CN111364008A

CN111364008A - Negative ion generating device

Info

Publication number: CN111364008A
Application number: CN202010216059.XA
Authority: CN
Inventors: 北见尚久; 酒见俊之; 山本哲也; 野本淳一
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2015-07-21
Filing date: 2016-07-21
Publication date: 2020-07-03
Anticipated expiration: 2036-07-21
Also published as: KR20200032276A; KR20230129601A; WO2017014278A1; KR102573358B1; CN111364008B

Abstract

The present invention provides an anion generating device for irradiating negative ions to an object, comprising: a plasma source for supplying plasma into the vacuum chamber; and a unit for lowering the electron temperature of the plasma in the vacuum chamber.

Description

Negative ion generating device

The present application is a divisional application of the original application having an application date of 2016, 7, 21, and an application number of 201680045499.5, entitled "film deposition apparatus".

Technical Field

The present invention relates to an anion generating apparatus.

Background

As a film forming apparatus for forming a film on a surface of an object to be film formed, for example, there is known a film forming apparatus based on an ion plating method in which particles of a film forming material that have been evaporated are diffused into a vacuum chamber and the particles of the film forming material are attached to the surface of the object to be film formed (see patent document 1).

Prior art documents

Patent document

Patent document 1: japanese patent laid-open No. 2000-282226

Disclosure of Invention

Technical problem to be solved by the invention

In the above-described conventional film forming apparatus, when the object to be film-formed on which the film is formed is discharged into the atmosphere, oxygen in the atmosphere adheres to the surface of the film on the object to be film-formed. When oxygen adheres to the film, the film quality may be lowered.

More specifically, for example, when a ZnO film formed on an object to be film-formed is used as a film for detecting a gas of a semiconductor type hydrogen sensor, oxygen in the atmosphere is represented by O^2-The form of (2) is adhered to the surface of the ZnO film, and thus there is a problem that the detection response of hydrogen is lowered.

Accordingly, an object of the present invention is to provide a film deposition apparatus capable of suppressing a decrease in film quality on an object to be film deposited.

Means for solving the technical problem

In order to solve the above problem, a film forming apparatus according to one aspect of the present invention is a film forming apparatus for forming a film of a film forming material on an object to be film formed, the film forming apparatus including: a vacuum chamber for accommodating an object to be film-formed and performing a film formation process; a film forming unit for attaching particles of a film forming material to an object to be film formed in a vacuum chamber; and a negative ion generating unit for generating negative ions in the vacuum chamber.

In the film forming apparatus according to one aspect of the present invention, the negative ion generator generates negative ions in the vacuum chamber, and therefore the negative ions can be attached to the surface of the film formed on the object to be film formed by the film forming process. Thus, even when the object to be film-formed after the film-forming process is discharged into the atmosphere, negative ions adhere to the surface of the film formed on the object to be film-formed, and thus the deterioration of the film quality due to the adhesion of oxygen in the atmosphere to the surface of the film on the object to be film-formed can be suppressed. As described above, the film quality of the object to be film-formed can be suppressed from decreasing.

In the film forming apparatus, the negative ion generating unit may include: a plasma gun generating plasma in the vacuum chamber; a raw material gas supply unit for supplying a raw material gas of negative ions into the vacuum chamber; and a control unit for controlling the plasma gun to intermittently generate plasma. In this case, since the plasma is intermittently generated in the vacuum chamber, when the generation of the plasma in the vacuum chamber is stopped, the electron temperature of the plasma in the vacuum chamber is rapidly lowered, and the electrons are likely to adhere to particles of the negative ion source gas supplied into the vacuum chamber. This enables negative ions to be efficiently generated in the vacuum chamber. As a result, negative ions can be effectively attached to the surface of the film formed on the object to be film-formed. As described above, the film quality of the object to be film-formed can be reliably suppressed from decreasing.

In the film forming apparatus, the negative ion generating unit may further include a switching unit that switches between supply and interruption of the plasma into the vacuum chamber, and the control unit may control the plasma gun to intermittently generate the plasma by switching the switching unit. In this case, the plasma can be generated intermittently by simply switching the switching portion with ease.

The film deposition apparatus may further include a magnetic field generating coil that generates a magnetic field having magnetic lines of force in a direction intersecting a direction from the film deposition chamber toward the transport chamber to suppress electrons in the film deposition chamber from flowing into the transport chamber. In this case, the electrons in the film forming chamber can be suppressed from flowing into the transport chamber by the magnetic field generated by the magnetic field generating coil, and therefore, the negative ions can be generated more efficiently in the film forming chamber. As a result, the negative ions can be more effectively attached to the surface of the film formed on the object to be film-formed.

In the film forming apparatus, the magnetic field generating coil may be provided in the vacuum chamber between the film forming chamber and the transport chamber. In this case, a magnetic field having magnetic lines of force in a direction in which electrons in the film formation chamber are suppressed from flowing into the transport chamber can be generated appropriately.

In the film forming apparatus, the film forming section may include a plasma gun, particles of the film forming material may be attached to the object to be film formed by ion plating, and the plasma gun of the film forming section may also serve as the plasma gun of the negative ion generating section. In this case, since the plasma gun of the film forming section and the plasma gun of the negative ion generating section are used in combination, the negative ion generating section can be configured without significantly changing the structure originally provided in the vacuum chamber as a structure necessary for the film forming process. Therefore, the negative ion generating part can be provided while suppressing the influence on the film forming conditions. Further, the plasma torch can be used as well, thereby simplifying the apparatus configuration.

The film forming apparatus may further include: and a voltage applying unit for applying a positive bias voltage to the object to be film-formed after the film-forming process by the film-forming unit. In this case, a positive bias voltage is applied to the film formation object after the film formation process by the voltage application unit. In this way, the negative ions generated by the negative ion generating unit are attracted to the object to be film-formed, and are irradiated onto the surface of the film formed on the object to be film-formed. As a result, the film quality can be prevented from being lowered due to the adhesion of oxygen in the atmosphere to the surface of the film on the object to be film-formed.

In the film forming apparatus, the negative ion generating unit may intermittently generate plasma in the vacuum chamber, and the voltage applying unit may apply a positive bias voltage to the object to be film-formed after stopping the generation of the plasma by the negative ion generating unit. Thereby, a large amount of oxygen anions are irradiated to the object to be film-formed. As a result, the film quality can be further suppressed from being lowered due to the adhesion of oxygen in the atmosphere to the surface of the film on the object to be film-formed.

The film forming apparatus may include: and a load lock chamber which is disposed adjacent to the vacuum chamber and carries in and out the object to be film-formed, wherein the load lock chamber carries in the object to be film-formed after the film-forming process from the vacuum chamber, and carries out the carried-in object to be film-formed to the vacuum chamber after the negative ions are generated by the negative ion generator. Thus, the object to be film-formed is carried into the vacuum chamber at an appropriate timing when the oxygen anions are generated without being exposed to the atmosphere. As a result, the object to be film-formed can be appropriately irradiated with oxygen anions.

The film forming apparatus may include: the holding member holds an object to be film-formed, an overhead wire extends in the vacuum chamber, and a power supply unit for supplying power from the overhead wire is provided in the holding member. In this case, the power supply unit provided in the holding member for holding the object to be film-formed supplies power from the overhead wire provided in the vacuum chamber. Thus, a positive voltage can be easily applied to the object to be film-formed by the power supply portion of the holding member.

The film forming apparatus may include: a tension applying part for applying tension to the overhead wire. In this case, the tension applying unit applies tension to the overhead wire. This can suppress the deflection even when the overhead wire expands or contracts due to heat generated in the vacuum chamber.

Effects of the invention

According to the present invention, a film forming apparatus capable of suppressing a decrease in film quality on an object to be film-formed can be provided.

