Film deposition device, film deposition method, and method for manufacturing electronic device

Abstract

To provide a film deposition device capable of depositing a film on a film deposition object by sputtering using a rotary target made of an alloy of 2 or more components.SOLUTION: A film deposition device has: a cylindrical target made of an alloy of 2 or more components; and magnetic field generation means of creating a leakage magnetic field leaked from an outer periphery surface of the target while an angle around a rotation shaft parallel to a cylindrical center axial line is variably provided inside the target, and deposits an alloy thin film on a film deposition object arranged opposite to the target while rotating the target by sputtering. An angle of the magnetic field generation means is controlled based on information of a composition ratio of the alloy thin film.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present invention relates to a film formation apparatus and a film formation method for forming a film on a substrate by sputtering, and a method for manufacturing an electronic device. [Background technology]

[0002] As a deposition device for depositing a thin film of metal or metal oxide on a deposition target such as a substrate, there is a sputtering device that places a cylindrical target (hereinafter, referred to as a rotary target) facing a substrate and performs sputtering while rotating the rotary target. A sputtering device that uses a rotary target has the advantage that the surface of the target can be sputtered more uniformly than a planar sputtering device that uses a flat target. There is also a magnetron sputtering type sputtering device that arranges a magnet inside the rotary target and forms a magnetic field that leaks out of the rotary target, thereby increasing the plasma density near the surface of the rotary target (Patent Document 1).

[0003] An example of a thin film that can be formed by a sputtering device is a cathode metal film formed on an organic layer of an organic EL (electroluminescent) element. As a component of the cathode metal film, from the viewpoint of electron injection into the organic layer, alkali metals, alkaline earth metals, or alloys thereof having a low work function such as Mg are preferable, but from the viewpoint of oxidation resistance, metals having a high work function such as Au, Ag, and Al are preferable. In order to achieve both electron injection and oxidation resistance, there is a cathode metal film formed of an alloy mainly composed of Mg and Ag (Patent Document 2). In Patent Document 2, two targets, a flat target made of Mg and a flat target made of Ag, are placed in a chamber, and a voltage is applied to both targets simultaneously to perform sputtering, thereby forming a layer made of Mg-Ag alloy on the organic layer, and then a voltage is applied only to the Ag target to perform sputtering, thereby forming a layer made of Ag on the Mg-Ag alloy layer, thereby forming a cathode metal film made of a multilayer film with a difference in the composition ratio of Mg and Ag in the thickness direction.

[0004] Patent Document 3 describes a method for producing a rotary target made of an Mg-Ag alloy. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-200520 A [Patent Document 2] JP 2004-200047 A [Patent Document 3] JP 2013-204052 A Summary of the Invention [Problem to be solved by the invention]

[0006] The sputtering device in Patent Document 2 uses multiple independent flat targets made of each alloy component, and does not describe a sputtering device using a rotary target made of an alloy. Patent Document 3 describes a rotary target made of a two-component alloy, but does not describe a sputtering device using it.

[0007] An object of the present invention is to provide a film formation apparatus capable of forming a film on a film formation target by sputtering using a rotary target made of an alloy of two or more components. [Means for solving the problem]

[0008] The present invention includes a cylindrical target made of an alloy of two or more components, a magnetic field generating means provided inside the target such that an angle around a rotation axis parallel to the central axis of the cylindrical shape can be changed, the magnetic field generating means generating a leakage magnetic field leaking from an outer peripheral surface of the target; having A film formation apparatus for forming an alloy thin film by sputtering on a film formation target disposed opposite the target while rotating the target, The film forming apparatus is characterized in that the angle of the magnetic field generating means is controlled based on information on the composition ratio of the alloy thin film.

[0009] The present invention includes a cylindrical target made of an alloy of two or more components, a magnetic field generating means provided inside the target such that an angle around a rotation axis parallel to the central axis of the cylindrical shape can be changed, the magnetic field generating means generating a leakage magnetic field leaking from an outer peripheral surface of the target; A film forming method using a film forming apparatus having the following features: forming an alloy thin film by sputtering on a film-forming object disposed opposite the target while rotating the target; controlling an angle of the magnetic field generating means based on information on the composition ratio of the alloy thin film; The film forming method is characterized by having the following features. Effect of the Invention

[0010] According to the present invention, it is possible to provide a film formation apparatus capable of forming a film on a film formation target by sputtering using a rotary target made of an alloy of two or more components. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing the configuration of an organic EL element according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an in-line type film forming apparatus according to an embodiment. [Diagram 3] FIG. 2 is a diagram showing a cluster type film forming apparatus according to an embodiment. [Figure 4] FIG. 2 is a schematic diagram showing the configuration of a substrate transport type sputtering apparatus according to an embodiment. [Diagram 5] FIG. 2 is a schematic diagram showing the configuration of a substrate transport type sputtering apparatus according to an embodiment. [Figure 6] FIG. 2 is a schematic diagram showing the configuration of a magnet unit of the sputtering apparatus of the embodiment. [Figure 7] FIG. 4 is a diagram for explaining the angle of a magnet unit of the sputtering apparatus of the embodiment. [Figure 8]FIG. 2 is a schematic diagram showing the configuration of a rotating cathode unit moving type sputtering apparatus according to an embodiment. [Figure 9] FIG. 2 is a schematic diagram showing the configuration of a twin cathode type sputtering apparatus according to the embodiment. [Figure 10] FIG. 2 is a schematic diagram showing the configuration of a twin cathode type sputtering apparatus according to the embodiment. [Figure 11] FIG. 4 is a diagram showing the angle of a magnet unit of a twin cathode type sputtering apparatus according to an embodiment. [Figure 12] FIG. 4 is a diagram showing the angle of a magnet unit of a twin cathode type sputtering apparatus according to an embodiment. [Figure 13] 5A to 5C are diagrams showing the swinging operation of the magnet unit of the sputtering apparatus of the embodiment. [Figure 14] FIG. 4 is a diagram showing the relationship between the angle of the magnet unit of the sputtering device of the embodiment and the Mg composition ratio. [Figure 15] FIG. 4 is a diagram showing the difference in deposition amount depending on the alloy components in the sputtering apparatus of the embodiment. [Figure 16] FIG. 11 is a graph showing the relationship between the sputtering deposition time and the Mg composition ratio in Example 2. [Figure 17] FIG. 11 is a graph showing the relationship between the sputtering deposition time and the Mg composition ratio in Example 3. [Figure 18] FIG. 13 is a diagram showing a device region and an inspection region in a substrate according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The following describes in detail the embodiments of the present invention. However, the following embodiments merely exemplify preferred configurations of the present invention, and the scope of the present invention is not limited to these configurations. Furthermore, unless otherwise specified, the hardware and software configurations, process flow, manufacturing conditions, dimensions, materials, shapes, etc. of the device in the following description are not intended to limit the scope of the present invention to these alone. Although the embodiments describe a number of features, the combination of these features may be used in various ways. Not all of the features are essential to the invention, and a plurality of features may be combined in any desired manner. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant descriptions are omitted.

[0013] The film forming apparatus according to the present invention is used to deposit and form a thin film on a substrate (including a substrate on which a laminate is formed) in the manufacture of various electronic devices such as semiconductor devices, magnetic devices, and electronic components, and optical components. More specifically, the film forming apparatus according to the present invention is preferably used in the manufacture of electronic devices such as light-emitting elements, photoelectric conversion elements, and touch panels. In particular, it is particularly preferably applicable in the manufacture of organic light-emitting elements such as OLEDs (Organic Light Emitting Diodes), and organic photoelectric conversion elements such as organic thin-film solar cells. The electronic device in the present invention also includes a display device (e.g., an organic EL (Electro-Luminescence) display device) and a lighting device (e.g., an organic EL lighting device) equipped with a light-emitting element, and a sensor (e.g., an organic CMOS image sensor) equipped with a photoelectric conversion element. In addition, the present invention also includes a manufacturing method of an electronic device having a step of forming a thin film on a substrate using a film forming apparatus according to each of the following embodiments or a film forming apparatus obtained by modifying the film forming apparatus of each embodiment within the scope of the present invention.

