202 is performed. For that purpose the shutter 28 is closed. It should be noted that the shutter 28 may be in either closed or open state during the evacuation described above. Then, the filament 20 is supplied with the cathode power Ec. As a result, the filament 20 is heated and thermal electrons are emitted from the filament 20 . At the same time, the vacuum chamber 12 is used as an anode and the filament 20 is used as a cathode, and discharge power Ed is supplied to both of them. As a result, thermoelectrons emitted from the filament 20, which is the cathode, are directed toward the wall of the vacuum chamber 12, which is the anode. accelerated towards In this state, argon gas is introduced into the vacuum chamber 12 through the gas introduction pipe 32 , more precisely, through the argon gas pipe 34 and the gas introduction pipe 32 . Then, the accelerated thermal electrons collide with argon gas particles, and the argon gas particles are ionized by the impact to generate plasma 300 .

Here, a magnetic field is formed in the space near the sputtered surface of the target 142 including the periphery of the filament 20 as described above. Therefore, thermoelectrons emitted from the filament 20 undergo spiral motion (cycloidal motion or trochoidal motion) under the influence of this magnetic field. This increases the frequency at which thermal electrons collide with argon gas particles, densifying the plasma 300 . The discharge mode of such plasma 300 is a low-voltage, high-current arc discharge. Here, a captured image of the filament 20 and its surroundings when the plasma 300 is generated (during discharge) is shown in FIG. 4 side by side with a captured image when the plasma 300 is not generated (during non-discharge). . As can be seen from FIG. 4, particularly from FIG. 4A, which is a photographed image when plasma 300 is generated, it is recognized that high-density plasma 300 is generated around filament 20. be done.

In the state where high-density plasma 300 is generated by such arc discharge, sputtering power Es is supplied to both the vacuum chamber 12 as an anode and the magnetron cathode 14 as a cathode. Then, the argon ions in the plasma 300 are accelerated toward the sputtered surface of the target 142 of the magnetron cathode 14 and collide with the sputtered surface. Due to the impact, particles of aluminum, which is the material of the target 142, are ejected from the surface of the target 142 to be sputtered, that is, are sputtered. The sputtered aluminum particles, so-called sputtered particles, fly toward the object 100 facing the surface of the target 142 to be sputtered. At this point, however, the shutter 28 is in a closed state, so the shutter 28 blocks the flight of the aluminum particles. Moreover, although it is not clear from each drawing including FIG. 1, glow discharge is induced in the space near the surface of the target 142 to be sputtered by supplying the sputtering power Es. That is, the plasma 300 is in a form that includes a component due to arc discharge and a component due to glow discharge.

In this state, nitrogen gas is further introduced into the vacuum chamber 12 through the gas introduction pipe 32 , more precisely, through the nitrogen gas pipe 36 and the gas introduction pipe 32 . Particles of this nitrogen gas are then also ionized to form plasma 300 . Nitrogen particles containing nitrogen ions in the plasma 300 fly toward the workpiece 100 together with the aluminum particles, which are the sputtered particles. However, the flight of the nitrogen particles is also blocked by the closed shutter 28 .

Then, when the plasma 300 is stabilized, the shutter 28 is opened. As a result, the aluminum particles and nitrogen particles flying toward the object 100 to be processed adhere to and accumulate on the part to be processed of the object 100 to be processed. As a result, an aluminum nitride layer is formed as a first layer 202, which is a reaction film (compound) of aluminum particles and nitrogen particles, on the part of the object 100 to be treated, that is, to cover the organic EL element 120. .

After the aluminum nitride layer having a predetermined thickness is formed by the film formation process for forming the aluminum nitride layer as the first layer 202, subsequently, the aluminum layer is formed as the second layer 204. is performed. For this purpose the shutter 28 is closed again. After that, the introduction of nitrogen gas into the vacuum chamber 12 is stopped. Then, when the plasma 300 is stabilized, the shutter 28 is opened. As a result, an aluminum layer is formed as a second layer 204, which is a single-element film composed only of aluminum particles, on the portion to be processed of the object 100 to be processed, that is, on the aluminum nitride layer as the first layer 202. Next, as shown in FIG.

After the aluminum layer having a predetermined thickness dimension is formed by the film formation process for forming the aluminum layer as the second layer 204, subsequently, the film forming process for forming the aluminum nitride layer as the third layer 206 is performed. A film forming process is performed. For this purpose the shutter 28 is closed again. After that, nitrogen gas is again introduced into the vacuum chamber 12 . Then, when the plasma 300 stabilizes, the shutter 28 is opened again. As a result, an aluminum nitride layer as the third layer 206 is formed on the portion to be processed of the object 100 to be processed, that is, on the aluminum layer as the second layer 204 .

After the aluminum nitride layer having a predetermined thickness is formed by the film formation process for forming the aluminum nitride layer as the third layer 206, subsequently, the aluminum nitride layer for forming the fourth layer 208 is formed. A film forming process is performed. For this purpose the shutter 28 is closed again. After that, the introduction of nitrogen gas into the vacuum chamber 12 is stopped again. Then, when the plasma 300 stabilizes, the shutter 28 is opened again. As a result, an aluminum layer as the fourth layer 208 is formed on the portion to be processed of the object 100 to be processed, that is, on the aluminum nitride layer as the third layer 206 .

After the aluminum layer having a predetermined thickness is formed by the film formation process for forming the aluminum layer as the fourth layer 208 , subsequently, a film formation process for forming the aluminum nitride as the fifth layer 210 is performed. Membrane treatment is performed. For this purpose the shutter 28 is closed again. After that, nitrogen gas is again introduced into the vacuum chamber 12 . Then, when the plasma 300 stabilizes, the shutter 28 is opened again. As a result, an aluminum nitride layer as the fifth layer 210 is formed on the portion to be processed of the object 100 to be processed, that is, on the aluminum oxide layer as the fourth layer 208 .