Drawings

Fig. 1 is a schematic cross-sectional view showing a configuration of a film deposition apparatus according to embodiment 1 of the present invention, and is a view showing an operation state in a film deposition process mode.

Fig. 2 is a schematic cross-sectional view showing the structure of the film formation apparatus of fig. 1, and is a view showing an operation state in an oxygen anion generation mode.

Fig. 3 is a flowchart illustrating a film formation method of the film formation apparatus according to embodiment 1 of the present invention.

Fig. 4 is a schematic cross-sectional view showing the structure of a film formation apparatus according to embodiment 2 of the present invention, and is a view showing an operation state in an oxygen anion generation mode.

Fig. 5 is a schematic front view and a schematic side view showing a structure of the overhead wire fixing end portion of fig. 4.

Fig. 6 is a schematic plan view showing the structure of the object holding member for film formation of fig. 4.

Fig. 7 is a sectional view taken along line VII-VII of fig. 6.

Fig. 8 is a sectional view taken along line VIII-VIII of fig. 6.

Fig. 9 is a diagram illustrating an operation of the brush body guided by the brush guide.

Fig. 10 is a diagram illustrating an operation of the power supply terminal unit.

Fig. 11 is a graph showing the change in flux of ions present in a vacuum chamber with time.

Fig. 12 is a graph showing the relationship between the absence of application of the bias voltage and the carrier density.

Fig. 13 is a graph showing the relationship between the application of the bias voltage and the optical mobility.

Fig. 14 is a graph showing a relationship between the presence or absence of oxygen anion irradiation and the characteristics of the hydrogen sensor.

Detailed Description

Hereinafter, a film deposition apparatus according to an embodiment of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

(embodiment 1)

First, the structure of a film deposition apparatus according to embodiment 1 of the present invention will be described with reference to fig. 1 and 2. Fig. 1 and 2 are schematic cross-sectional views showing the structure of a film deposition apparatus according to the present embodiment. Fig. 1 shows an operation state in a film formation processing mode, and fig. 2 shows an operation state in an oxygen anion generation mode. The details of the generation processing mode and the oxygen anion generation mode will be described later.

As shown in fig. 1 and 2, the film deposition apparatus 1 according to the present embodiment is an ion plating apparatus used in a so-called ion plating method. For convenience of explanation, fig. 1 and 2 show XYZ coordinate systems. The Y-axis direction is a direction in which a film formation object is conveyed, which will be described later. The X-axis direction is a position where the object to be film-formed faces a hearth mechanism described later. The Z-axis direction is a direction orthogonal to the Y-axis direction and the X-axis direction.

The film deposition apparatus 1 is a so-called vertical film deposition apparatus that conveys the film deposition object 11 while the film deposition object 11 is placed in the vacuum chamber 10 in a state in which the film deposition object 11 is upright or inclined from the upright state so that the thickness direction of the film deposition object 11 is horizontal (the X-axis direction in fig. 1 and 2). In this case, the X-axis direction is a horizontal direction and a thickness direction of the film formation object 11, the Y-axis direction is a horizontal direction, and the Z-axis direction is a vertical direction. The film forming apparatus according to an embodiment of the present invention may be a so-called horizontal film forming apparatus in which a film forming object is placed in a vacuum chamber and conveyed so that a thickness direction of the film forming object is substantially perpendicular to the film forming object. In this case, the Z-axis and Y-axis directions are horizontal directions, and the X-axis direction is a vertical direction and a plate thickness direction. Hereinafter, a vertical film forming apparatus will be described as an example.

The film forming apparatus 1 includes a vacuum chamber 10, a conveying mechanism 3, a film forming section 14, a negative ion generating section 24, and a magnetic field generating coil 30.

The vacuum chamber 10 accommodates an object 11 to be film-formed and performs a film formation process. The vacuum chamber 10 has: a transport chamber 10a for transporting a film formation object 11 for forming a film of a film formation material Ma; a film forming chamber 10b for diffusing the film forming material Ma; and a plasma port 10c for accommodating the plasma P irradiated in a beam shape from the plasma source 7 in the vacuum chamber 10. The transport chamber 10a, the film forming chamber 10b, and the plasma port 10c communicate with each other. The conveyance chamber 10a is set in a predetermined conveyance direction (arrow a in the figure) (along the Y axis). The vacuum chamber 10 is made of a conductive material and is connected to a ground potential.

The film forming chamber 10b includes, as a wall portion 10w, a pair of side walls extending in the transport direction (arrow a), a pair of

side walls

10h and 10i extending in a direction (Z-axis direction) intersecting with the transport direction (arrow a), and a bottom wall 10j extending in the X-axis direction.

The conveyance mechanism 3 conveys the object holding member 16 holding the object 11 in a state facing the film forming material Ma in the conveyance direction (arrow a). For example, the object holding member 16 is a frame that holds the outer peripheral edge of the object 11. The conveyance mechanism 3 is constituted by a plurality of conveyance rollers 15 provided in the conveyance chamber 10 a. The transport rollers 15 are arranged at equal intervals in the transport direction (arrow a), and transport the film formation object holding member 16 in the transport direction (arrow a) while supporting it. The object 11 to be film-formed is a plate-like member such as a glass substrate or a plastic substrate.

Next, the structure of the film forming section 14 will be described in detail. The deposition section 14 attaches particles of the deposition material Ma to the object 11 to be deposited by ion plating. The film forming section 14 includes a plasma source 7, a turning coil 5, a hearth mechanism 2, and a ring hearth 6.

The plasma source 7 is, for example, a pressure gradient type plasma gun, and a main body thereof is connected to the film forming chamber 10b through a plasma port 10c provided in a side wall of the film forming chamber 10 b. The plasma source 7 generates plasma P within the vacuum chamber 10. The plasma P generated by the plasma source 7 is emitted in a beam shape from the plasma port 10c into the film forming chamber 10 b. Thereby, plasma P is generated in the film forming chamber 10 b.

One end of the plasma source 7 is closed by a cathode 60. A 1 st intermediate electrode (grid) 61 and a 2 nd intermediate electrode (grid) 62 are concentrically disposed between the cathode 60 and the plasma port 10 c. The 1 st intermediate electrode 61 incorporates a ring-shaped permanent magnet 61a for converging the plasma P. The 2 nd intermediate electrode 62 also incorporates an electromagnet coil 62a for converging the plasma P. The plasma source 7 also functions as an anion generator 24 described later. The details of this will be described later in the description of the negative ion generating unit 24.

The steering coil 5 is disposed around the plasma port 10c where the plasma source is installed. The turn coil 5 guides the plasma P into the film forming chamber 10 b. The steering coil 5 is excited by a power supply for the steering coil (not shown).

The hearth mechanism 2 holds the film forming material Ma. The crucible mechanism 2 is provided in the film forming chamber 10b of the vacuum chamber 10 and is disposed in the negative direction of the X-axis direction when viewed from the conveyance mechanism 3. The hearth mechanism 2 has a main hearth 17 as a main anode for guiding the plasma P emitted from the plasma source 7 to the film forming material Ma or as a main anode for guiding the plasma P emitted from the plasma source 7.

The main furnace hearth 17 has a cylindrical packed portion 17a extending in the positive direction of the X-axis direction and packed with the film forming material Ma, and a flange portion 17b protruding from the packed portion 17 a. The main crucible 17 is kept at a positive potential with respect to the ground potential that the vacuum chamber 10 has, and therefore attracts the plasma P. A through hole 17c for filling the film forming material Ma is formed in the filling portion 17a of the main furnace 17 into which the plasma P is incident. The front end portion of the film forming material Ma is exposed to the film forming chamber 10b at one end of the through hole 17 c.