[0014] FIG. 1 is a schematic diagram showing a typical layer structure of an organic EL element that can be manufactured using the film forming apparatus of the following embodiment. An OLED generally has a structure in which an anode 61, an organic light-emitting layer 62, and a cathode 65 are laminated on a substrate 6. The film forming apparatus according to the present invention is preferably used when forming a cathode 65 on the organic light-emitting layer 62. The cathode 65 is an alloy thin film made of two-component metal materials. The first component of the alloy constituting the cathode 65 is an alkali metal, an alkaline earth metal, or an alloy thereof having a low work function such as Mg from the viewpoint of electron injection into the organic light-emitting layer 62, and the second component is a metal having a high work function such as Au, Ag, or Al from the viewpoint of oxidation resistance. In the following embodiment, the first component is Mg, and the second component is Ag.

[0015] The cathode 65 is preferably configured as a multilayer film consisting of a first layer 63 and a second layer 64 formed on the first layer 63. This is because it is preferable to increase the Mg composition ratio on the side closer to the organic light-emitting layer 62 to increase the electron injection property, while it is preferable to increase the Ag composition ratio on the side closer to the external environment to increase the oxidation resistance. By forming the cathode 65 as a multilayer film having different composition ratios, it is possible to achieve both electron injection property and oxidation resistance. Thus, the first layer 63 and the second layer 64 are both Mg-Ag alloys, but the Mg composition ratio of the first layer 63 is made higher than that of the second layer 64, and the Ag composition ratio of the second layer 64 is made higher than that of the first layer 63. That is, the cathode 65 is configured as a multilayer film having different alloy composition ratios (having a gradient in the composition ratio) in the film thickness direction.

[0016] The alloy constituting the cathode 65 is not limited to this example, and may be another alloy mainly composed of a first component having excellent electron injection properties and a second component having excellent oxidation resistance. Examples of the first component include Li, Na, Mg, K, Ca, Cs, and Yb. Examples of the second component include Ag and Al.

[0017] The film forming apparatus of the present invention is not limited to the formation of a cathode for an OLED or a multilayer film having different alloy composition ratios in the thickness direction, but can be generally applied to the formation of a film made of an alloy of two or more components. In particular, the present invention is not limited to the formation of a cathode made of a multilayer film, but can also be applied to the formation of a cathode made of a single-layer alloy thin film. The film forming apparatus of the present invention is not limited to the formation of a film on an organic film, but can form a film on various surfaces as long as it is a combination of materials that can be formed by sputtering, such as metal materials and oxide materials.

[0018] The present invention is applicable to both an in-line type film forming apparatus as shown in FIG. 2 and a cluster type film forming apparatus as shown in FIG.

[0019] FIG. 2 is a schematic diagram showing a part of an in-line type film forming apparatus 100 in which a plurality of film forming chambers are connected. The film forming apparatus 100 has film forming chambers 101, 102, 103, and 104, and has an inspection chamber 105 at the rear of the film forming chamber 104. In each film forming chamber, an anode 61, an organic light emitting layer 62, a first layer 63 of a cathode 65, and a second layer 64 of a cathode 65 are formed. The substrate 6 on which the film is formed in the film forming chamber 104 is carried into the inspection chamber 105 at the rear. An inspection device (e.g., EPMA (electron probe microanalyzer)) capable of measuring the Mg composition ratio of the alloy thin film is installed in the inspection chamber 105, and composition analysis can be performed on the substrate 6 on which the Mg-Ag alloy thin film is formed in the film forming chamber 104. Note that both the first layer 63 and the second layer 64 constituting the cathode 65 may be formed in one film forming chamber.

[0020] 3 is a schematic diagram showing a part of a cluster-type film formation apparatus 111 in which a plurality of vacuum chambers are connected. In this film formation apparatus 111, a first cluster C1, a second cluster C2, and a third cluster C3 are connected in series. In addition to the film formation chambers 101 to 104, each cluster has a known chamber such as a mask stocker as appropriate, but the description thereof will be omitted here. An inspection chamber 105 is provided between the second cluster C2 and the third cluster C3. A composition analysis is performed in the inspection chamber 105 on the alloy thin film formed in the second cluster C2.

[0021] Each deposition chamber is provided with a device for depositing a film by sputtering or vapor deposition. An example in which a sputtering device is provided will be described below.

[0022] (Substrate transport type sputtering device) An example of a sputtering apparatus to which the present invention can be applied will be described with reference to Fig. 4. In the following description, the direction parallel to the transport direction S of the substrate 6 transported within the sputtering apparatus 1 is defined as the X direction, the direction parallel to the rotation axis of the cylindrical target 2 provided in the sputtering apparatus 1 is defined as the Y direction, and the vertical upward direction is defined as the Z direction. Fig. 4 is a diagram showing a schematic internal configuration of the sputtering apparatus 1 as viewed from the Y direction.

[0023] The sputtering apparatus 1 shown in Fig. 4 has a chamber 10 in which a substrate 6 and a target 2, which are objects to be deposited, are disposed. In the sputtering apparatus 1, the target 2 is disposed vertically below the substrate 6, and deposition is performed by depositing up with the deposition surface of the substrate 6 facing vertically downward. Note that the present invention is not limited to this, and may be configured such that the target 2 is disposed vertically above the substrate 6, and deposition is performed by depositing down with the deposition surface of the substrate 6 facing vertically upward. Alternatively, the substrate 6 may be set up vertically, and deposition may be performed with the deposition surface of the substrate 6 parallel to the vertical direction.

[0024] The rotating cathode unit 8 has the target 2, which is a cylindrical rotary target, and a magnet unit 3, which is disposed in the hollow inside the target 2 and serves as a magnetic field generating means for generating a magnetic field around the outer periphery of the target 2. A backing tube 2a is provided inside the target 2. The rotating cathode unit 8 is fixed to a chamber 10, and the target 2 is supported by the chamber 10 so as to be rotatable around the central axis of the cylinder. The target 2 rotates in the direction of arrow R by the driving force of a target drive device 11 being transmitted by a drive transmission means such as a gear. The arrow R is the clockwise direction in a cross section perpendicular to the Y direction shown in FIG. 4.

[0025] The target 2 is made of a film-forming material for forming a film on the substrate 6 by sputtering, and functions as a supply source of the film-forming material. Here, an example will be described in which a cathode 65 (upper electrode) made of an Mg-Ag alloy is formed by sputtering on the substrate 6 on which the OLED anode 61 and organic light-emitting layer 62 shown in Fig. 1 are already formed. Therefore, the material constituting the target 2 is a two-component alloy of Ag and Mg.

[0026] A layer formed of the film-forming material of the target 2 is formed on the outside of the backing tube 2a. The backing tube 2a is connected to a power source 13 and functions as a cathode to which a negative voltage is applied from the power source 13. The voltage may be applied directly to the target 2, in which case the backing tube 2a may not be provided. The power source 13 may be a DC power source, an AC power source, or a high-frequency power source depending on the material of the target 2. The chamber 10 is grounded. The target 2 is a cylindrical target, but the term "cylindrical" does not mean only a mathematically strict cylindrical target, but also includes a target whose generatrix is ​​not a straight line but a curved line, and a target whose cross section perpendicular to the central axis is not a mathematically strict "circle". In other words, the target 2 in the present invention may be a cylindrical target that can rotate around the central axis.

[0027] The magnet unit 3 forms a magnetic field on a part of the surface side of the target 2. The magnet unit 3 is provided inside the target 2 such that the angle around a central axis parallel to the central axis of the cylindrical shape of the target 2 can be changed. The magnet unit 3 is supported so as to be rotatable about the central axis. The magnet unit 3 rotates in a clockwise and counterclockwise direction in a cross section perpendicular to the Y direction shown in FIG. 4 as indicated by the arrow M, as the driving force of the magnet driving device 110 is transmitted by a drive transmission means such as a gear. The magnet unit 3 can be stationary at any angle. The rotation of the target 2 by the target driving device 11 and the rotation of the magnet unit 3 by the magnet driving device 110 are controlled independently.