After the aluminum nitride layer having a predetermined thickness is formed by the film formation process for forming the aluminum nitride layer as the fifth layer 210, that is, after the sealing film 200 of all five layers is formed, Shutter 28 is closed again. After that, introduction of argon gas and nitrogen gas into the vacuum chamber 12 is stopped. At the same time, the supply of the sputtering power Es, the discharge power Ed, and the cathode power Ec is stopped. Thereby, the plasma 300 disappears. Then, after the pressure in the vacuum chamber 12 is returned to the atmospheric pressure over an appropriate time (for example, about several tens of minutes), the inside of the vacuum chamber 12 is opened to the outside, and A workpiece 100 is taken out. With this, a series of processes including the film forming process for forming the sealing film 200 are completed.

By the way, according to the first embodiment, a very dense sealing film 200 can be formed. For example, focusing on the aluminum nitride layer as the first layer 202, in the film forming process for forming this aluminum nitride layer, as described above, aluminum particles as sputter particles are ejected from the surface of the target 142 to be sputtered. . The kicked-out aluminum particles fly toward the object 100 to be processed, but on the way, pass through the high-density plasma 300 (including components) generated by the arc discharge. The aluminum particles are thereby activated, at least to have higher energies than the ground state, and are particularly efficiently radicalized or ionized. Similarly, nitrogen gas particles are also activated by the high density plasma 300 and radicalized or ionized particularly efficiently. Since the particles radicalized or ionized in this way are highly reactive, the efficient generation of such highly reactive particles allows the aluminum to form the aluminum nitride layer as the first layer 202. Mutual binding force between particles and nitrogen particles is strengthened. As a result, the aluminum nitride layer as the first layer 202 is densified. The same is true for the aluminum nitride layer as the third layer 206 and the aluminum nitride layer as the fifth layer 210 .

In addition, for example, focusing on the aluminum layer as the second layer 204, even in the film formation process for forming this aluminum layer, the aluminum particles, which are sputtered particles, are activated by the high-density plasma 300 generated by arc discharge, have high energy. By imparting high energy to the aluminum particles, which are sputtered particles, in this way, the aluminum layer as the second layer 204 formed of the aluminum particles is densified. This also applies to the aluminum layer as the fourth layer 208 .

On the other hand, according to the first embodiment, damage to the object 100 to be processed, especially to the organic EL element 120, caused by the plasma 300 can be suppressed. To explain this, FIG. 5 shows the relationship between the discharge power Ed and the sputtering current Is, which is the current component of the sputtering power Es, and the sputtering voltage Vs, which is the voltage component of the discharge power Ed and the sputtering power Es. shows the relationship between In FIG. 5, the thick solid line with circles indicates the relationship between the discharge power Ed and the sputtering current Is. A thick dashed line with squares indicates the relationship between the discharge power Ed and the sputtering voltage Vs.

In FIG. 5, for example, focusing on the relationship between the discharge power Ed and the sputtering current Is (bold solid line with circles), the larger the discharge power Ed, the greater the sputtering current Is. This is because some of the ions in the plasma 300 generated by arc discharge flow into the target 142 (magnetron cathode 14). Focusing on the relationship between the discharge power Ed and the sputtering voltage Vs (bold dashed line with a square mark), the larger the discharge power Ed, in other words, the larger the sputtering current Is, the lower the sputtering voltage Vs. . This is because the sputtering power supply 18, which is the supply source of the sputtering power Es, operates in the constant power mode as described above. From these facts, it can be seen that the sputtering voltage Vs is lowered by inducing the arc discharge, and that the higher the density of the plasma 300 caused by the arc discharge, the more the sputtering voltage Vs is lowered.

Note that FIG. 5 shows the relationship when the target 142 is made of titanium (Ti), the pressure in the vacuum chamber 12 is 0.2 Pa, and the sputtering power Es (=Vs×Is) is 1 kW. Similar relationships apply when the target 142 is aluminum. The discharging power supply 24, which is the supply source of the discharging power Ed, operates in the constant voltage mode as described above. In this case, the discharging power Ed itself (power value) is controlled by the cathode power Ec. be. That is, when the cathode power Ec is increased or decreased, the heating temperature of the filament 20 changes, and accordingly the amount of thermal electrons emitted from the filament 20 changes. When the amount of thermoelectrons emitted from the filament 20 changes, the amount of ions in the plasma 300 changes. Ed itself (=Vd×Id) increases or decreases.

Now, when the sputtering voltage Vs decreases, the energy of the electrons incident on the processed portion of the processed object 100 including the organic EL element 120 is reduced. As a result, damage to the object 100 to be processed, especially to the organic EL element 120, is suppressed. Specifically, when the sputtered surface of the target 142 is sputtered, not only aluminum particles as sputtered particles but also secondary electrons are ejected from the sputtered surface. Then, the secondary electrons also fly toward the object 100 to be processed and enter the part of the object 100 to be processed. The secondary electrons have energy corresponding to the sputtering voltage Vs, that is, the higher the sputtering voltage Vs (strictly, the larger the absolute value of the sputtering voltage Vs), the greater the energy. The greater the energy of the secondary electrons, the more damage is given to the object 100 to be processed, and it is feared that the temperature of the object 100 to be processed increases. According to the first embodiment, since the sputtering voltage Vs can be lowered, the energy of the secondary electrons incident on the portion to be processed of the object 100 to be processed can be reduced. Damage to the object 100 to be processed can be suppressed.

In short, according to the first embodiment, it is possible to form an extremely dense sealing film 200 while suppressing damage to the organic EL element 120 .

Incidentally, in a configuration in which no arc discharge is induced, for example, in a general magnetron sputtering configuration in which plasma is generated only by glow discharge, unlike the first embodiment in which the arc discharge is induced, the organic EL element 120 will inflict great damage. In addition, with the configuration of the general magnetron sputtering method, it is not possible to form the extremely dense sealing film 200 as in the first embodiment.