Examples of the film forming material Ma include transparent conductive materials such as ITO and ZnO, and insulating sealing materials such as SiON. When the film formation material Ma is made of an insulating material, when the main furnace 17 is irradiated with the plasma P, the main furnace 17 is heated by the current from the plasma P, the front end portion of the film formation material Ma is evaporated or sublimated, and the film formation material particles (evaporation particles) Mb ionized by the plasma P are diffused into the film formation chamber 10 b. When the film formation material Ma is made of a conductive material, when the main furnace 17 is irradiated with the plasma P, the plasma P is directly incident on the film formation material Ma, the front end portion of the film formation material Ma is heated to evaporate or sublimate, and the film formation material particles Mb ionized by the plasma P diffuse into the film formation chamber 10 b. The film forming material particles Mb diffused into the film forming chamber 10b move in the positive X-axis direction of the film forming chamber 10b, and adhere to the surface of the object 11 to be film formed in the transport chamber 10 a. The film forming material Ma is a solid material formed into a cylindrical shape having a predetermined length, and a plurality of film forming materials Ma are charged into the hearth mechanism 2 at one time. Then, the film forming material Ma is extruded in order from the X negative direction side of the hearth mechanism 2 in accordance with the consumption of the film forming material Ma so that the front end portion of the film forming material Ma on the forefront side and the upper end of the main hearth 17 are kept in a predetermined positional relationship.

The ring hearth 6 is an auxiliary anode having an electromagnet for inducing the plasma P. The ring furnace hearth 6 is disposed around the filling portion 17a of the main furnace hearth 17 that holds the film forming material Ma. The ring hearth 6 includes a ring-shaped coil 9, a ring-shaped permanent magnet portion 20, and a ring-shaped container 12, and the coil 9 and the permanent magnet portion 20 are accommodated in the container 12. In the present embodiment, the coil 9 and the permanent magnet portion 20 are provided in this order in the X negative direction when viewed from the conveyance mechanism 3, but the permanent magnet portion 20 and the coil 9 may be provided in this order in the X negative direction. The ring hearth 6 controls the direction of the plasma P incident on the film forming material Ma or the direction of the plasma P incident on the main hearth 17 according to the magnitude of the current flowing through the coil 9.

Next, the structure of the negative ion generator 24 will be described in detail. The negative ion generator 24 includes a plasma source 7, a source gas supplier 40, a controller 50, and a circuit 34. In addition, some functions included in the control unit 50 and the circuit unit 34 also belong to the film forming unit 14 described above.

The plasma source 7 is the same plasma source as the plasma source 7 of the film forming section 14. That is, in the present embodiment, the plasma source 7 of the film formation section 14 also serves as the plasma source 7 of the negative ion generation section 24. The plasma source 7 functions as the film formation section 14 and also functions as the negative ion generation section 24. Further, the film forming section 14 and the negative ion generating section 24 may have different plasma sources.

The plasma source 7 intermittently generates plasma P in the film forming chamber 10 b. Specifically, the plasma source 7 is controlled by a control unit 50, which will be described later, so as to intermittently generate plasma P in the film forming chamber 10 b. This control will be described in detail in the following description of the control unit 50.

The source gas supply unit 40 is disposed outside the vacuum chamber 10. The raw material gas supply unit 40 supplies oxygen gas, which is a raw material gas of oxygen anions, into the vacuum chamber 10 through a gas supply port 41 provided in a side wall (for example, the side wall 10h) of the film formation chamber 10 b. The source gas supply unit 40 starts supplying oxygen gas when, for example, the film formation process mode is switched to the oxygen anion generation mode. The source gas supply unit 40 may continue to supply oxygen gas in both the film formation process mode and the oxygen anion generation mode.

The position of the gas supply port 41 is preferably a position near the boundary between the film forming chamber 10b and the transport chamber 10 a. In this case, since the oxygen gas from the raw material gas supply unit 40 can be supplied to the vicinity of the boundary between the film forming chamber 10b and the transfer chamber 10a, oxygen anions to be described later are generated in the vicinity of the boundary. Accordingly, the generated oxygen anions can be appropriately attached to the object 11 to be film-formed in the transfer chamber 10 a. The position of the gas supply port 41 is not limited to the vicinity of the boundary between the film forming chamber 10b and the transport chamber 10 a.

The controller 50 is disposed outside the vacuum chamber 10. The control unit 50 switches the switching unit included in the circuit unit 34. The switching of the switching unit by the control unit 50 will be described in detail below together with the description of the circuit unit 34.

The circuit unit 34 includes a variable power source 80, a 1 st wiring 71, a 2 nd wiring 72, resistors R1 to R4, and short-circuit switches SW1 and SW 2.

The variable power supply 80 applies a negative voltage to the cathode 60 of the plasma source 7 and a positive voltage to the main hearth 17 of the hearth mechanism 2 across the vacuum chamber 10 at ground potential. Thereby, the variable power source 80 generates a potential difference between the cathode 60 of the plasma source 7 and the main hearth 17 of the hearth mechanism 2.

The 1 st wiring 71 electrically connects the cathode 60 of the plasma source 7 and the negative potential side of the variable power supply 80. The 2 nd wire 72 electrically connects the main hearth 17 (anode) of the hearth mechanism 2 and the positive potential side of the variable power supply 80.

One end of the resistor R1 is electrically connected to the 1 st intermediate electrode 61 of the plasma source 7, while the other end is electrically connected to the variable power supply 80 via the 2 nd wiring 72. That is, the resistor R1 is connected in series between the 1 st intermediate electrode 61 and the variable power supply 80.

One end of the resistor R2 is electrically connected to the 2 nd intermediate electrode 62 of the plasma source 7, and the other end is electrically connected to the variable power supply 80 via the 2 nd wiring 72. That is, the resistor R2 is connected in series between the 2 nd intermediate electrode 62 and the variable power supply 80.

One end of the resistor R3 is electrically connected to the wall portion 10w of the film forming chamber 10b, and the other end is electrically connected to the variable power supply 80 via the 2 nd wiring 72. That is, the resistor R3 is connected in series between the wall 10w of the film forming chamber 10b and the variable power source 80.

One end of the resistor R4 is electrically connected to the ring furnace cylinder 6, and the other end is electrically connected to the variable power source 80 via the 2 nd wiring 72. That is, the resistor R4 is connected in series between the ring furnace cylinder 6 and the variable power source 80.

The short-circuit switches SW1 and SW2 are switching units that are switched on/off by receiving a command signal from the control unit 50.

The short-circuit switch SW1 is connected in parallel with the resistor R2. The short-circuit switch SW1 is switched on/off by the control unit 50 depending on whether the film formation processing mode or the oxygen anion mode is set. The short-circuit switch SW1 is off in the film formation processing mode. Thus, in the film formation process mode, the 2 nd intermediate electrode 62 and the variable power supply 80 are electrically connected to each other via the resistor R2, and thus it is difficult for a current to flow between the 2 nd intermediate electrode 62 and the variable power supply 80. As a result, the plasma P from the plasma source 7 is emitted into the vacuum chamber 10 and is incident on the film formation material Ma (see fig. 1).

On the other hand, in the oxygen anion generation mode, the short-circuit switch SW1 intermittently generates the plasma P from the plasma source 7 in the vacuum chamber 10, and therefore, the on/off state is switched at predetermined intervals by the control unit 50. When the short-circuit switch SW1 is switched to the on state, the electrical connection between the 2 nd intermediate electrode 62 and the variable power source 80 is short-circuited, and thus a current flows between the 2 nd intermediate electrode 62 and the variable power source 80. That is, a short-circuit current flows through the plasma source 7. As a result, the plasma P from the plasma source 7 cannot be emitted into the vacuum chamber 10.