[0028] The substrate 6 is carried in through one gate valve 17 provided on a side wall of the chamber 10. A film is formed on the substrate 6 by sputtering while the substrate 6 is transported horizontally (in the direction indicated by the arrow S) within the chamber 10 by the transport member 120. After a film is formed on the entire film-forming target surface of the substrate 6, the substrate 6 is carried out through a gate valve 18 provided on the other side wall of the chamber 10.

[0029] Gas introduction means 16 and exhaust means 15 are connected to chamber 10, and the pressure inside can be adjusted to a predetermined pressure. A sputtering gas (an inert gas such as argon or a reactive gas such as oxygen or nitrogen) is introduced into chamber 10 by gas introduction means 16 through an inlet 41 provided in chamber 10. Air is exhausted from the inside of chamber 10 through exhaust port 5 by exhaust means 15 such as a vacuum pump. In this way, the pressure inside chamber 10 is adjusted to a predetermined pressure.

[0030] The gas introduction means 16 has an inlet 41 and is composed of a supply source such as a gas cylinder (not shown), a piping system connecting the supply source and the inlet 41, and various vacuum valves, mass flow controllers, etc. provided in the piping system, and the supply amount can be adjusted by a flow control valve of the mass flow controller. The flow control valve has an electrically controllable configuration such as an electromagnetic valve. The inlet 41 is disposed on a vertical side wall of the chamber 10. The installation position of the inlet 41 is not limited to the side wall, and may be provided on the bottom wall or the ceiling wall. Also, the piping may extend into the chamber 10, and the inlet may open into the chamber 10. Also, a configuration in which a plurality of inlets 41 are provided and arranged along the rotation axis direction of the target 2 may be adopted.

[0031] The exhaust means 15 has a vacuum pump and a piping system connecting the vacuum pump and the exhaust port 5. The piping system is provided with an electrically controllable flow control valve such as a conductance valve, and the exhaust amount can be adjusted by the control valve. The exhaust port 5 is provided in the bottom wall of the chamber 10. The installation position of the exhaust port 5 is not limited to the bottom wall, and it may be provided in a vertical side wall or a ceiling wall. Also, the piping may extend into the chamber 10, and the exhaust port 5 may open into the chamber 10.

[0032] The control unit 14 controls the target driving device 11 while keeping the angle of the magnet unit 3 fixed. The target 2 is driven and rotated in the direction of arrow R by the magnet unit 3, and a negative voltage is applied to the target 2 by controlling the power supply 13. When a voltage is applied to the target 2, the region where the magnetic field generated by the magnet unit 3 exists becomes a sputtering region A where plasma is concentrated and sputtered particles are generated. Since the magnet unit 3 is stationary with respect to the chamber 10 during the film formation process, the opposing angle between the sputtering region A and the film formation target surface of the substrate 6 is constant during the film formation process. Positive ionized inert gas ions in the plasma collide with the surface of the target 2, and atoms and molecules of the material constituting the target 2 are knocked out and released from the target 2. The particles of the film formation material released from the target 2 adhere to and accumulate on the film formation target surface of the substrate 6.

[0033] Here, the opposing angle between the sputtering region A and the film-forming surface of the substrate 6 is defined as, for example, the angle between a line segment that bisects the central angle of an arc corresponding to the sputtering region A on the cylindrical surface of the target 2 and a virtual plane including the film-forming surface of the substrate 6, within a virtual plane perpendicular to the rotation axis of the target 2.

[0034] As the substrate 6 is moved in the horizontal direction (indicated by the arrow S) by the transport member 120, the film formation target area of ​​the substrate 6 facing the sputtering area A moves in the horizontal direction. As a result, a film is formed on the film formation target surface of the substrate 6 sequentially from the downstream end to the upstream end in the transport direction S. As a result, the sputtering film is formed uniformly over the entire surface of the substrate 6.

[0035] The area on the surface of the target 2 from which the sputtered particles are emitted moves in the circumferential direction as the target 2 rotates. Therefore, when focusing on a certain local area on the surface of the target 2, sputtering occurs intermittently at a period determined by the rotation speed of the target 2.

[0036] 5 is a diagram showing a schematic diagram of the internal configuration of the sputtering apparatus 1 as viewed from the X direction. The Y direction end of the target 2 is rotatably supported by a support block 210 and an end block 220. The support block 210 and the end block 220 are provided with a power transmission mechanism that transmits a driving force from a target driver 11, which is a rotation driver, to the target 2. The target driver 11 has a drive source such as a motor, and drives the target 2 to rotate via the power transmission mechanism.

[0037] FIG. 6 is a diagram showing a schematic configuration of the magnet unit 3 provided inside the target 2. The magnet unit 3 includes a central magnet 31 extending in a direction parallel to the rotation axis of the target 2, a peripheral magnet 32 ​​surrounding the central magnet 31 and having a polarity different from that of the central magnet 31, and a yoke plate 33. The peripheral magnet 32 ​​is composed of a pair of straight portions 32a and 32b extending in parallel to the central magnet 31, and turning portions 32c and 32d connecting both ends of the straight portions 32a and 32b. The magnetic field formed by the magnet unit 3 has magnetic field lines that loop back from the magnetic pole of the central magnet 31 toward the straight portions 32a and 32b of the peripheral magnet 32. As a result, a toroidal magnetic field tunnel extending in the direction of the rotation axis of the target 2 is formed near the surface of the target 2. This magnetic field captures electrons, concentrating plasma near the surface of the target 2, and increasing the efficiency of sputtering. The magnetic field of the magnet unit 3 generates high-density plasma, and the region where sputtered particles are generated intensively is defined as a sputtering region A.

[0038] The magnet unit 3 is fixed on a pedestal 34, and a rotation shaft 35 is fixed to the pedestal 34. The rotation shaft 35 extends parallel to the central axis of the cylindrical target 2, rotatably supports the pedestal 34 with respect to the chamber 10, and rotates by the driving force of the magnet driving device 110. As a result, the magnet unit 3 is supported rotatably about the central axis, and the target The angle around the rotation axis 35 parallel to the central axis of the cylindrical shape of the magnet unit 2 is variable. The rotational movement of the magnet unit 3 is performed by the driving force of the magnet driving device 110. The magnet driving device 110 is configured to rotate the magnet unit 3 to an arbitrary angle and to stop it at that angle. This makes it possible to perform operations such as performing sputtering with the magnet unit 3 stationary during the film formation process, oscillating the magnet unit 3 during the film formation process as described below, and changing the angle of the magnet unit 3 to control the composition ratio when the film formation process is not being performed. In the sputtering device 1, an example has been described in which the central axis of the rotation axis 35 coincides with the central axis of the target 2, but the central axis of the rotation axis 35 may be parallel to the central axis of the target 2. The driving force of the magnet driving device 110 is transmitted to the rotation axis 35 via a power transmission mechanism (not shown). The magnet driving device 110 has a driving source such as a motor.

[0039] FIG. 7 shows the positional relationship between a substrate 6, a target 2, and a magnet unit 3 when a film is formed by sputtering up on a surface vertically below a substrate 6 placed above the target 2 using a cylindrical target 2.

[0040] Sputtering gas ions (e.g., Ar) generated by applying a negative voltage to the target 2 + ) collide with the surface of the target 2, atoms and molecules of the film-forming material that constitutes the target 2 are emitted as sputtered particles from the target 2. The location and direction in which these emitted materials (sputtered particles) are emitted from the surface of the target 2 during sputtering can be set by the magnetic field formed in the vicinity of the surface of the target 2 by the magnet unit 3.

[0041] In FIG. 7, the rotation center O of the target 2 and the rotation center of the rotation axis 35 of the magnet unit 3 coincide with each other. Sputtered particles are generated intensively in a sputtering region A defined by the positions of line segments D2 and D3 passing through the rotation center of the rotation axis 35 of the magnet unit 3 and the position between the central magnet 31 and the peripheral magnet 32. The sputtering region A may be a region determined based on the magnetic flux distribution of the magnetic field formed by the magnet unit 3. It may also be a region on the surface of the target 2 where the magnetic field strength has a certain value or more. It may also be determined based on the arrangement and structure of the magnets of the magnet unit 3, the position where sputtered particles are generated intensively, and phenomena generally, statistically, empirically, and experimentally observed as the direction in which substances emitted from the surface of the target 2 are emitted during sputtering.