For example, in the configuration shown in FIG. 1, by not supplying the cathode power Ec and the discharge power Ed, the configuration of the general magnetron sputtering method referred to here is realized. In the configuration of this general magnetron sputtering method, plasma 300 is generated by supply of sputtering power Es, and this plasma 300 is in the form of high-voltage, low-current glow discharge. In the state where the plasma 300 is generated only by glow discharge, the sputtering voltage Vs, which is the voltage component of the sputtering power Es, is extremely high compared to the case where the plasma 300 is generated by the arc discharge described above. This can also be seen from FIG. 5 that the sputtering voltage Vs is extremely high when the discharge power Ed is zero (Ed=0). When the sputtering voltage Vs is thus high, the energy of the secondary electrons incident on the portion to be processed of the object 100 to be processed becomes high. As a result, the object 100 to be processed, especially the organic EL element 120, is greatly damaged. Moreover, since the plasma 300 generated by glow discharge has a much lower density than the plasma 300 generated by arc discharge, it is impossible to form a dense sealing film 200 .

In order to confirm this, the following experiment was conducted.

First, a sealing film 200 including layers 202, 204, 206, 208 and 210 was formed under the conditions shown in FIG. The pressure in the vacuum chamber 12 at this time is 0.2 Pa.

In addition, as a first comparative example, a sealing film 200 having the same film thickness as shown in FIG. 6 was formed by the configuration of a so-called glow discharge type magnetron sputtering method realized in the manner described above. . The film formation conditions at this time are that the discharge voltage Vd is zero (Vd=0), the discharge current Id is zero (Id=0), and the respective layers 202, 204, 206, 208 and 210 are It is the same as shown in FIG. 6, except that the deposition time is set appropriately.

Furthermore, as a second comparative example, FIG. 6 shows the film thicknesses of the respective layers 202, 204, 206, 208 and 210 by the general glow discharge type magnetron sputtering method realized in the manner described above. A sealing film 200 with half the value was formed. That is, the sealing film 200 was formed in which the thickness of each of the first layer 202, the third layer 206 and the fifth layer 210 was 25 μm, and the thickness of each of the second layer 204 and the fourth layer 208 was 50 μm. . The film formation conditions at this time are also that the discharge voltage Vd is zero (Vd=0), the discharge current Id is zero (Id=0), and that each of the layers 202, 204, 206, 208 and 210 6 is the same as shown in FIG.

Then, the respective organic EL elements 120 having the sealing films 200 formed thereon were actually operated, and their light emitting states were observed for four days. The results are shown in FIG. Each image shown in FIG. 7 is an image obtained by observing the light emitting state of the organic EL element 120 from the (lower surface) side of the substrate 110 with a microscope. In addition, in each image shown in FIG. 7, the relatively large black dot appearing near the center is a reference point intentionally added to facilitate identification of the observation position with the microscope.

As shown in FIG. 7, for the organic EL element 120 according to the first example, for example, no particular change was observed until the third day, and some dark spots (small black dots) were observed on the fourth day. can be seen. These dark spots are presumed to be caused by some defects such as pinholes in the sealing film 200 . From this, it can be seen that according to the first embodiment, the sealing film 200 capable of maintaining the quality of the organic EL element 120 for at least three days can be formed. Such a sealing film 200 is sufficiently practical for so-called temporary sealing for temporarily sealing the organic EL element 120 .

On the other hand, for example, in the organic EL element 120 of the first comparative example, although no particular change was observed on the first day, dark spots were observed from the second day. and appear conspicuously, including size. Further, in the organic EL element 120 of the second comparative example, dark spots appear more conspicuously than in the first comparative example. Thus, the conspicuous appearance of dark spots in the organic EL elements 120 of the first and second comparative examples is due to the damage caused by the (glow discharge) plasma 300 during the formation of the sealing film 200. It is inferred. In addition, in the first comparative example and the second comparative example, the fact that the dense sealing film 200 is not formed, in other words, only the sealing film 200 with many defects is formed is another reason why the dark spots appear conspicuously. It is inferred that Naturally, the organic EL element 120 in which such dark spots remarkably appear cannot be put to practical use.

As described above, according to the magnetron sputtering apparatus 10 according to the first embodiment, the sealing film 200 that seals the organic EL element 120 can be sufficiently put into practical use while suppressing damage to the organic EL element 120. level can be formed.

In the first embodiment, the vacuum chamber 12 may be used as an anode, and the workpiece 100 (substrate table 26) may be used as an anode, and bias power may be supplied to both of them. This can improve the adhesion of the sealing film 200 (layers 202, 204, 206, 208 and 210) to the object 100 to be processed.

Further, in the first embodiment, in accordance with the timing of turning on/off the introduction of nitrogen gas into the vacuum chamber 12, that is, during a series of film forming processes for forming the sealing film 200, Although the shutter 28 is driven to open and close, it is not limited to this. For example, the shutter 28 is driven to open and close only at the start and end of a series of film forming processes for forming the sealing film 200, and the shutter 28 continues during the period in which the series of film forming processes is being performed. It may be opened temporarily (always).

[Second embodiment]
Next, a second embodiment of the invention will be described with reference to FIG.

As shown in FIG. 8, particularly as shown in FIG. 8A, the magnetron sputtering apparatus 50 according to the second embodiment has an elongated shape extending in the horizontal direction (horizontal direction in FIG. 8). A vacuum chamber 52 is provided. The interior of the vacuum chamber 52 is partitioned into a plurality of, for example five, film formation chambers 56, 56, . . . In other words, the five film forming chambers 56, 56, . . . A vacuum chamber 52 including these film forming chambers 56, 56, . A wall of the vacuum chamber 52 is grounded. In addition, hereinafter, the film forming chambers 56, 56, . . . ”, “fourth film forming chamber” and “fifth film forming chamber”.

In addition, the magnetron sputtering apparatus 50 according to the second embodiment includes a transport mechanism 58 as transport means for transporting the object 100 to be processed. The conveying mechanism 58 is arranged so that the workpiece 100 sequentially passes through the film forming chambers 56, 56, . , the object to be processed 100 is transported. The object 100 to be processed in the second embodiment is similar to that in the first embodiment. That is, the workpiece 100 in the second embodiment also includes a flat substrate 110 and an organic EL element 120 provided on the substrate 110, as shown in FIG. Although not shown in detail, the transport mechanism 58 transports the object 100 to be processed with the portion of the object 100 where the organic EL element 120 is provided facing downward. As such a conveying mechanism 58, an appropriate mechanism such as a belt type, roller type, or chain type can be employed.