If the short switch SW1 is switched to the off state, the 2 nd intermediate electrode 62 and the variable power source 80 are electrically connected to each other via the resistor R2, and thus it is difficult for current to flow between the 2 nd intermediate electrode 62 and the variable power source 80. As a result, the plasma P from the plasma source 7 is emitted into the vacuum chamber 10. In this way, the controller 50 switches the on/off state of the short switch SW1 at predetermined intervals, thereby intermittently generating plasma P from the plasma source 7 in the vacuum chamber 10. That is, the short-circuit switch SW1 is a switching unit that switches between supply and interruption of the plasma P into the vacuum chamber 10.

The short-circuit switch SW2 is connected in parallel with the resistor R4. The short-circuit switch SW2 is switched between on and off by the control unit 50 depending on whether the film formation processing mode is a standby mode, which is a state before the film formation processing mode is started and before the film formation object 11 is conveyed, or the film formation processing mode. The short-circuit switch SW2 is in an on state in the standby mode. Accordingly, since the electrical connection between the ring hearth 6 and the variable power source 80 is short-circuited, the current flows more easily through the ring hearth 6 than through the main hearth 17, and thus the film forming material Ma can be prevented from being unnecessarily consumed.

On the other hand, the short-circuit switch SW2 is off in the film formation processing mode. Accordingly, since the ring hearth 6 and the variable power source 80 are electrically connected via the resistor R4, the current flows more easily through the main hearth 17 than the ring hearth 6, and the emission direction of the plasma P can be appropriately directed toward the film forming material Ma. In addition, the short-circuit switch SW2 may be in either an on state or an off state in the oxygen anion generation mode.

The magnetic field generating coil 30 is disposed in the vacuum chamber 10 between the film forming chamber 10b and the transport chamber 10 a. The magnetic field generating coil 30 is disposed between the hearth mechanism 2 and the conveying mechanism 3, for example. More specifically, the magnetic field generating coil 30 is disposed so as to be sandwiched between the end of the film forming chamber 10b on the side of the transport chamber 10a and the end of the film forming chamber 10a on the side of the transport chamber 10 b. The magnetic field generating coil 30 has a pair of

coils

30a and 30b facing each other. The

coils

30a and 30b face each other in a direction intersecting a direction from the film forming chamber 10b to the transport chamber 10a (a direction from the hearth mechanism 2 to the transport mechanism 3), for example.

The magnetic field generating coil 30 is not excited in the film formation processing mode, and is excited by a power supply (not shown) for the magnetic field generating coil 30 in the oxygen anion generation mode. Here, the film formation process mode refers to a mode in which a film formation process is performed on the object 11 to be film-formed in the vacuum chamber 10. The negative oxygen ion generation mode is a mode in which negative oxygen ions are generated in the vacuum chamber 10 to adhere to the surface of the film formed on the object 11. The magnetic field generating coil 30 is excited in the oxygen anion generation mode, whereby a sealing magnetic field M (refer to fig. 2) having magnetic lines of force extending in a direction intersecting a direction from the film forming chamber 10b toward the transport chamber 10a (a direction from the crucible mechanism 2 toward the transport mechanism 3) is formed within the vacuum chamber 10. The magnetic field generating coil 30 generates such a sealing magnetic field M, thereby suppressing the electrons in the film forming chamber 10b from flowing into the transfer chamber 10 a. The magnetic lines of force of the sealing magnetic field M may have, for example, a portion extending in a direction substantially parallel to the transport direction (arrow a) of the object 11 to be film-formed. Switching of the on/off state of the power supply for the magnetic field generating coil 30 can be controlled by a control unit 50 described later. The magnetic field generating coil 30 is covered with a case 31 so as not to accumulate the film forming material Ma. In addition, the magnetic field generating coil 30 may not be covered by the case 31.

Next, a film formation method of the film formation apparatus 1 will be described in detail with reference to fig. 3. Fig. 3 is a flowchart illustrating a film formation method of the film formation apparatus 1.

As shown in fig. 3, in the film forming apparatus 1, when the control unit 50 switches to the film forming process mode, a film of the film forming material Ma is formed on the object 11 (S1: film forming step). At this time, the short-circuit switch SW1 is switched to the off state by the control unit 50. In the film formation process mode, the steering coil 5 is excited, but the magnetic field generating coil 30 is not excited. Thereby, plasma P is generated in the film forming chamber 10b by the plasma source 7, and the plasma P is irradiated to the main hearth 17 (refer to fig. 1). As a result, the film formation material Ma in the main furnace 17 is ionized by the plasma P to form film formation material particles Mb, and the particles are diffused into the film formation chamber 10b and adhere to the surface of the object 11 to be film formed in the transfer chamber 10 a. In this way, the film of the film forming material Ma is formed on the object 11 to be film-formed, and the film forming step S1 is terminated.

Then, in the film forming apparatus 1, oxygen anions are generated in the oxygen anion mode (S2: oxygen anion generating step). The oxygen anion generating step S2 will be specifically described below. First, oxygen gas is supplied into the film forming chamber 10b by the source gas supply unit 40 (S21: source gas supply step).

Subsequently, the control unit 50 controls the plasma source 7 to intermittently generate plasma P from the plasma source 7 in the film forming chamber 10b (S22: plasma generating step). For example, the control unit 50 switches the on/off state of the short switch SW1 at predetermined intervals, thereby intermittently generating the plasma P from the plasma source 7 in the film forming chamber 10 b.

When the short-circuit switch SW1 is turned on, the plasma P from the plasma source 7 is not emitted into the film forming chamber 10b, and therefore the electron temperature of the plasma P in the film forming chamber 10b is rapidly decreased. Therefore, the electrons of the plasma P are likely to adhere to the particles of the oxygen gas supplied into the film forming chamber 10b in the raw material gas supply step S21. Thereby, oxygen anions are efficiently generated in the film forming chamber 10 b.

Subsequently, the control unit 50 forms a sealing magnetic field M in the vacuum chamber 10 (S23: sealing magnetic field forming step). For example, the magnetic field generating coil 30 is excited to form a sealing magnetic field M (see fig. 2) in the vacuum chamber 10 so as to be sandwiched between the film forming chamber 10b and the transport chamber 10 a. The sealing magnetic field M has magnetic lines extending in a direction intersecting a direction from the film forming chamber 10b to the transport chamber 10a (a direction from the crucible mechanism 2 to the transport mechanism 3).

Electrons of the plasma P in the film forming chamber 10b generated in the plasma generating step S22 are inhibited from flowing into the transfer chamber 10a by being disturbed by the magnetic lines of force of the sealing magnetic field M formed in the sealing magnetic field forming step S23. This makes it easier for electrons in the plasma P to adhere to particles of oxygen in the film forming chamber 10b, and thereby more efficiently generates oxygen anions. The oxygen anions generated in the plasma generation step S22 move in the positive X-axis direction of the film formation chamber 10b, and adhere to the surface of the film formed on the object 11 to be film-formed by the film formation process in the transport chamber 10 a. Further, by applying a positive bias voltage to the object 11, oxygen anions can be more positively attached to the surface of the film formed on the object 11. When the oxygen negative ion generation step S2 is ended as described above, the film formation method shown in fig. 3 is ended.

As described above, according to the film formation device 1 of the present embodiment, since the negative ion generator 24 generates oxygen negative ions in the vacuum chamber 10, the oxygen negative ions can be attached to the surface of the film formed on the object 11 to be film-formed by the film formation process. Accordingly, even when the object 11 to be film-formed after the film formation process is discharged into the atmosphere, oxygen anions adhere to the surface of the film formed on the object 11 to be film-formed, and thus the film quality can be prevented from being lowered due to the adhesion of oxygen in the atmosphere to the surface of the film on the object 11 to be film-formed. As described above, the film quality of the object 11 to be film-formed can be suppressed from decreasing.