[0042] The angle θ of the line segment D1 passing through the center of rotation of the rotation shaft 35 of the magnet unit 3 and the center of the sputtering region A is defined as the angle of the magnet unit 3. The angle θ of the magnet unit 3 is an angle based on the position where the line segment D1 is perpendicular to the film formation target surface of the substrate 6 (when the magnet unit 3 is located at the position shown by the dashed line in FIG. 7), and the clockwise direction in FIG. 7 is defined as positive.

[0043] (Moving cathode sputtering device) Another example of a sputtering apparatus to which the present invention can be applied will be described with reference to Fig. 8. Elements common to the above-mentioned substrate conveying type sputtering apparatus will be designated by common names and symbols, and detailed description thereof will be omitted.

[0044] The sputtering apparatus 1X shown in Fig. 8 is a sputtering apparatus in which a substrate 6 is fixed in a chamber 10 and a rotating cathode unit 8X is capable of reciprocating within the chamber 10. Fig. 8 is a diagram showing a schematic diagram of the internal configuration of the sputtering apparatus 1X as viewed from a direction parallel to the rotation axis of a cylindrical target 2 provided in the sputtering apparatus 1X (Y direction).

[0045] In the sputtering apparatus 1 of FIG. 4, the rotating cathode unit 8 does not move relative to the chamber 10, and the substrate 6 moves relative to the chamber 10, so that the substrate 6 is transported from the downstream end of the substrate 6 in the transport direction. 8, a rotating cathode unit 8X moves relative to a chamber 10, while the substrate 6 does not move relative to the chamber 10, and a film is formed on the film-formation target surface of the substrate 6 sequentially from the upstream end in the moving direction of the rotating cathode unit 8X.

[0046] The rotating cathode unit 8X has a moving stage 230, and a partition member 260 disposed around the target 2 is provided on the moving stage 230. The partition member 260 is open in the direction in which the substrate 6 is disposed (vertically upward).

[0047] The movable stage 230 is supported so as to be movable in the horizontal direction (indicated by the arrow T) along a pair of guide rails 250 via a conveying guide such as a linear bearing. The guide rails 250 are provided parallel to the X direction. The movable stage 230 is linearly driven in the X direction by the linear drive device 12. The linear drive device 12 may be any of various known linear motion mechanisms, such as a screw feed mechanism using a ball screw or the like that converts the rotational motion of a rotary motor into linear motion, or a linear motor. Therefore, the rotating cathode unit 8X moves in the X direction within the XY plane, and the target 2 moves in the X direction within the XY plane while rotating around a rotation axis parallel to the Y direction.

[0048] When the substrate 6 is carried into the chamber 10, it is held by a holder 6a vertically above the rotating cathode unit 8X. During the film formation process, the substrate 6 does not move relative to the chamber 10, and the film is formed by sputtering while the rotating cathode unit 8X moves horizontally (in the direction indicated by the arrow T). After the film is formed on the entire film formation target surface of the substrate 6, the substrate 6 is carried out through a gate valve 18 provided on the other side wall of the chamber 10.

[0049] When forming a film by sputtering in the sputtering apparatus 1X, the control unit 14 controls the target driving device 11 to rotate the target 2 in the direction of arrow R, and also controls the power supply 13 to apply a negative voltage to the target 2.

[0050] The rotating cathode unit 8X is moved in the direction of arrow T relative to the chamber 10 by the linear drive device 12, and therefore the sputtering region A moves in the direction of arrow T relative to the chamber 10. Furthermore, the magnet unit 3 does not rotate together with the target 2 during the film formation process, and therefore the opposing angle between the sputtering region A and the film formation target surface of the substrate 6 remains constant during the film formation process. During the film formation process, the substrate 6 is held by the holder 6a and does not move relative to the chamber 10.

[0051] As the rotating cathode unit 8X moves in the horizontal direction by the linear drive device 12, the sputtering region A of the target 2 moves along the film-forming surface of the substrate 6 relative to the chamber 10 together with the movement of the rotating cathode unit 8X. As a result, a film is formed on the film-forming surface of the substrate 6 sequentially from the upstream end to the downstream end in the moving direction T of the rotating cathode unit 8X as the rotating cathode unit 8X moves.

[0052] (Twin cathode type sputtering equipment) Another example of a sputtering apparatus to which the present invention can be applied will be described with reference to Figures 9 and 10. Elements common to the above single cathode type sputtering apparatuses 1 and 1X will be given common names and symbols and detailed descriptions thereof will be omitted.

[0053] Fig. 9 is a diagram showing a schematic internal configuration of the sputtering apparatus 1Y as viewed from a direction parallel to the rotation axis of a cylindrical second target 2R provided in the sputtering apparatus 1Y (Y direction). Fig. 10 is a diagram showing a schematic internal configuration of the sputtering apparatus 1Y as viewed from a direction parallel to the moving direction T of a rotating cathode unit 8Y moving in the sputtering apparatus 1Y (X direction).

[0054] The sputtering apparatus 1Y of FIG. 9 is similar to the sputtering apparatus 1X of FIG. The rotating cathode unit 8Y moves, while the substrate 6 does not move relative to the chamber 10, and a film is formed on the film formation target surface of the substrate 6, successively from the end on the upstream side in the movement direction of the rotating cathode unit 8Y.

[0055] The rotating cathode unit 8 of the sputtering apparatus 1 in Figure 4 was composed of a cylindrical target 2 and a magnet unit 3, while the rotating cathode unit 8Y of the sputtering apparatus 1Y in Figure 9 is composed of a cylindrical first target 2L, a first magnet unit 3L which is a first magnetic field generating means provided inside the first target 2L with an angle around a rotation axis parallel to the central axis of the cylinder and which generates a leakage magnetic field leaking from the outer peripheral surface of the first target 2L, a cylindrical second target 2R, and a second magnet unit 3R which is a second magnetic field generating means provided inside the second target 2R with an angle around a rotation axis parallel to the central axis of the cylinder and which generates a leakage magnetic field leaking from the outer peripheral surface of the second target 2R. The configurations of the first target 2L and the first magnet unit 3L, and the configurations of the second target 2R and the second magnet unit 3R are similar to those of the target 2 and the magnet unit 3 of the sputtering apparatus 1 in Fig. 4, but the rotation directions of the first target 2L and the second target 2R by the target driving device 11Y are opposite to each other. The first target 2L rotates in the direction of arrow L, and the second target 2R rotates in the direction of arrow R opposite to the direction of arrow L. The first magnet unit 3L and the second magnet unit 3R rotate as shown by arrows ML and MR by the driving force of the magnet driving device 110Y.

[0056] The configuration in which the rotating cathode unit 8Y can move within the chamber 10 is the same as that of the sputtering apparatus 1X in FIG. 8. The rotating cathode unit 8Y has a moving stage 230, and a support block 210 and an end block 220 that rotatably support the first target 2L and the second target 2R. On the moving stage 230, the first target 2L and the second target 2R are arranged side by side in the moving direction T (parallel to the X direction) of the rotating cathode unit 8Y. The moving stage 230 is provided with a partition member 260 arranged to surround the first target 2L and the second target 2R. Note that in FIG. 10, the partition member 260 is omitted to avoid complication. The partition member 260 opens in the direction in which the substrate 6 is arranged (vertically upward).

[0057] When forming a film by sputtering in the sputtering apparatus 1Y, the control unit 14 controls the target driving device 11Y to rotate the first target 2L and the second target 2R in the directions of the arrows L and R, respectively, and controls the power supply 13 to apply a negative voltage to the first target 2L and the second target 2R. The manner of forming a film by sputtering is the same as that of the sputtering apparatus 1X in FIG.