Each partition wall 54 is provided with an appropriate insertion portion 60 for inserting the workpiece 100 transported by the transport mechanism 58 so that the transport path for the workpiece 100 transported by the transport mechanism 58 is secured. be provided. By providing the insertion portion 60, the insides of the two adjacent film formation chambers 56 and 56 are communicated with each other. It is designed so as not to affect the later-described film forming process inside. In particular, in order to reduce the conductance in the insertion portion 60 and reduce the flow of gas through the insertion portion 60, for example, a flat plate shape having a flat portion along the direction in which the workpieces 100 are conveyed by the conveying mechanism 58 is provided. A collar portion (portion formed in a substantially T-shape in FIG. 8) 60a is provided. In addition, in the film forming chamber 56 through which the object 100 to be processed first passes (accommodated), that is, the first film forming chamber 56 on the right end in FIG. A carry-in port 62 serving as an entrance to the is provided. The carry-in port 62 is provided with a carry-in side buffer chamber (not shown) as a relay chamber that mediates between the inside of the first film forming chamber 56 and the outside under atmospheric pressure. Similarly, in the film forming chamber 56 through which the object 100 passes last, that is, the fifth film forming chamber 56 on the left end in FIG. A carry-out port 64 is provided. The carry-out port 64 is provided with a carry-out side buffer chamber (not shown) serving as a relay chamber that mediates between the inside of the fifth film forming chamber 56 and the outside at atmospheric pressure.

Further, each film formation chamber 56 is provided with an exhaust port 66 . Although not shown, the exhaust port 66 is connected to a vacuum pump as an exhaust means via an exhaust pipe outside the vacuum chamber 52 (the film forming chambers 56, 56, . . . ). As the vacuum pump, a turbo-molecular pump, for example, is employed as the main exhaust pump, as in the first embodiment. Further, a pressure control device as pressure control means for controlling the pressure in the film forming chamber 56 is provided in the middle of each exhaust pipe. In FIG. 8, the exhaust port 66 is provided in the wall forming the lower surface of each film forming chamber 56, but the position of the exhaust port 66 is not limited to this.

In addition, each film formation chamber 56 is provided with a gas introduction pipe 68 for introducing an appropriate gas into the film formation chamber 56 . However, argon gas as a discharge gas and nitrogen gas as a reactive gas are introduced into the first film forming chamber 56, the third film forming chamber 56 and the fifth film forming chamber 56, respectively. Therefore, although illustration is omitted, the gas introduction pipes 68 provided in each of the first film forming chamber 56, the third film forming chamber 56, and the fifth film forming chamber 56 supply argon gas outside the vacuum chamber 52. and a pipe for nitrogen gas. On the other hand, only argon gas as a discharge gas is introduced into the second film forming chamber 56 and the fourth film forming chamber 56 . Therefore, although illustration is omitted, the gas introduction pipes 68 provided in each of the second film forming chamber 56 and the fourth film forming chamber 56 are connected to piping for argon gas outside the vacuum chamber 52. . As the argon gas and the nitrogen gas, high-purity gases (preferably having a purity of 99.999% or more) are used.

A discharge unit 70 is provided in each film forming chamber 56 . This discharge unit 70 has a magnetron cathode 72, an earth shield 74, and a filament 76, as shown in FIG. 8(B).

Magnetron cathode 72 is similar to magnetron cathode 14 in the first embodiment. That is, the magnetron cathode 72 has a high-purity aluminum target 722 and a magnet unit 724 provided behind the target 722 (lower side in FIG. 8B). The target 722 may be roughly disk-shaped like the target 142 in the first embodiment, or may be roughly rectangular plate-shaped. Then, the magnet unit 724 firmly holds the target 722 on the back side of the target 722 . In addition, the magnet unit 724 incorporates a permanent magnet (not shown) and forms a magnetic field in the space near the surface of the target 722 to be sputtered (the upper surface in FIG. 8B). The magnet unit 724 is fixed to the wall forming the lower surface of the vacuum chamber 12 (film formation chamber 56), for example, with the surface of the target 722 to be sputtered facing upward. Also, the magnet unit 724 is attached with a water cooling mechanism (not shown) for cooling the entire magnetron cathode 72 including the magnet unit 724 .

The magnetron cathode 72 is also connected outside the vacuum chamber 52 to a sputtering power supply 78 similar to that in the first embodiment. The sputtering power supply 78 uses the vacuum chamber 52 as an anode and the magnetron cathode 72 as a cathode, and supplies DC sputtering power Es to both of them. The sputter power supply 78 has three modes of operation: constant power mode, constant voltage mode and constant current mode, and is set here to operate in the constant power mode.

The ground shield 74 covers the magnetron cathode 72, like the ground shield 16 in the first embodiment, except for the sputtered surface of the target 722, in other words, with the sputtered surface exposed. The earth shield 74 is made of metal having high mechanical strength, corrosion resistance and heat resistance, such as stainless steel such as SUS304. At the same time, the earth shield 74 is in a state of being electrically insulated from the magnetron cathode 72 and electrically connected to the vacuum chamber 12 .

The filament 76 is similar to the filament 20 in the first embodiment, that is, it is, for example, a tungsten linear body having a diameter of about 1 mm. The filament 76 is provided so as to extend linearly along the surface of the target 722 to be sputtered, that is, along the horizontal direction, at an appropriate distance from the surface of the target 722 to be sputtered. Both ends or either end of the filament 76 are provided with a tensioning mechanism (not shown) that maintains the linear state of the filament 76 by applying an appropriate tension to the filament 76 .

Also, the filament 76, strictly speaking, both ends of the filament 76 are connected outside the vacuum chamber 52 to the same cathode power supply 80 as in the first embodiment. The cathode power supply 80 supplies AC cathode power Ec to the filament 76 . As a result, the filament 76 is heated to, for example, 2000° C. or higher and emits thermal electrons.