According to the film formation device 1 of the present embodiment, since the plasma P is intermittently generated in the vacuum chamber 10, when the generation of the plasma P in the vacuum chamber 10 is stopped, the electron temperature of the plasma P in the vacuum chamber 10 rapidly decreases, and electrons easily adhere to particles of oxygen supplied into the vacuum chamber 10. Thereby, oxygen anions can be efficiently generated in the vacuum chamber 10. As a result, negative ions can be effectively attached to the surface of the film formed on the object 11. As described above, the film quality of the object 11 to be film-formed can be reliably suppressed from decreasing.

According to the film deposition apparatus 1, the plasma P can be generated intermittently easily by merely switching the short-circuit switch SW 1. For example, when the plasma source 7 is a pressure gradient plasma gun, it is difficult to directly stop the generation of the plasma P, but the film formation device 1 according to the present embodiment is preferable because the generation of the plasma P can be easily stopped only by switching the short-circuit switch SW 1.

According to the film formation apparatus 1, the electrons in the film formation chamber 10b can be suppressed from flowing into the transport chamber 10a by the magnetic lines of the sealing magnetic field M generated by the magnetic field generating coil 30, and therefore, the negative ions can be generated more efficiently in the film formation chamber 10 b. As a result, the negative ions can be more effectively attached to the surface of the film formed on the object to be film-formed.

According to the film forming apparatus 1, since the magnetic field generating coil 30 is provided between the film forming chamber 10b and the transporting chamber 10a, the sealing magnetic field M having magnetic lines of force in a direction in which electrons in the film forming chamber 10b are suppressed from flowing into the transporting chamber 10a can be appropriately generated.

According to the film formation device 1, since the plasma source 7 of the film formation section 14 and the plasma source 7 of the negative ion generation section 24 are used in combination, the negative ion generation section 24 can be configured without greatly changing the structure originally provided in the vacuum chamber 10 as a structure necessary for the film formation process. Therefore, the negative ion generating unit 24 can be provided while suppressing influence on the film forming conditions. Further, the apparatus configuration can be simplified by using the plasma source 7 as well.

(embodiment 2)

Next, the structure of a film formation apparatus 1A according to embodiment 2 of the present invention will be described with reference to fig. 4. The film deposition apparatus 1A includes the same elements and configurations as those of the film deposition apparatus 1 according to embodiment 1. Therefore, the same components and configurations as those of the film forming apparatus 1 according to embodiment 1 are denoted by the same reference numerals, and detailed description thereof is omitted, and portions different from embodiment 1 are described.

Fig. 4 is a schematic cross-sectional view showing the structure of the film formation apparatus 1A according to the present embodiment, and is a view showing an operation state in an oxygen anion generation mode. In addition, in the diagram showing the operation state in the film formation processing mode of the film forming apparatus 1A according to embodiment 2, the short-circuit switch SW1 is in the off state, and the diffusion of the film forming material particles Mb into the film forming chamber 10b is different, and the other points are the same, so that the illustration is omitted.

As shown in fig. 4, the film deposition apparatus 1A of the present embodiment is a so-called horizontal film deposition apparatus in which the object 11 to be film deposited is disposed in the vacuum chamber 10 and conveyed so that the direction of the thickness of the object 11 to be film deposited is substantially vertical (Z-axis direction in fig. 4). The film deposition apparatus according to the present embodiment may be the so-called vertical film deposition apparatus. Hereinafter, a horizontal film forming apparatus will be described as an example.

The film forming apparatus 1A includes a vacuum chamber 10, a conveying mechanism 3, a film forming section 14, and a negative ion generating section 24, similarly to the film forming apparatus 1. On the other hand, unlike the film deposition apparatus 1, the film deposition apparatus 1A does not include the magnetic field generating coil 30 and the housing 31 thereof.

In the film forming apparatus 1A, the direction of conveyance of the object 11 is bidirectional instead of unidirectional (arrow B in the figure), and the film forming apparatus 1A is provided with an object holding member 16A (holding member) for holding the object 11 instead of the object holding member 16 for holding the object 11. That is, in the present embodiment, the conveying mechanism 3 conveys the object holding member 16A in the conveying direction (arrow B). The object holding member 16A is, for example, a tray or the like that holds and conveys the object 11 in a state where the surface to be film-formed of the object 11 is exposed. The detailed structure of the object holding member 16A will be described later.

The film forming apparatus 1A is different from the film forming apparatus 1 in that it includes a bias circuit unit 35 for applying a positive bias voltage to the film formation object 11 after film formation, an overhead wire 18 provided in the vacuum chamber 10, a tension applying unit 25 for applying tension to the overhead wire 18, and a load lock chamber 26 (vacuum load lock chamber) disposed adjacent to the vacuum chamber 10. In embodiment 1, the illustration and description of the load lock chamber 26 are omitted, but the film forming apparatus 1 according to embodiment 1 may include the load lock chamber 26. Further, the film formation apparatus 1 according to embodiment 1 may be configured such that the conveyance direction of the object 11 is bidirectional instead of unidirectional.

The bias circuit unit 35 includes a bias power supply 27 (voltage applying unit) for applying a positive bias voltage (hereinafter, simply referred to as "bias voltage") to the object 11, a 3 rd wire 73 for electrically connecting the bias power supply 27 and the overhead wire 18, and a short-circuit switch SW3 provided on the 3 rd wire 73. The bias power supply 27 applies a voltage signal (periodic electric signal) as a rectangular wave that increases or decreases periodically as a bias voltage. The bias power supply 27 is configured to be able to change the frequency of the applied bias voltage by the control of the control unit 50. One end of the 3 rd wire 73 is connected to the positive potential side of the bias power supply 27, and the other end is connected to the pulley 25b of the tension applying portion 25. Thereby, the 3 rd wire 73 is electrically connected to the overhead wire 18 and the bias power supply 27 via the pulley 25 b.

The short-circuit switch SW3 is connected in series between the pulley 25b and the positive potential side of the bias power supply 27 through the 3 rd wiring 73. The short-circuit switch SW3 is a switching unit that switches whether or not a bias voltage is applied to the overhead wire 18. The short-circuit switch SW3 is switched between its on and off states by the control section 50. The short-circuit switch SW3 is turned on at a predetermined timing in the oxygen anion generation mode. When the short switch SW3 is turned on, the overhead wire 18 and the positive potential side of the bias power supply 27 are electrically connected to each other, and a bias voltage is applied to the overhead wire 18.

On the other hand, the short-circuit switch SW3 is turned off at a predetermined timing in the film formation process mode and in the oxygen anion generation mode. When the short-circuit switch SW3 is in the off state, the overhead wire 18 and the bias power supply 27 are electrically disconnected from each other, and no bias voltage is applied to the overhead wire 18. The timing of applying the bias voltage will be described in detail later.

The overhead wire 18 is an overhead wire for supplying power to the film formation object holding member 16A. The overhead wire 18 is in contact with a power supply brush 42, described later, provided in the film formation object holding member 16A, and supplies power to the film formation object holding member 16A through the power supply brush 42. The overhead wire 18 is made of, for example, a stainless steel wire or the like.

The overhead wire 18 extends in the conveyance direction (arrow B) in the conveyance chamber 10 a. One end side of the overhead wire 18 is fixed to the upper end inner wall 10d in the conveyance chamber 10a by an overhead wire fixing portion 28. A tension applying portion 25 is provided on the other end side of the overhead wire 18. The details of the overhead wire fixing unit 28 will be described later.