[0058] FIG. 11 is a diagram showing the positional relationship of the first magnet unit 3L, the second magnet unit 3R, the first target 2L, the second target 2R, and the substrate 6 of the sputtering apparatus 1Y of FIG. 9. In FIG. 11, the rotation center O of the first target 2L and the rotation center of the rotation axis 35L of the first magnet unit 3L coincide with each other. Sputter particles are generated intensively in a sputtering region AL defined by the positions of the line segments D2L and D3L passing through the rotation center of the rotation axis 35L of the first magnet unit 3L and the position between the central magnet 31L and the peripheral magnet 32L. In addition, the rotation center O of the second target 2R and the rotation center of the rotation axis 35R of the second magnet unit 3R coincide with each other. Sputter particles are generated intensively in a sputtering region AR defined by the positions of the line segments D2R and D3R passing through the rotation center of the rotation axis 35R of the second magnet unit 3R and the position between the central magnet 31R and the peripheral magnet 32R.

[0059] The angle θL of the line segment D1L passing through the center of rotation of the rotation shaft 35L of the first magnet unit 3L and the center of the sputtering area AL is defined as the angle of the first magnet unit 3L. The angle θR of the line segment D1R passing through the center of rotation of the rotation shaft 35R of the second magnet unit 3R and the center of the sputtering area AR is defined as the angle of the second magnet unit 3R. The angles θL and θR of R are angles based on the position where the line segments D1L and D1R are perpendicular to the film-forming surface of the substrate 6 (when the first magnet unit 3L and the second magnet unit 3R are located at the positions shown by the dashed lines in Figure 11), and the clockwise direction in Figure 11 is considered positive.

[0060] The first target 2L and the second target 2R are made of an Mg-Ag alloy of the same composition, and the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R are equal. That is, the line segment D1L of the first magnet unit 3L and the line segment D1R of the second magnet unit 3R face in the same direction.

[0061] 12, the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R may be set to have the same absolute value and opposite signs. In this case, the line segment D1L of the first magnet unit 3L and the line segment D1R of the second magnet unit 3R are oriented symmetrically with respect to the movement direction T (X direction) of the rotating cathode unit 8Y.

[0062] The outer diameter of the first target 2L and the second target 2R was 140 mm, and the distance between the centers of the first target 2L and the second target 2R was 300 mm.

[0063] It should be noted that the twin cathode type sputtering apparatus 1Y in Figure 9 is configured to have two cathodes in a rotating cathode unit moving type sputtering apparatus, but the present invention can also be applied to a twin cathode type sputtering apparatus having two cathodes in a substrate transport type sputtering apparatus such as the sputtering apparatus 1 in Figure 4.

[0064] (Magnet unit swing type sputtering device) Another example of a sputtering apparatus to which the present invention can be applied will be described with reference to Fig. 13. Elements common to the above single cathode type sputtering apparatus 1 will be given common names and symbols and detailed description will be omitted.

[0065] 4, an example is shown in which the angle θ of the magnet unit 3 is adjusted before the start of film formation, and the magnet unit 3 is stationary at the adjusted angle θ during the film formation process. In contrast, the magnet unit 3 may be swung within a small angle range forward and backward from the adjusted angle θ during the film formation process.

[0066] FIG. 13 is a diagram showing the operation when the magnet unit 3 is swung. In FIG. 13, the magnet unit 3 shown by the solid line is at a position of angle θ determined before the start of film formation, as shown by the line segment D1. As shown by the dashed line, during the film formation process, the magnet unit 3 continues to move so as to swung between a first position shown by the line segment D11 and a second position shown by the line segment D12 within a range of angle δ centered on the position of angle θ. That is, during the film formation process, the line segment D1 of the magnet unit 3 swung in a range of θ-δ / 2 degrees to θ+δ / 2 degrees. This makes it possible to uniformize deposition unevenness caused by the shapes and arrangement of magnets such as the central magnet 31 and the peripheral magnets 32 that constitute the magnet unit 3.

[0067] As described later, since the angle θ of the magnet unit 3 affects the composition ratio of the alloy thin film to be formed, it is preferable that the angle δ of the oscillation range is small. For example, the oscillation range is set to within ±5 degrees around the initial angle θ. In this case, the magnet unit 3 oscillates in the range of θ-5 degrees to θ+5 degrees during the film formation process.

[0068] (Relationship between Mg composition ratio and angle of magnet unit) Next, control of the Mg composition ratio by adjusting the angle of the magnet unit, which is a feature of the present invention, will be described.

[0069] In this example, a cylindrical sputtering target made of an alloy material of Ag and Mg was used as the target 2. The composition ratio of Mg in the Mg-Ag alloy target was approximately 10 vol.%.

[0070] The manufacturing method of the target 2 will be described. After melting and alloying Ag with a purity of 99.9% or more and Mg with a purity of 99.9% or more, the molten metal was dropped from the bottom of a crucible and an inert gas such as argon was sprayed onto it to produce atomized Mg-Ag alloy powder. The particle size of the atomized powder was set to 1 μm or more and 1000 μm or less. The atomized powder was sprayed onto a backing tube 2a together with a high-velocity inert gas to produce a cylindrical target 2 made of Mg-Ag alloy. The backing tube 2a can be made of stainless steel (SUS304, SUS630, etc.), titanium, etc.

[0071] In this embodiment, an Mg-Ag alloy target is used, but an alloy or compound containing Cu, Al, Ti, Mo, Cr, Ag, Au, Ni, etc. may be used depending on the purpose. When used as a cathode for an OLED, examples of the first component include Li, Na, Mg, K, Ca, Cs, Yb, etc. Examples of the second component include Ag, Al, etc. The manufacturing method of the Mg-Ag alloy target is not limited to spraying of atomized powder, and it can be manufactured by any method such as casting, thermal spraying, sintering, etc.

[0072] The cylindrical target 2 made of the prepared Mg-Ag alloy was placed in a sputtering apparatus 1, and a film was formed on a substrate 6. A magnet unit 3 was disposed inside the target 2 (inside the backing tube 2a in the sputtering apparatus 1 of FIG. 4), and the orientation of the magnet unit 3 could be changed to any angle. Before starting film formation, the magnet unit 3 was adjusted to a predetermined angle θ, and sputtering film formation was performed while the target 2 was rotated at 10 rpm with the angle fixed.

[0073] The Ar gas pressure during sputtering deposition was 0.6 Pa, and the temperature of the substrate 6 was room temperature. The substrate 6 was transported above the target 2 in the direction indicated by the arrow S (see FIG. 7) at a predetermined speed to deposit the film.

[0074] The composition of the formed alloy thin film was analyzed by X-ray fluorescence. Here, the composition was analyzed by X-ray fluorescence, but other methods such as XRF (X-ray fluorescence), EDS (energy dispersive X-ray spectroscopy), EPMA (electron probe microanalyzer), XPS (X-ray photoelectron spectroscopy), SIMS (secondary ion mass spectrometry), GDMS (glow discharge mass spectrometry), and ICP (inductively coupled plasma mass spectrometry) can also be used to analyze the composition of the alloy thin film. Other methods such as transmission spectrum, reflection spectrum, emission spectrum, and spectroscopic ellipsometry can also be used.

[0075] Through intensive research, the inventors have found that when the angle θ of the magnet unit 3 in the backing tube 2a is changed to various angles to form a film, the Mg composition ratio of the formed alloy thin film changes depending on the angle θ. For example, when the angle θ of the magnet unit 3 is set to 0 degrees to form a film, the Mg composition ratio is 7.9 vol.%. On the other hand, when the angle θ of the magnet unit 3 is tilted to 20 degrees and 40 degrees to form a film, the Mg composition ratio is 8.4 vol.% and 9.4 vol.%, respectively. The results are shown in FIG. 14. In FIG. 14, the horizontal axis represents the angle θ of the magnet unit 3, and the vertical axis represents the Mg composition ratio of the formed alloy thin film. As shown in the results, the larger the angle θ of the magnet unit 3, the larger the Mg composition ratio of the obtained Mg-Ag alloy thin film. That is, the magnet unit 3 of this embodiment is configured so that the larger the angle from the reference position (θ=0 degrees) is, the larger the Mg composition ratio of the alloy thin film becomes. The fact that the Mg composition ratio of the Mg-Ag alloy thin film shows such a tendency is a new finding obtained by the present inventors through intensive research. Based on this finding, in this embodiment, the Mg composition ratio of the Mg-Ag alloy thin film is controlled by adjusting the angle θ of the magnet unit 3. It is a sign.