At the same time, the filament 76, more specifically, one end of the filament 76, is connected outside the vacuum chamber 52 to the same discharge power supply 82 as in the first embodiment. The discharge power supply 82 uses the vacuum chamber 52 as an anode and the filament 76 as a cathode, and supplies DC discharge power Ed to both of them. This discharging power supply 82 also has three operating modes, constant power mode, constant voltage mode and constant current mode, and is set to operate in the constant voltage mode here.

With the magnetron sputtering apparatus 50 having such a configuration, as with the magnetron sputtering apparatus 10 according to the first embodiment, a sealing film for sealing the organic EL element 120 in the object 100 to be processed as shown in FIG. 200 can be formed. This sealing membrane 200 has five layers 502, 504, 506, 508 and 510 as in the first embodiment, ie as shown in FIG.

That is, according to the magnetron sputtering apparatus 50 according to the second embodiment, as described above, the workpiece 100 is transported by the transport mechanism 58 so as to sequentially pass through the film forming chambers 56, 56, . be done. At this time, the object 100 to be processed is conveyed with the portion to be processed, where the organic EL element 120 is provided, directed downward. Then, first, a film forming process for forming an aluminum nitride layer as the first layer 202 is performed in the first film forming chamber 56 . The film formation process for forming this aluminum nitride layer is the same as in the first embodiment. Subsequently, a film forming process for forming an aluminum layer as the second layer 204 is performed in the second film forming chamber 56 . The procedure for the film forming process for forming this aluminum layer is also the same as in the first embodiment. Further, a film forming process for forming an aluminum nitride layer as the third layer 206 is performed in the third film forming chamber 56, and an aluminum layer as the fourth layer 208 is formed in the fourth film forming chamber 56. A film forming process is performed for the formation. Then, a film forming process for forming an aluminum nitride layer as the fifth layer 210 is performed in the fifth film forming chamber 56 . In this manner, the workpiece 100 sequentially passes through the film forming chambers 56, 56, .

The magnetron sputtering apparatus 50 according to the second embodiment, which forms the sealing film 200 in such a manner, is suitable for mass production. The sealing film 200 formed by the mass production type magnetron sputtering apparatus 50 is also extremely dense, like the one formed by the so-called batch processing type magnetron sputtering apparatus 10 according to the first embodiment. Furthermore, although illustration is omitted, arc discharge plasma 300 is generated in each of the film forming chambers 56, but the damage to the object 100, especially the organic EL element 120, caused by this plasma 300 is Suppressed. As a result, a sealing film 200 that is sufficiently practical for temporary sealing is formed.

In short, the mass production type magnetron sputtering apparatus 50 according to the second embodiment suppresses the damage to the organic EL element 120 and the organic EL element 120 as in the case of the batch processing type magnetron sputtering apparatus 10 according to the first embodiment. The sealing film 200 that seals the EL element 120 can be formed at a sufficiently practical level.

In the second embodiment, similarly to the first embodiment, the vacuum chamber 52 is used as an anode, and the workpieces 100 (transport mechanisms 58) are used as cathodes, and bias power is supplied to both of them. good too. However, since the temperature of the workpiece 100 may rise due to the supply of this bias power, it is necessary to carefully consider the supply of the bias power, including the influence of this.

Further, by providing an opening/closing gate in each partition wall 54 (insertion portion 60), the degree of sealing in each film formation chamber 56 may be improved. In this case, it is desirable to provide similar open/close gates at the inlet 62 of the first film forming chamber 56 and the outlet 64 of the fifth film forming chamber.

In the second embodiment, an in-line system in which a plurality of film formation chambers 56, 56, . . . The present invention can also be applied to mass-production devices other than in-line devices such as known load-lock and multi-chamber devices. In this case, appropriate storage means for storing the object 100 to be processed is employed in each film formation chamber according to the structure of the apparatus.

[Third embodiment]
A third embodiment of the present invention will now be described with reference to FIG.

As shown in FIG. 9, a magnetron sputtering apparatus 500 according to the third embodiment is suitable for forming a sealing film 200 similar to that described above on a flexible elongated film 400 as a substrate. , roll-up type (also called "roll-to-roll type"). This winding-type magnetron sputtering apparatus 500 includes a vacuum chamber 302 having a suitable shape, for example, a substantially rectangular parallelepiped shape. The vacuum chamber 302 is made of metal having relatively high mechanical strength, corrosion resistance and heat resistance, such as stainless steel such as SUS304. Although not shown, the walls of the vacuum chamber 302 are grounded. The film 400 is made of a transparent resin such as PET (Poly Ethylene Terephthalate) resin, but is not limited to this.

A transport mechanism 303 for transporting the film 400 is provided inside the vacuum chamber 302 . The conveying mechanism 303 includes a generally cylindrical cooling roll (also called a “can roll” or “cooling drum”) 304 , an unwinding roll 306 that supplies (unwinds) the film 400 to the cooling roll 304 , and the and a take-up roll 308 that takes up the film 400 from the chill roll 304 . Appropriate intermediate rolls are provided between the cooling roll 304 and the unwinding roll 306, for example, an unwinding side free roll 309, an unwinding side tension detection roll 310 and an unwinding side feed roll 312 are provided. The unwinding-side free roll 309, the unwinding-side tension detection roll 310, and the unwinding-side feed roll 312 are arranged along the feeding direction of the film 400 from the unwinding roll 306 to the cooling roll 304, that is, along the conveying direction 400a of the film 400. are appropriately provided in this order. In addition, between the cooling roll 304 and the take-up roll 308, suitable intermediate rolls such as a take-up feed roll 313, a take-up tension detection roll 314 and a take-up free roll 316 are provided. . The take-up feed roll 313, the take-up tension detection roll 314, and the take-up free roll 316 are arranged in the transport direction 400a of the film 400, which is the winding direction of the film 400 from the cooling roll 304 by the take-up roll 308. , are appropriately provided in this order.