The tension applying portion 25 includes a pulley support portion 25a fixed to the lower end inner wall 10e in the conveying chamber 10a, a pulley 25b supported by the pulley support portion 25a, and a weight member 25c connected to the other end of the overhead wire 18. The pulley support portion 25a extends from the lower end inner wall 10e toward the upper end inner wall 10d of the conveyance chamber 10a, and is connected to a shaft of the pulley 25 b. The pulley 25B receives the overhead wire 18 and converts the direction of the overhead wire 18 extending in the conveying direction (arrow B) to the negative direction toward the Z axis. The weight member 25c has a predetermined weight, and pulls the overhead wire 18 in the Z-axis negative direction according to the weight. Thereby, tension is applied to the overhead wire 18, and even when the overhead wire 18 expands and contracts due to heat or the like, the overhead wire 18 is not bent.

The load lock chamber 26 is connected to one end of the transport chamber 10a in the transport direction (arrow B) via a shutter 29 that can be opened or closed. The load lock chamber 26 is not limited to one end of the transfer chamber 10a, and may be connected to the other end thereof, or both of the one end and the other end thereof. The load lock chamber 26 controls the vacuum state independently of the transfer chamber 10a and the film forming chamber 10 b. The load lock chamber 26 is configured to carry the object 11 to be film-formed into and out of the transport chamber 10a through a shutter 29.

The load lock chamber 26 carries the object 11 to be film-formed after the film forming process performed by the film forming section 14 from the transfer chamber 10a of the vacuum chamber 10. Thus, the film formation object 11 after the film formation process is accommodated in the load lock chamber 26. In the load lock chamber 26, a power supply terminal portion 51 (see fig. 6 and 8) of the film formation object holding member 16A, which will be described later, is operated. For example, the power supply terminal portion 51 is operated so as to contact the rear surface (the surface on the side on which the film formation process is performed) of the object 11 to be film-formed. By this operation, a bias voltage can be applied to the rear surface of the object 11 to be film-formed by the power supply terminal section 51.

When the above-described operation of the power supply terminal section 51 is performed in the load lock chamber 26 and a bias voltage can be applied to the rear surface of the object 11, the object 11 is carried out to the transport chamber 10a by the load lock chamber 26. For example, the load lock chamber 26 generates negative ions by the negative ion generator 24, and then carries the carried-in object 11 to be film-formed into the transport chamber 10a of the vacuum chamber 10.

Next, the detailed structure of the overhead wire fixing unit 28 will be described with reference to fig. 5. Fig. 5(a) is a schematic front view of the overhead wire fixing part 28, and fig. 5(b) is a schematic side view of the overhead wire fixing part 28. As shown in fig. 5(a) and (b), the overhead wire fixing portion 28 includes a mounting member 32 to be mounted on a peripheral structure (here, the upper end inner wall 10d), a fixing portion 33 to fix the overhead wire 18, and a brush guide portion 37 to guide a power supply brush 42 (see fig. 7 and 9) to the overhead wire 18.

The mounting member 32 is a bracket formed of, for example, an コ -shaped plate member. The mounting member 32 has an upper end fixing portion 32a fixed to an upper end inner wall 10d (see fig. 4) in the conveyance chamber 10a by a bolt 32f or the like, an extending portion 32b extending in the Z-axis negative direction from the upper end fixing portion 32a, and a seat surface portion 32c provided at a front end portion of the extending portion 32b in the Z-axis negative direction.

The fixing portion 33 includes a screw support portion 33a provided at an end portion of the mounting member 32 in the negative direction of the Z-axis direction, a mounting screw 33b protruding from the screw support portion 33a, and a crimp terminal 33c mounted to the mounting screw 33 b. The screw support portion 33a is, for example, a rectangular parallelepiped metal block. The screw support portion 33a is fixed to the extension portion 32b of the mounting member 32 by a bolt 32f or the like via an insulating member 33g made of porcelain or glass. The screw support portion 33a is provided to protrude from the extension portion 32b in the Y-axis positive direction. The mounting screw 33b protrudes from the side surface of the screw support portion 33a in the X-axis positive direction. The crimp terminal 33c is fixed to the mounting screw 33b by a nut 33e or the like. The crimp terminal 33c is connected to one end of the overhead wire 18.

The brush guide portion 37 includes an extension portion 37a extending in the X-axis positive direction from the seat surface portion 32c of the mounting member 32 and a mountain-shaped guide portion 37b curved in the Z-axis positive direction. The extension portion 37a is formed integrally with the seating surface portion 32c of the mounting member 32, and protrudes in the X-axis positive direction from the mounting screw 33b of the fixing portion 33.

The guide portion 37b has a mountain-shaped edge 37e rising in the positive Z-axis direction when viewed from the X-axis direction. The guide portion 37b is widest at a substantially central portion in the Y-axis direction, and the wide portion corresponds to the position of the crimp terminal 33c of the fixing portion 33. The guide portion 37b has a function of guiding the power supply brush 42 of the object holding member 16A to be film-formed, which is carried out from the load lock chamber 26 and carried into the transport chamber 10a, so as to be placed on the overhead wire 18 (see fig. 9).

Next, the detailed structure of the object holding member 16A will be described with reference to fig. 6 to 8. Fig. 6 is a schematic plan view showing the structure of the object holding member 16A shown in fig. 4. Fig. 7 is a sectional view taken along line VII-VII of fig. 6. Fig. 8 is a sectional view taken along line VIII-VIII of fig. 6. Fig. 6 to 8 illustrate a rectangular plate-shaped object 11 to be film-formed. In fig. 6, the back surface 11b (the surface on which the film formation process is performed) of the object 11 is the surface on the back side of the sheet, and the front surface 11a of the object 11 is the surface on the front side of the sheet.

As shown in fig. 6, the object holding member 16A includes a tray 63 and a holder 66 for placing and conveying the object 11. The tray 63 and the holder 66 are made of a conductive metal material such as stainless steel.

The tray 63 is a frame-shaped container on which the holder 66 holding the film formation object 11 is placed. The tray 63 has a base portion 64 on which the holder 66 is placed, and an edge portion 65 rising corresponding to the outer diameter of the holder 66. The base portion 64 protrudes from the inner side surface 65a of the edge portion 65, and supports the back surface (the surface on the rear side of the sheet in fig. 6) side of the holder 66. The base portion 64 has an opening 64c having an outer diameter corresponding to the object 11 to be film-formed in the center.

The holder 66 is a frame-shaped holding portion for holding the film formation object 11. The holder 66 includes a holder body 67, a plurality of claw portions 68 provided on a back surface 67b (a surface on the rear side of the sheet of fig. 6) of the holder body 67, a placement portion 69 provided on the back surface 67b side of the holder body 67 via an insulator 70 (see fig. 7 and 8), and an anti-fouling cover 75 for the insulator 70.

The holder main body portion 67 has a plate shape having a substantially rectangular outer shape, and has an opening portion 67c at a central portion thereof corresponding to the outer shape of the film formation object 11. The holder main body portion 67 has a substantially Y-shaped opening portion 67d at a position corresponding to the power supply terminal portion 51 described later.

The holder main body portion 67 is provided with a power supply brush 42 and a power supply terminal portion 51 as a power supply portion for supplying power from the overhead wire 18. The power supply brush 42 and the power supply terminal portion 51 are formed of a conductive material. The functions and structures of the power supply brush 42 and the power supply terminal portion 51 will be described in detail later with reference to fig. 7 to 10.

In the present embodiment, two power supply brushes 42 and two power supply terminal portions 51 are provided at point-symmetrical positions, respectively, in a plan view. Thus, even when the film formation object 11 is conveyed in a state where the holder 66 is rotated by 180 degrees, power can be supplied from the overhead wire 18 to the power supply brushes 42 and the power supply terminal portions 51. Further, the film formation object 11 may be located at a position where it can be brought into contact with any one of the two power feeding terminal portions 51 arranged to be offset in point symmetry, and therefore, the degree of freedom in the size and position of the film formation object 11 on the holder 66 can be increased.