[0076] The inventors verified the above-mentioned relationship between the angle θ of the magnet unit 3 and the Mg composition ratio of the Mg-Ag alloy thin film formed from the following viewpoints. The angle θ of the magnet unit 3 was set to 0 degrees, and the substrate 6 was placed stationary directly above the cylindrical target 2 to perform sputtering, and the deposition amount distribution of Ag and Mg on the substrate 6 was examined. The results are shown in FIG. 15. In FIG. 15, the horizontal axis represents the distance from the position where the deposition amount (film thickness) is the largest on the substrate 6 (hereinafter referred to as the maximum film thickness position). In this embodiment, the maximum film thickness position is the intersection position of the line segment D1 and the substrate 6 when θ=0 in FIG. 7, and is the position closest to the rotation center O of the target 2. The vertical axis represents the value normalized by the film thickness at the maximum film thickness position. As shown in FIG. 15, the film thickness of both Mg and Ag became smaller as it moved away from the maximum film thickness position. In addition, the change (decrease) in the film thickness of Mg depending on the distance from the maximum film thickness position was more gradual than that of Ag. That is, the deposition amount distribution of Mg has a mountain shape with a wider width and a lower peak compared to the deposition amount distribution of Ag. This shows that the composition ratio of Mg is relatively higher at the wide-angle side position (position farther away from the maximum film thickness position) than at the maximum film thickness position, which is consistent with the result that the Mg composition ratio increases when the angle θ of the magnet unit 3 is increased during the transport and deposition as described above.

[0077] In this manner, in magnetron rotary sputtering deposition using an Mg-Ag alloy target, the Mg composition ratio of the deposited alloy thin film can be controlled by changing the angle θ of the magnet unit 3. Based on this knowledge, by controlling the sputtering apparatus 1 and the sputtering deposition process, it becomes possible to stably form an Mg-Ag alloy thin film having a desired Mg composition ratio.

[0078] Note that changing the angle θ of the magnet unit 3 changes not only the composition ratio but also the film thickness (film formation rate), but it is possible to obtain a desired film thickness by adjusting the voltage applied to the target 2 and the height of the magnet.

[0079] The above findings are not limited to Mg-Ag alloy targets, but can also be applied to magnetron rotary sputtering devices using alloy targets mainly composed of two kinds of materials that have different tendencies of film thickness change depending on the distance from the maximum film thickness position when magnetron rotary sputtering is performed, as shown in Fig. 15. That is, the target 2 is composed of an alloy of two or more components, and when a film is formed on a film-forming target using the target 2, the combination of two components is sufficient so that the deposition amount distribution of the first component has a mountain-like shape with a wider width and a lower peak than the deposition amount distribution of the second component. In addition, when the magnet unit 3 is configured so that the composition ratio of the first component of the alloy thin film increases as the angle from the reference position (the position of θ=0 degrees) increases, the control unit 14 increases the angle θ of the magnet unit 3 when the composition ratio of the first component is increased, and decreases the angle θ of the magnet unit 3 when the composition ratio of the first component is decreased, based on the composition ratio information of the alloy thin film.

[0080] In addition, when the magnet unit 3 is configured and the angle θ is defined such that the composition ratio of Mg (first component) increases as the absolute value of the angle from the reference position increases, as in this embodiment, the control unit 14 increases the absolute value of the angle θ of the magnet unit 3 when the composition ratio of Mg (first component) is to be increased, and decreases the absolute value of the angle θ of the magnet unit 3 when the composition ratio of Mg (first component) is to be decreased, based on the composition ratio information of the alloy thin film.

[0081] Depending on various conditions such as the shape, arrangement, and magnetic properties of each magnet constituting the magnet unit 3, the arrangement of the magnet unit 3 within the target 2, the components and composition ratio of the alloy constituting the target 2, the definition of the angle θ of the magnet unit 3, and the positional relationship between the target 2 and the substrate 6, the relationship between the angle θ of the magnet unit 3 and the Mg composition ratio may not necessarily be the same as the relationship shown in FIG. Even in such a case, the idea disclosed in the present invention makes it possible to control the Mg composition ratio with high precision by using the relationship between the angle θ of the magnet unit 3 in the actual sputtering apparatus 1 and the Mg composition ratio, and adjusting the angle θ of the magnet unit 3 based on the composition ratio information of the alloy thin film to be deposited.

[0082] <Specific control examples> When forming a film by sputtering in the sputtering apparatus 1, the control unit 14 acquires information on the composition ratio of the alloy thin film to be formed on the substrate 6 from the composition ratio acquisition unit 130. Examples of information acquired by the composition ratio acquisition unit 130 include information on the target composition ratio of the alloy thin film to be formed on the substrate 6, information on the composition ratio of the alloy material constituting the target 2, information on the composition ratio measured by an inspection device installed outside the sputtering apparatus 1 for alloy thin films previously formed in the sputtering apparatus 1, information on the relationship between the angle of the magnet unit 3 and the composition ratio, information on the change in the composition ratio due to the passage of time or the number of films formed when continuous film formation is performed for a long period of time, and the like. Examples of methods by which the composition ratio acquisition unit 130 acquires information on these composition ratios include input of information by a user, acquisition of information via a wired or wireless communication path from an external measuring device or experimental device, acquisition of information via a recording medium, acquisition of information by reading an optical identification pattern, and the like.

[0083] Based on such information on the composition ratio, the control unit 14 adjusts the angle of the magnet unit 3 before starting film formation. Below, several examples of the method for controlling the composition ratio by adjusting the angle of the magnet unit 3, which is characteristic of the present invention, will be described.

[0084] <Example 1> As an example of angle control of the magnet unit 3 based on the composition ratio information, a control for adjusting the angle θ of the magnet unit 3 according to the target Mg composition ratio for film formation and the Mg composition ratio of the target 2 can be used. The relationship between the angle θ of the magnet unit 3 and the Mg composition ratio can be a result measured in advance by an experiment or the like as shown in Fig. 14. The control unit 14 determines the angle θ of the magnet unit 3 during actual film formation based on the target Mg composition ratio, the Mg composition ratio of the target 2, and the previously obtained relationship between the angle θ of the magnet unit 3 and the Mg composition ratio.

[0085] For example, consider the case where an Mg-Ag alloy thin film of the first layer 63 of the cathode 65 is deposited by magnetron rotary sputtering. The Mg composition ratio of the target 2 is set to 10 vol.%, and the target value of the Mg composition ratio of the first layer 63 is set to 9 vol.%. In this case, as can be seen from the graph in Fig. 14, the first layer 63 having the target Mg composition ratio can be formed by depositing the film with the angle θ of the magnet unit 3 set to about 30 degrees.

[0086] Also, the Mg composition ratio can be adjusted to approach the target value by analyzing and measuring the Mg composition ratio of the actually deposited first layer 63 and fine-tuning the angle θ of the magnet unit 3 based on the results. For example, the angle θ of the magnet unit 3 is adjusted so that the difference between the Mg composition ratio and the target value is 0.5% or less.

[0087] <Example 2> A possible method for controlling the angle of the magnet unit 3 based on the composition ratio information is to feed back information on the Mg composition ratio of the thin film formed on the preceding substrate 6. In this control, when performing continuous film formation on a plurality of substrates 6, the angle θ of the magnet unit 3 is periodically adjusted to maintain the Mg composition ratio at a target value for a long period of time.