According to the conveying mechanism 303 as described above, the film 400 unwound from the unwinding roll 306 is transferred to the unwinding side free roll 309, the unwinding side tension detection roll 310, the unwinding side feed roll 312, the cooling roll 304, and the winding. It is conveyed while closely contacting the outer peripheral surfaces of the take-up feed roll 313 , the take-up side tension detection roll 314 and the take-up side free roll 316 , and wound up by the take-up roll 308 . In this process, an appropriate tension (not shown) is applied so that an appropriate tension is applied to the film 400, more specifically, so that the results of detection by the unwinding-side tension detection roll 310 and the take-up-side tension detection roll 314 are constant. The tension is adjusted by an adjusting mechanism. At the same time, a drive motor (not shown) as an unwinding drive means for driving the unwinding roll 306 and a drive motor (not shown) for driving the winding roll 308 are used so that the transport speed of the film 400 is constant. A separate drive motor as winding drive means is controlled accordingly. The chill roll 304 is driven at a constant rotational speed, ie another drive motor as chill roll drive means for driving the chill roll is controlled to do so.

Note that the film 400 is transported with the surface on which the organic EL elements 120 are arranged facing outward in the section where the film 400 is brought into close contact with the outer peripheral surface of the cooling roll 304. The orientation of both the front and back sides of the film 400 is determined. Also, the cooling roll 304 has a cooling mechanism as a substrate cooling means (not shown). This cooling mechanism appropriately cools the outer peripheral surface of the cooling roll 304 and, in turn, appropriately cools the film 400 that is in close contact with the outer peripheral surface of the cooling roll 304 . Such a cooling mechanism includes, for example, a water-cooled type, but is not limited to this.

Furthermore, although illustration is omitted, before the film 400 is brought into close contact with the outer peripheral surface of the cooling roll 304, the surface of the film 400 on which the organic EL elements 120 are arranged is masked. Specifically, for example, a mask film made of resin is attached to the surface of the film 400 on which the organic EL element 120 is arranged, before (upstream) the unwinding side feed roll 312 in the conveying direction 400a of the film 400. be worn. Therefore, the film 400 is supplied to the cooling roll 304 with the mask film adhered to the surface on which the organic EL elements 120 are arranged, and is brought into close contact with the outer peripheral surface of the cooling roll 304 . Then, the mask film is peeled off from the film 400 at the front side (downstream side) of the take-up feed roll 313 in the transport direction 400a of the film 400, that is, the masking is released. Such masking techniques are well known and will not be described in further detail.

In addition, the interior of the vacuum chamber 302 is partitioned by a suitable partition wall 318 into an unwinding/winding chamber 320 and a plurality of, for example five, film forming chambers 322, 322, . Among them, the unwinding/winding chamber 320 is an upper space inside the vacuum chamber 302, and more specifically, the unwinding roll 306, the unwinding side free roll 309, the unwinding side tension detection roll 310, and the unwinding side feed. It is a space that includes a roll 312 , an upper part of the cooling roll 304 , a winding-side feed roll 313 , a winding-side tension detection roll 314 and a winding-side free roll 316 . On the other hand, each film forming chamber 322, 322, . . . is a space formed by dividing the lower space inside the vacuum chamber 302 into five. These film forming chambers 322, 322, . be done. In addition, hereinafter, the respective film forming chambers 322, 322, . They may be expressed as "third film formation chamber", "fourth film formation chamber" and "fifth film formation chamber".

Between each partition wall 318 and the outer peripheral surface of the cooling roll 304, there is provided a gap through which the film 400, which is transported in close contact with the outer peripheral surface of the cooling roll 304, is inserted, that is, an insertion portion 324. be done. However, by providing this insertion portion 324, the two adjacent film forming chambers 322 and 322, or the film forming chamber at the end of each of the film forming chambers 322, 322, . . . Alternatively, the inside of the fifth film forming chamber) 322 and the inside of the unwinding/winding chamber 320 are communicated with each other. As a result, there is a concern that the film forming process, which will be described later, in each film forming chamber 322 is somewhat affected. The insertion portion 324, including its shape and dimensions, is appropriately designed so that this concern is suppressed as much as possible. In particular, in order to reduce the conductance at the insertion portion 324 and reduce the flow of gas through the insertion portion 324, for example, a collar portion having a flat or curved surface (approximately T in FIG. 9) along the outer peripheral surface of the cooling roll 304 A character-shaped portion 324a is provided. Instead of providing this flange portion 324a, or in addition to this, the thickness of each partition wall 318 may be designed to be large. Each partition wall 318 is made of, for example, the same material as the vacuum chamber 302 and is formed integrally with the vacuum chamber 302 .

An exhaust port 326 is provided in the unwinding/winding chamber 320 . Although not shown, the exhaust port 326 is connected to a vacuum pump as an exhaust means outside the vacuum chamber 302 via an exhaust pipe. A turbomolecular pump, for example, is employed as the vacuum pump, especially as the main evacuation pump. In addition, a pressure control device as pressure control means for controlling the pressure in the unwinding/winding chamber 320 is provided in the middle of the exhaust pipe.

In addition, the unwinding/winding chamber 320 is provided with a gas introduction pipe 328 for introducing argon gas, which is an inert gas, into the unwinding/winding chamber 320 . Although not shown, the gas introduction pipe 328 is connected to a pipe for argon gas outside the vacuum chamber 302 .

An exhaust port 330 is also provided in each film formation chamber 322 . Although not shown, the exhaust port 330 is connected to a vacuum pump as an exhaust means outside the vacuum chamber 302 via an exhaust pipe. A turbomolecular pump, for example, is employed for this vacuum pump, inter alia, as the main exhaust pump. Further, a pressure control device as pressure control means for controlling the pressure in the film forming chamber 322 is provided in the middle of each exhaust pipe.