The claw portion 68 protrudes more inward than the opening portion 67c in a plan view, and has a portion exposed without overlapping the holder body portion 67. The claw portion 68 supports the rear surface 11b of the object 11 at the exposed portion. In addition, since the portion of the rear surface 11b of the object 11 to be film-formed supported by the claw portion 68 overlaps the claw portion 68, the film is not formed after the film forming process. That is, since the claw portions 68 are insulated from the rear surface 11b of the object 11, even when a bias voltage is applied to the holder body portion 67, no power is supplied from the claw portions 68 to the rear surface 11b of the object 11.

As shown in fig. 7 and 8, the placement portion 69 is placed on the base portion 64 of the tray 63. The mount portion 69 is fixed to the rear surface 67b side of the holder body portion 67 by a bolt 69f or the like. The mount portion 69 is fixed apart from the rear surface 67b side of the holder body portion 67, and does not contact the rear surface 67b of the holder body portion 67.

An insulator 70 is provided between the mounting portion 69 and the bolt 69f, and the mounting portion 69 is electrically insulated from the holder body portion 67. The insulator 70 is made of an insulating material such as porcelain or glass. The placement portion 69 electrically insulated from the holder body portion 67 is sandwiched between the holder body portion 67 and the tray 63, whereby the tray 63 is electrically insulated from the holder body portion 67. Accordingly, even when a bias voltage is applied to the holder body portion 67, the tray 63 is electrically insulated.

The cover 75 protects the insulator 70 during film formation so that the conductive film does not adhere to the insulator 70. The cover 75 includes a cylindrical member 75a and a circular plate member 75 b. The cylindrical member 75a does not contact the back surface 67b of the holder body 67, and surrounds the insulator 70 between the back surface 67b of the holder body 67 and the placement portion 69. The disk member 75b is provided at the lower end (end in the Z-axis negative direction) of the insulator 70, and covers the entire lower end. In this way, the insulator 70 is protected by the cover 75, and as a result, a decrease in insulation of the insulator 70 can be suppressed.

Next, the configurations of the power supply brush 42 and the power supply terminal portion 51 will be described in detail.

The power supply brush 42 supplies power from the overhead wire 18 to the holder body portion 67 by contacting the overhead wire 18 to which the bias voltage is applied. That is, the power supply brush 42 has a function of applying a bias voltage from the overhead wire 18 to the holder body portion 67. As described above, even when a bias voltage is applied to the holder body portion 67, no power is supplied from the claw portion 68 to the rear surface 11b of the film formation object 11. Therefore, the power supply terminal portion 51 is brought into contact with the rear surface 11b of the object 11 to be film-formed, and thereby supplies power from the holder main body portion 67 to the rear surface 11b of the object 11 to be film-formed. That is, the power supply terminal portion 51 has a function of applying a bias voltage from the holder main body portion 67 to the rear surface 11b of the object 11 to be film-formed. Hereinafter, each configuration of the power supply brush 42 and the power supply terminal portion 51 will be described in more detail.

First, the power supply brush 42 will be described with reference to fig. 6, 7, and 9. As shown in fig. 6 and 7, the power supply brush 42 includes a plate-shaped brush body 43, a brush shaft portion 44 supporting the brush body 43, a shaft support portion 45 supporting the brush shaft portion 44, and a brush fixing portion 46 fixing the shaft support portion 45 to a surface 67a of the holder main body portion 67.

The brush body 43 is substantially rectangular, and the thickness direction thereof is along the Y-axis direction. One end side of the brush body 43 in the longitudinal direction becomes a free end, and a circular base end portion 43d is formed on the other end side in the longitudinal direction. The base end portion 43d is rotatably supported by a brush shaft portion 44 extending in the Y axis direction via a coupling shaft portion and the like, not shown. That is, the brush body 43 is rotatable about the brush shaft portion 44, and the free end of the brush body 43 is movable in the direction along the Z-axis direction (arrow C in fig. 7) in a state where the brush body 43 extends in the X-axis direction. The edge 43e of the brush body 43 is placed on the overhead wire 18 extending in the Y-axis direction. Thereby, the brush body 43 contacts the overhead wire 18. As a result, power is supplied from the overhead wire 18 to the holder body portion 67 through the brush 43.

The brush body 43 is guided by the brush guide portion 37 to be placed on the overhead wire 18. Fig. 9 is a diagram illustrating an operation of the brush body 43 guided by the brush guide portion 37. As shown in fig. 9, when the film formation object holding member 16A is conveyed, the brush body 43 moves on the guide portion 37b of the brush guide portion 37 in the Y-axis direction, which is the conveying direction. At this time, the edge 43e of the brush body 43 is in contact with the edge 37e of the guide portion 37 b. Thereby, the brush body 43 is moved in the Y-axis direction so as to straddle the crimp terminal 33d, and is placed on the overhead wire 18 connected to the crimp terminal 33d, and the brush body 43 is brought into contact with the overhead wire 18.

Referring again to fig. 6 and 7, the brush shaft portion 44 extends in the Y-axis direction, and one end and the other end thereof are fixed to the shaft support portion 45. The shaft support portions 45 are located at one end and the other end of the brush shaft portion 44. The shaft support portion 45 is a substantially L-shaped plate member, and includes a side surface portion 45a extending in the Z-axis direction and a bottom surface portion 45b extending in the X-axis direction and the Y-axis direction. The side surface portion 45a is fixed to the brush shaft portion 44, and the bottom surface portion 45b is fixed to the disk brush fixing portion 46.

The disk brush fixing portion 46 is disposed between the shaft support portion 45 and the holder main body portion 67. The disk brush fixing portion 46 is a substantially L-shaped plate member, and has a side surface portion 46a extending in the Z-axis direction and a bottom surface portion 46b extending in the Z-axis direction and the Y-axis direction. The side surface portion 46a can receive the edge 43e of the brush 43 so as not to rotate the brush 43 more in the Z-axis negative direction than the holder main body portion 67. The bottom surface portion 46b is fixed to the bottom surface portion 45b of the shaft support portion 45 and the surface 67a of the holder main body portion 67.

Next, the power supply terminal unit 51 will be described with reference to fig. 8 and 10. Fig. 10 is a diagram illustrating an operation of the power supply terminal unit 51. Fig. 10(a) is an enlarged view of the power supply terminal unit 51 of fig. 6, and fig. 10(b) is a cross-sectional view taken along the line b-b of fig. 10 (a).

As shown in fig. 8 and 10, the power supply terminal portion 51 includes the lead terminal 52 which can be brought into contact with the rear surface 11b of the object 11 to be film-formed, a lead shaft portion 56 which supports the lead terminal 52, a shaft supporting portion 57 which supports the lead shaft portion 56, and a rotation restricting portion 58 which restricts rotation of the lead terminal 52.

The lead terminal 52 is rotatably supported by a lead shaft portion 56 extending in the Y-axis direction via a joint portion or the like, not shown. That is, the lead terminal 52 can rotate around the lead shaft portion 56.

The lead terminal 52 is formed by bending a plate-like member, and has an abutting portion 53 abutting against the rotation restricting portion 58, a bent portion 54 bent in a V-shape from the abutting portion 53, and a tip end protruding portion 55 bent from the bent portion 54 toward a side opposite to a direction in which the bent portion 54 is bent.

The rear surface 53b of the contact portion 53 is supported by the rotation restricting portion 58 by contacting the front surface 58a of the rotation restricting portion 58. This restricts rotation of the lead terminal 52 around the lead shaft portion 56. A weight member 53c is joined to a surface 53a of the abutment portion 53.