[0088] First, the first film is formed with the magnet unit 3 in the cylindrical target 2 facing vertically upward (angle θ=10 degrees). The Mg-Ag alloy thin film formed in this first film is subjected to composition analysis by fluorescent X-ray method to measure the first Mg composition ratio. Based on the difference information between the first Mg composition ratio and the target Mg composition ratio, the angle θ of the magnet unit 3 is changed. After changing the angle θ of the magnet unit 3, the second film is formed. By appropriately changing the angle θ of the magnet unit 3, the Mg composition ratio of the Mg-Ag alloy thin film obtained in the second film formation can be made closer to the target Mg composition ratio.

[0089] For example, if the target value of the Mg composition ratio is 9 vol.%, and the Mg composition ratio of the alloy thin film obtained by the first film formation is 8.4 vol.%, the angle θ of the magnet unit 3 is changed, for example, in a direction to increase by 10 degrees based on the information of the difference between this measurement evaluation value and the target value, and the second film formation is performed. The amount of change in the angle θ of the magnet unit 3 can be determined based on the relationship between the angle θ of the magnet unit 3 and the Mg composition ratio as shown in FIG. 14, which has been evaluated in advance by experiments or the like. The relationship between the angle θ of the magnet unit 3 and the Mg composition ratio is stored in the memory of the control unit 14 as a function or table. The amount of change in the angle θ of the magnet unit 3 can be obtained based on the relationship read from the memory and the difference between the target value obtained by measurement and the measurement evaluation value. In this way, in the alloy thin film obtained by the second film formation performed after changing the angle θ of the magnet unit 3, the Mg composition ratio approaches the target value (for example, 8.9 vol.%).

[0090] In this way, by repeating film formation, composition analysis, and adjustment of the angle θ of the magnet unit 3 (i.e., by feedback-controlling the angle θ of the magnet unit 3 based on composition evaluation information), it is possible to obtain an Mg-Ag alloy thin film having a target Mg composition ratio. In a continuous manufacturing process lasting for a long period of time (several hundred hours), the Mg composition ratio may vary over time, but even in such a case, by periodically adjusting the angle θ of the magnet unit 3 as described above, it is possible to stably form an alloy thin film having a Mg composition ratio close to the target for a long period of time.

[0091] Fig. 16 is a diagram showing the change over time in the Mg composition ratio of an alloy thin film obtained in a continuous manufacturing process over a long period of time. The solid line graph A shows the case where feedback control of the angle θ of the magnet unit 3 is performed, and the dashed line graph B shows the case where the angle θ of the magnet unit 3 is fixed. As shown in Fig. 16, when the angle θ of the magnet unit 3 is feedback controlled, the Mg composition ratio can be stably maintained over a long period of time during film formation.

[0092] The interval for adjusting the angle θ of the magnet unit 3 may be adjusted for each substrate on which a film is formed, or the angle θ of the magnet unit 3 may be feedback-controlled every time a predetermined number of substrates are formed (e.g., every 100 substrates). The angle θ of the magnet unit 3 may also be feedback-controlled every time a predetermined period of film formation is performed (e.g., every 50 hours). When the angle θ of the magnet unit 3 is changed, the film formation time or input power may be adjusted at the same time. By adjusting the film formation time or input power, not only the Mg composition ratio but also the film thickness can be maintained constant when forming a thin film.

[0093] <Example 3> As an example of controlling the angle of the magnet unit 3 based on the composition ratio information, a control that feeds forward information on the composition ratio change obtained from a film formation test before the start of film formation may be used.

[0094] In this control, a continuous film formation test is performed for a predetermined time (e.g., 500 hours) with the magnet unit 3 in the cylindrical target 2 at a predetermined angle (e.g., tilted 5 degrees from the vertical (angle θ=5 degrees)). In this continuous film formation test, the Mg composition ratio of the formed alloy thin film is periodically analyzed. A technique such as X-ray fluorescence analysis can be used for the composition analysis. This makes it possible to know in advance how the Mg composition ratio changes over time in continuous film formation using an Mg-Ag alloy target. Based on the results of this preliminary test, the time change in the Mg composition ratio in the actual continuous film formation can be predicted, and the angle θ of the magnet unit 3 can be adjusted according to the predicted Mg composition ratio. For example, in a preliminary test that started with an angle θ of 5 degrees and a target Mg composition ratio of 8.0 vol%, If the Mg composition ratio measured at 0 hours is 7.6 vol%, then the angle of the magnet unit 3 can be adjusted to θ=10 degrees after 50 hours of actual continuous film formation. This makes it possible to form a thin film with a constant Mg composition ratio during long-term continuous film formation.

[0095] Figure 17 is a diagram showing the change over time in the Mg composition ratio of a thin film obtained in a long-term continuous manufacturing process. The solid line graph A shows the case where the angle θ of the magnet unit 3 is feed-forward controlled based on the Mg composition ratio predicted from the results of a preliminary test, and the dashed line graph B shows the case where the angle θ of the magnet unit 3 is fixed. As shown in Figure 17, when the angle θ of the magnet unit 3 is feed-forward controlled, the Mg composition ratio can be stably maintained over a long period of time during film formation.

[0096] In the above example, the relationship between the elapsed time of continuous sputtering deposition and the Mg composition ratio is examined in a pre-test, and the relationship is fed forward to the angle control of the magnet unit 3 during actual deposition, but the relationship examined in the pre-test is not limited to this. For example, the relationship between the integrated value of the number of substrates on which films are formed by continuous sputtering deposition and the Mg composition ratio may be examined, and the angle of the magnet unit 3 may be adjusted according to the number of substrates on which films are formed during actual deposition.

[0097] <Example 4> A possible method for controlling the angle of the magnet unit 3 based on the composition ratio information is to feed back the composition ratio information obtained from a measuring means installed in the film forming apparatus. The measuring means is installed in the inspection chamber 105 of the in-line type film forming apparatus 100 shown in FIG.

[0098] 18, the substrate 6 is provided with an inspection region 330 for forming a film to evaluate the composition, in a region separate from the device region 340 in which the cathode 65 is formed. The inspection device in the inspection chamber 105 measures the composition of the alloy thin film formed in the inspection region 330 of the substrate 6. This makes it possible to evaluate the Mg composition ratio of the alloy thin film formed in the film formation chamber 104 without affecting the thin film formed in the device region 340.

[0099] The alloy thin film deposited in the deposition chamber 104 undergoes composition analysis in an inspection chamber 105 installed in the middle of the integrated vacuum production line, and the angle θ of the magnet unit 3 in the sputtering device 1 in the deposition chamber 104 is adjusted based on the composition analysis results. In this way, in the continuous thin film production process, the composition of the deposited alloy thin film can be monitored, and the angle θ of the magnet unit 3 can be adjusted based on this information, thereby feedback controlling the composition. This control reduces the time lag between deposition and adjustment of the angle θ of the magnet unit 3, and allows deposition to be performed with a constant composition ratio over long production periods.

[0100] The fourth embodiment can also be applied to a cluster-type film forming apparatus 111 as shown in Fig. 3. In this case, the measurement result of the Mg composition ratio in the inspection chamber 105 is fed back to adjust the angle θ of the magnet unit 3 of the sputtering apparatus 1 in the film forming chamber 104 of the second cluster C2. When sputtering apparatuses with the same settings as the sputtering apparatus 1 are provided in other clusters, the measurement result of the Mg composition ratio in the inspection chamber 105 may also be fed back to control those sputtering apparatuses.

[0101] <Example 5> A case will be described in which angle control of the magnet unit 3 based on composition ratio information is applied to a twin cathode sputtering apparatus 1Y shown in FIG. 9. Before a film formation process, the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R shown in FIG. 11 or 12 are calculated based on the composition ratio information, and the first magnet unit 3L and the second magnet unit 3R are rotated. After the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R are adjusted, the first magnet unit 3L is rotated at the adjusted angles. Sputtering film formation is performed with the first magnet unit 3L and the second magnet unit 3R kept stationary.

[0102] The relationship between the angle θ of the magnet unit 3 described in FIG. 14 and the composition ratio of the formed alloy thin film does not depend on the sign of the angle θ in the sputtering apparatus 1 of FIG. 4, the sputtering apparatus 1X of FIG. 8, and the sputtering apparatus 1Y of FIG. 9, and therefore the composition ratio of the alloy thin film does not change between the settings of FIG. 11 and FIG. 12.