Furthermore, each film formation chamber 322 is provided with a gas introduction pipe 332 for introducing an appropriate gas into the film formation chamber 322 . However, argon gas as a discharge gas and nitrogen gas as a reactive gas are introduced into the first film forming chamber 322 , the third film forming chamber 322 and the fifth film forming chamber 322 . Therefore, although illustration is omitted, the gas introduction pipes 332 provided in each of the first film forming chamber 322, the third film forming chamber 322, and the fifth film forming chamber 322 supply argon gas outside the vacuum chamber 302. and a pipe for nitrogen gas. On the other hand, only argon gas as a discharge gas is introduced into the second film forming chamber 322 and the fourth film forming chamber 322 . Therefore, although illustration is omitted, the gas introduction pipes 332 provided in each of the second film forming chamber 322 and the fourth film forming chamber 322 are connected to pipes for argon gas outside the vacuum chamber 302. .

In addition, a discharge unit 334 is provided in each film forming chamber 322 . This discharge unit 334 is the same as in the second embodiment (FIG. 8), so detailed description thereof will be omitted here. However, this discharge unit 334 is provided so that the surface to be sputtered of the target made of aluminum faces the outer peripheral surface of the cooling roll 304, and between the target to be sputtered surface and the outer peripheral surface of the cooling roll 304. Just a reminder that the filament is positioned.

According to the winding-type magnetron sputtering apparatus 500 having such a configuration, the sealing film 200 for sealing the organic EL element 120 on the film 400 can be formed as described above.

That is, according to the winding-type magnetron sputtering apparatus 500, the film 400 is conveyed as indicated by the dashed arrow 400a in FIG. At this time, the film 400 is conveyed with the surface on which the organic EL elements, which are the portions to be processed, are arranged faces outward. Then, first, a film forming process for forming an aluminum nitride layer as the first layer 202 is performed in the first film forming chamber 322 . The procedure of the film forming process for forming this aluminum nitride layer is the same as that in the first and second embodiments. Subsequently, a film forming process for forming an aluminum layer as the second layer 204 is performed in the second film forming chamber 322 . The procedure for the film forming process for forming this aluminum layer is also the same as in the first and second embodiments. Further, a film forming process for forming an aluminum nitride layer as the third layer 206 is performed in the third film forming chamber 322, and an aluminum layer as the fourth layer 208 is formed in the fourth film forming chamber 322. A film forming process is performed for the formation. Then, a film forming process for forming an aluminum nitride layer as the fifth layer 210 is performed in the fifth film forming chamber 322 . In this way, the film 400 is passed through each of the film forming chambers 322, 322, .

As described above, according to the winding-type magnetron sputtering apparatus 500 according to the third embodiment, the sealing film 200 can be formed on the film 400, and in particular, the sealing film 200 can be continuously formed. can be done. The sealing film 200 formed by this winding-type magnetron sputtering apparatus 500 is also extremely dense as in the first and second embodiments. Furthermore, although illustration is omitted, although arc discharge plasma 300 is generated in each film forming chamber 322, damage to the film 400, especially damage to the organic EL element 120, caused by the plasma 300 is suppressed. be. As a result, a sealing film 200 that is sufficiently practical for temporary sealing is formed.

In addition, although the structure shown in FIG. 9 was illustrated as this 3rd Example, it is not restricted to this. For example, the transport mechanism 303 has a general configuration and is not limited to the configuration described here.

Moreover, the configuration shown in FIG. 8 according to the second embodiment can also be applied as a winding-type film forming apparatus. In this case, although illustration is omitted, for example, an unwinding roll is provided on the carry-in port 62 side, and a winding roll is provided on the carry-out port 64 side. Then, the film unwound from the unwinding roll is taken up by the take-up roll, so that the film is sequentially conveyed through the film forming chambers 56, 56, . . . . With such a configuration as well, the sealing film 200 can be formed on the elongated film.

[Other application examples]
Each embodiment described above is a specific example of the present invention and does not limit the technical scope of the present invention. The present invention can also be applied to aspects other than these examples.

For example, although the sealing film 200 having a five-layer structure as shown in FIG. 3 was formed in each of the above-described embodiments, the present invention is not limited to this. The number of layers of the sealing film 200 other than five may be formed. In this case, in the first embodiment, the introduction of nitrogen gas into the vacuum chamber 12 is turned on/off according to the number of layers of the sealing film 200 . In the second embodiment, the number of deposition chambers 56 corresponding to the number of layers of the sealing film 200 is provided. Similarly, in the third embodiment, the number of deposition chambers 322 corresponding to the number of layers of the sealing film 200 is provided. However, as described above, it is essential that the first layer 202, which is the bottom layer, is formed of an aluminum nitride layer, which is an insulating material. There are no particular restrictions on the top layer.

Moreover, the sealing film 200 is not limited to the laminated film of the aluminum nitride layer and the aluminum layer, and other kinds of laminated films may be formed. For example, a laminated film of an aluminum nitride layer and an aluminum oxide (AlOx) layer, a laminated film of a silicon nitride (SiNx) layer and a silicon oxide (SiOx) layer, or the like may be formed as the sealing film 200 . However, since oxygen gas is used as a reactive gas when forming an oxide layer such as an aluminum oxide layer or a silicon oxide layer, it is necessary to prevent the filament 20 from being oxidized by the oxygen gas. measures must be taken. In addition, the material of the target 142 is appropriately selected according to the type of laminated film.

Furthermore, the sealing film 200 is not limited to a laminated film of two kinds of layers, and may be a laminated film of three or more kinds of layers. In this case, materials for the reactive gas and the target 142 are appropriately selected according to the types of layers forming the laminated film.

The organic EL element 120 is not limited to the bottom emission type, and may be an element other than the bottom emission type such as the top emission type. The present invention can also be applied to sealing electronic elements other than the organic EL element 120 .