[0103] In the configuration of the sputtering apparatus 1Y, as explained in the sputtering apparatus 1, the composition ratio of the alloy thin film can be controlled with high precision by adjusting the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R arranged in the first target 2L and the second target 2R, which are cylindrical cathodes, based on the composition ratio information of the alloy thin film formed on the substrate 6. In addition, by performing film formation multiple times with different angles θ of the magnet unit 3, it is possible to form a multilayer film with different composition ratios.

[0104] According to the control of the above-described Examples 1 to 5, in magnetron rotary sputtering deposition using an alloy target of two or more components, the angle θ of the magnet unit 3 arranged in the target 2, which is a cylindrical cathode, is adjusted based on composition ratio information of the alloy thin film deposited on the substrate 6, so that the composition ratio of the alloy thin film can be controlled with high precision. As a result, even when performing sputtering deposition over a long period of time, an alloy thin film with little composition variation can be deposited, and the variation in device characteristics between substrates can be reduced. This increases the production yield, and allows devices to be manufactured stably over a long period of time.

[0105] In addition, in the magnetron rotary sputtering film formation using an alloy target of two or more components as described in Examples 1 to 5, the film formation method of adjusting the angle θ of the magnet unit 3 based on composition ratio information of the alloy thin film formed on the substrate 6, and the film formation method of forming a multilayer film having different composition ratios (having a composition ratio gradient) in the film thickness direction by magnetron sputtering using a rotary target made of an alloy material of two components by changing the angle θ of the magnet unit 3 of the rotating cathode unit 8 and performing film formation multiple times can be applied to the in-line type film formation apparatus 100 shown in Figure 2, the cluster type film formation apparatus 111 shown in Figure 3, the substrate conveying type sputtering apparatus 1 shown in Figure 4, the rotating cathode unit moving type sputtering apparatus 1X shown in Figure 8, the twin cathode and rotating cathode unit moving type sputtering apparatus 1Y shown in Figure 9, the twin cathode and substrate conveying type sputtering apparatus not shown, and the magnet unit oscillating type sputtering apparatus shown in Figure 13.

[0106] The above embodiment shows an example of the present invention, but the present invention is not limited to the configuration of the above embodiment, and may be appropriately modified within the scope of its technical concept. For example, the present invention is not limited to the configuration in which the substrate moves relative to the rotating cathode unit fixed in the chamber, or the configuration in which the rotating cathode unit moves relative to the substrate fixed in the chamber, but may be, for example, a configuration in which the substrate and the rotating cathode unit are fixed in the chamber, and the number of targets constituting the rotating cathode unit is increased so that the sputtering region as a whole covers the entire film formation target region, a configuration in which the substrate oscillates in a horizontal plane relative to the rotating cathode unit fixed in the chamber, or a configuration in which the rotating cathode unit oscillates in a horizontal plane relative to the substrate fixed in the chamber. Although a twin cathode type sputtering device having two targets is illustrated in FIG. 9, the number of targets may be three or more. [Explanation of symbols]

[0107] 1: Sputtering equipment 2: Target 3: Magnet unit 6: Substrate 35: Rotation axis 100: Film deposition equipment

Claims

1. a cylindrical target made of an alloy of two or more components; a magnetic field generating means provided inside the target, the magnetic field generating means being capable of varying the angle around a rotation axis parallel to the central axis of the cylindrical shape, and generating a leakage magnetic field leaking from the outer peripheral surface of the target; a control unit that controls the angle of the magnetic field generating means; and A film formation apparatus that forms an alloy thin film by sputtering on a film formation target that is disposed opposite the target while rotating the target, The film forming apparatus is characterized in that the control unit controls the angle of the magnetic field generating means based on information about the composition ratio of the alloy thin film.

2. A film forming apparatus as described in Claim 1, wherein the control unit controls the angle of the magnetic field generating means based on the composition ratio of the alloy constituting the target and the target value of the composition ratio of the alloy thin film to be formed on the film forming object.

3. The film forming apparatus of claim 1, wherein when the film forming apparatus continuously forms films on multiple film forming targets, the control unit controls the angle of the magnetic field generating means based on information on the composition ratio of the alloy thin film on the film forming target on which film formation has been performed previously.

4. The film forming apparatus described in Claim 1, wherein the control unit controls the angle of the magnetic field generating means based on information on the change over time in the composition ratio of the alloy thin film formed when film formation is performed continuously on multiple film forming objects, which information has been obtained experimentally in advance.

5. a measuring means for measuring a composition ratio of the alloy thin film formed on the film-forming target, 2. The film deposition apparatus according to claim 1, wherein the control unit controls the angle of the magnetic field generating means based on information about the composition ratio measured by the measuring means.

6. A film forming apparatus described in any one of claims 1 to 5, wherein the control unit controls the angle of the magnetic field generating means based on a predetermined relationship between the angle of the magnetic field generating means and the composition ratio of the alloy thin film to be formed on the film forming object.

7. A film forming apparatus according to any one of claims 1 to 5, wherein when the film forming apparatus continuously forms films on a plurality of the film forming objects, the control unit adjusts the angle of the magnetic field generating means each time film formation is performed on a predetermined number of the film forming objects.

8. A film forming apparatus according to any one of claims 1 to 5, wherein when the film forming apparatus continuously forms films on a plurality of the film forming objects, the control unit adjusts the angle of the magnetic field generating means every time film formation is performed for a predetermined period of time.

9. A film forming apparatus described in any one of claims 1 to 5, wherein the control unit controls the angle of the magnetic field generating means so that the difference between the composition ratio of the alloy thin film and the target composition ratio is 0.5% or less.

10. 6. The film deposition apparatus according to claim 1, wherein the first component of the alloy constituting the target is Mg and the second component is Ag.

11. The film forming apparatus according to any one of claims 1 to 5, wherein the first component of the alloy constituting the target is one of Li, Na, Mg, K, Ca, Cs, and Yb, and the second component is Ag or Al.

12. A film forming apparatus according to any one of claims 1 to 5, wherein when a film is formed on the film forming object using the target, the deposition amount distribution of the first component of the alloy constituting the target has a mountain-like shape that is wider and has a lower peak than the deposition amount distribution of the second component.

13. the magnetic field generating means is configured so that the composition ratio of the first component in the alloy thin film increases as the angle from a reference position increases, The film forming apparatus of claim 10, wherein the control unit increases the angle of the magnetic field generating means when the composition ratio of the first component is increased based on the composition ratio of the alloy thin film, and decreases the angle of the magnetic field generating means when the composition ratio of the first component is decreased.

14. 6. The film deposition apparatus according to claim 1, wherein at least one of a voltage applied to the target and a film deposition time is adjusted according to an angle of the magnetic field generating means.

15. 6. The film forming apparatus according to claim 1, wherein the film is continuously formed on a plurality of the film forming targets.

16. 6. The film forming apparatus according to claim 1, wherein the alloy thin film constitutes a cathode of an organic EL element.

17. 6. The film forming apparatus according to claim 1, wherein the film forming apparatus is an in-line type film forming apparatus.

18. 6. The film forming apparatus according to claim 1, wherein the film forming apparatus is a cluster type film forming apparatus.

19. A film forming apparatus according to claim 1, further comprising a composition ratio acquisition unit for acquiring information on the composition ratio of the alloy thin film.

20. a cylindrical target made of an alloy of two or more components; a magnetic field generating means provided inside the target, the magnetic field generating means being capable of varying the angle around a rotation axis parallel to the central axis of the cylindrical shape, and generating a leakage magnetic field leaking from the outer peripheral surface of the target; A film formation method using a film formation apparatus having the following: forming an alloy thin film by sputtering on a film-forming target disposed opposite the target while rotating the target; controlling the angle of the magnetic field generating means based on information about the composition ratio of the alloy thin film; A film forming method comprising the steps of:

21. A method for manufacturing an electronic device, comprising manufacturing the electronic device by using the film forming method according to claim 20.

Images