DESCRIPTION OF SYMBOLS 10... Magnetron sputtering apparatus 12... Vacuum chamber 14... Magnetron cathode 18... Sputtering power supply device 20... Filament 22... Cathode power supply device 24... Electric discharge power supply device 30... Control device 32... Gas introduction pipe 34, 36... Piping 36... Nitrogen gas pipe 142 ... target

Claims (9)

A film forming apparatus for forming a sealing film for sealing an electronic element provided on a substrate by a magnetron sputtering method,
a vacuum chamber in which the substrate is accommodated;
a magnetron cathode having a target that is the material of the sealing film and provided in the vacuum chamber so that the surface of the target to be sputtered faces the electronic element on the substrate;
discharge gas introducing means for introducing a discharge gas into the vacuum chamber;
Sputtering power supply means for discharging the discharge gas and generating plasma in the vacuum chamber by supplying sputtering power to the vacuum chamber and the magnetron cathode using the vacuum chamber as an anode and the magnetron cathode as a cathode;
reactive gas introducing means for introducing a reactive gas, which is another material of the sealing film, into the vacuum chamber;
a filament that is provided between the substrate and the surface to be sputtered and is heated by being supplied with thermionic emission power to emit thermionic electrons;
Discharge power supply means for accelerating the thermoelectrons and inducing arc discharge around the filament by supplying discharge power to the vacuum chamber and the filament with the vacuum chamber as the anode and the filament as the cathode; and control means for controlling at least the reactive gas introduction means so as to form a laminated film in which a plurality of films of different types are laminated as the sealing film ,
The film forming apparatus , wherein a sputtering current, which is a current component of the sputtering power, is 1.5 A or more and 8 A or less . The control means controls the reactive gas introducing means so that the laminated film in which a film containing the reactive gas component and a film not containing the reactive gas component are laminated as the sealing film is formed. 2. The film forming apparatus according to claim 1, wherein introduction of said reactive gas into said vacuum chamber by is turned on/off. A film forming apparatus for forming a sealing film for sealing an electronic element provided on a substrate by a magnetron sputtering method,
A vacuum chamber having a plurality of film formation chambers for individually forming a plurality of films of different types that constitute the sealing film, and a laminated film in which the plurality of films are laminated is formed as the sealing film. a housing means for sequentially housing the substrates in the plurality of film formation chambers,
For each film forming chamber,
a magnetron cathode having a target that is a material of the sealing film and provided in the deposition chamber so that a sputtered surface of the target faces the electronic element on the substrate;
discharge gas introducing means for introducing a discharge gas into the film forming chamber;
Sputtering power supply for discharging the discharge gas and generating plasma in the film forming chamber by supplying sputtering power to the film forming chamber and the magnetron cathode using the film forming chamber as an anode and the magnetron cathode as a cathode. means,
a filament which is provided between the substrate and the surface to be sputtered and is heated by being supplied with thermionic emission power to emit thermionic electrons; and a film forming process using the film forming chamber as an anode and the filament as a cathode Discharge power supply means for accelerating the thermal electrons and inducing arc discharge around the filament by supplying discharge power to the chamber and the filament, and a part of the film formation chamber, a reactive gas introducing means for introducing a reactive gas, which is another material of the sealing film, into the film formation chamber ;
The film forming apparatus , wherein a sputtering current, which is a current component of the sputtering power, is 1.5 A or more and 8 A or less . The plurality of film formation chambers are provided so as to be continuous with each other,
4. The film forming apparatus according to claim 3, wherein said accommodating means includes a conveying means for conveying said substrate so that said substrate sequentially passes through said plurality of film forming chambers. The substrate is elongated,
5. The film forming apparatus according to claim 4, wherein said transport means transports said long substrate along the longitudinal direction of said substrate. 6. The film forming apparatus according to claim 1, wherein said electronic element includes an organic electroluminescence element. The target is made of aluminum,
7. The film forming apparatus according to claim 1, wherein said reactive gas includes nitrogen gas. A film formation method for forming a sealing film for sealing an electronic element provided on a substrate by a magnetron sputtering method, comprising:
A discharge gas introduction step of introducing a discharge gas into a vacuum chamber in a state in which a target to be sputtered of a magnetron cathode having a target that is a material of the sealing film is directed toward the electronic element on the substrate. ,
A sputtering power supply step of discharging the discharge gas and generating plasma in the vacuum chamber by supplying sputtering power to the vacuum chamber and the magnetron cathode using the vacuum chamber as an anode and the magnetron cathode as a cathode;
a reactive gas introducing step of introducing a reactive gas, which is another material of the sealing film, into the vacuum chamber;
a thermionic emission step of supplying thermoelectron emission power to a filament provided between the substrate and the surface to be sputtered to heat the filament and emit thermoelectrons from the filament;
A discharge power supply step of accelerating the thermoelectrons and inducing an arc discharge around the filament by supplying discharge power to the vacuum chamber and the filament with the vacuum chamber as the anode and the filament as the cathode; and a control step of controlling the introduction mode of the reactive gas at least in the reactive gas introduction step so as to form a laminated film in which a plurality of films of different types are laminated as the sealing film ,
The film formation method , wherein a sputtering current, which is a current component of the sputtering power, is 1.5 A or more and 8 A or less . A film formation method for forming a sealing film for sealing an electronic element provided on a substrate by a magnetron sputtering method, comprising:
A vacuum chamber having a plurality of film formation chambers for individually forming the plurality of films so that a laminated film in which a plurality of films of different types are laminated as the sealing film is formed. including a housing step of sequentially housing the substrates in the film chamber;
For each film forming chamber,
A discharge gas introduction for introducing a discharge gas into the film formation chamber in a state in which a sputtered surface of the target of a magnetron cathode having a target that is a material of the sealing film is directed toward the electronic element on the substrate. step,
Sputtering power supply for discharging the discharge gas and generating plasma in the film forming chamber by supplying sputtering power to the film forming chamber and the magnetron cathode using the film forming chamber as an anode and the magnetron cathode as a cathode. step,
a thermionic emission step of supplying a thermionic emission power to a filament provided between the substrate and the surface to be sputtered to heat the filament and emit thermionic electrons from the filament; and and the filament as a cathode to supply discharge power to the film-forming chamber and the filament, thereby accelerating the thermoelectrons and inducing an arc discharge around the filament. Further, in some of the film formation chambers, a reactive gas introducing step of introducing a reactive gas, which is another material of the sealing film, into the film formation chambers ,
The film formation method , wherein a sputtering current, which is a current component of the sputtering power, is 1.5 A or more and 8 A or less .

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