The bent portion 54 is bent in the Z-axis negative direction from the contact portion 53 in a state where the contact portion 53 is supported by the rotation restricting portion 58, that is, in a state where the contact portion 53 extends in the X-axis direction. The bent portion 54 extends at an obtuse angle with respect to the abutting portion 53. The distal end projection 55 is bent in the Z-axis positive direction from the bent portion 54 in a state where the contact portion 53 is supported by the rotation restricting portion 58, that is, in a state where the contact portion 53 extends in the X-axis direction. The distal end protrusion 55 extends toward the rear surface 11b of the object 11 to be film-formed at a substantially right angle to the bent portion 54. The front end projections 55 can contact the rear surface 11b of the object 11 to be film-formed by rotating the lead terminals 52.

The lead shaft portion 56 extends in the Y-axis direction, and one end and the other end thereof are fixed to the shaft support portion 57. The shaft support portions 57 are located at one end and the other end of the lead shaft portion 56. The shaft support portion 57 is a substantially L-shaped plate member, and has a side surface portion 57a extending in the Z-axis direction and a bottom surface portion 57b extending in the X-axis direction and the Y-axis direction. The side surface portion 57a hangs down from the opening portion 67d of the holder body portion 67 toward the rear surface 67b of the holder body portion 67, and is fixed to the lead shaft portion 56. The bottom surface portion 57b is fixed to the surface 67a of the holder body portion 67.

The rotation restricting portion 58 is a substantially rectangular plate-like member, and is provided on the back surface 67b of the holder main body portion 67. The rotation restricting portion 58 is supported by a bolt 58f or the like so as to be rotatable along the back surface 67b of the holder main body portion 67.

Specifically, the rotation restricting portion 58 is rotatable from a position supporting the lead terminal 52 indicated by a solid line to an arrow E direction shown in fig. 10(a), and is movable to a position indicated by a two-dot chain line. When the rotation restricting portion 58 is rotated in the direction of the arrow E shown in fig. 10(a), the front surface 58a of the rotation restricting portion 58 does not abut on the rear surface 53b of the abutting portion 53. Thereby, the rotation restriction of the lead terminal 52 by the rotation restricting portion 58 is released, and the lead terminal 52 is rotated in the arrow D direction shown in fig. 10(b) by the weight of the weight member 53c or the like. Then, the lead terminals 52 are moved from the positions indicated by the solid lines to the positions indicated by the two-dot chain lines, and the front end projections 55 of the lead terminals 52 are brought into contact with the rear surface 11b of the object 11 to be film-formed. As a result, power is supplied from the holder body 67 to the rear surface 11b of the object 11 to be film-formed through the distal end protrusion 55.

The rotation restricting unit 58 is provided with an operation unit 58d for operating the rotational movement. The operation portion 58d is formed of, for example, a bolt, and protrudes from the back surface 58b side of the rotation restricting portion 58 toward the front surface 58a side to the front surface 58a side. As described above, the operation of the power supply terminal section 51 is performed at the time when the film formation object holding member 16A is carried into the load lock chamber 26. That is, the operation portion 58d of the power supply terminal portion 51 is operated in the load lock chamber 26 so that the power supply terminal portion 51 is brought into contact with the rear surface 11b of the object 11 to be film-formed. The operation unit 58d is operated by, for example, an actuator (not shown) or the like that operates when a predetermined operation condition is satisfied. The operation of the operation unit 58d is not limited to the operation by an actuator or the like, and may be any other operation method including manual operation.

Next, a suitable timing for applying the bias voltage to the object 11 to be film-formed will be described with reference to fig. 11. The timing of applying the bias voltage to the object 11 is not limited to the timing described below, and the bias voltage may be applied at any timing in the negative ion generation mode, for example.

Fig. 11 is a graph showing a temporal change in the flux of ions present in the vacuum chamber 10. The horizontal axis of fig. 11 represents the processing time [ sec ] in the oxygen anion generation mode, and the vertical axis of fig. 11 represents the flux intensity [ a.u ] of the ions in the vacuum chamber 10. The curve G1 is a curve showing a temporal change in the flux of argon positive ions, the curve G2 is a curve showing a temporal change in the flux of oxygen positive ions, and the curve G3 is a curve showing a temporal change in the flux of oxygen negative ions. In fig. 11, a period T1 indicates a period during which the generation of the plasma P is performed, and a period T2 indicates a period during which the generation of the plasma P is stopped. That is, fig. 11 shows the relationship between the time when the plasma P is generated and the ions present in the vacuum chamber 10.

As shown in fig. 11, the period T1 during which the plasma P is generated and the period T2 during which the generation of the plasma P is stopped are repeated, and the plasma P is intermittently generated. After the generation of the plasma P is stopped, a large amount of argon positive ions and oxygen positive ions and corresponding electrons are present for about 0.001 to 0.0015 seconds. After about 0.002 seconds or so after the generation of the plasma P is stopped, the argon positive ions and the oxygen positive ions disappear, the electrons disappear, and the ratio of the oxygen negative ions increases.

Therefore, in the film formation device 1A according to the present embodiment, after the generation of the plasma P by the negative ion generator 24 is stopped, the bias voltage is applied to the object 11 to be film-formed. For example, in the oxygen anion generation mode, the bias power supply 27 applies a bias voltage to the object 11 to be film-formed at a time after several milliseconds have elapsed after the generation of the plasma P is stopped. More specifically, while plasma P is being generated, control unit 50 turns short-circuit switch SW3 off, and after several milliseconds have elapsed since plasma P was stopped, control unit 50 turns short-circuit switch SW3 on. When the short switch SW3 is turned on, the overhead wire 18 and the bias power supply 27 are electrically connected to each other, and a bias voltage is applied to the overhead wire 18.

Then, power is supplied from the overhead wire 18 to the holder body portion 67 through the brush 43, and power is supplied from the holder body portion 67 to the rear surface 11b of the object 11 to be film-formed through the tip end protrusion portion 55. As a result of the positive bias voltage being applied to the rear surface 11b of the object 11, the oxygen anions generated in the oxygen anion generation mode are attracted to the rear surface 11b of the object 11.

In particular, in the present embodiment, after the generation of the plasma P is stopped, the bias voltage is applied to the object 11 at a timing when the oxygen anions are greatly increased after several milliseconds have elapsed. As a result, a large amount of oxygen anions are attracted to the rear surface 11b side of the object 11 to be film-formed, and are irradiated to the film formed on the object 11 to be film-formed.

The application of the bias voltage to the object 11 is continued until the next generation of the plasma P by the negative ion generator 24 is started. Specifically, before the next plasma generation in the negative ion generating unit 24 is started, the short-circuit switch SW3 is turned off by the control unit 50, and the overhead wire 18 and the bias power supply 27 are not electrically connected to each other. In this way, the timing of applying the bias voltage to the object 11 is alternately repeated with the plasma P generation period in the negative ion generation mode.

Next, referring to fig. 12 to 14, an effect produced by applying a bias voltage to the object 11 to be film-formed after the film formation process and irradiating it with oxygen anions will be described.

First, the effect of the oxygen negative ion irradiation on the electrical characteristics of the film formed on the object 11 to be film-formed will be described with reference to fig. 12 and 13. Fig. 12 is a graph showing a relationship between the presence or absence of irradiation of oxygen anions and carrier density. The horizontal axis of FIG. 12 represents the Oxygen Flow Rate (OXygen Flow Rate: OFR) [ sccm ]]The vertical axis of FIG. 12 represents the carrier density [ cm ]^-3]. A curve G4 in fig. 12 is a curve showing the carrier density according to the oxygen gas flow rate when the object 11 to be film-formed is irradiated with oxygen anions in the oxygen anion generation mode. A curve G5 in fig. 12 is a curve showing the carrier density according to the oxygen gas flow rate when the object 11 to be film-formed is not irradiated with oxygen anions in the oxygen anion generation mode.

Fig. 13 is a graph showing a relationship between the presence or absence of irradiation with oxygen anions and optical mobility. FIG. 1 shows a schematic view of aThe horizontal axis of 3 represents the oxygen flow rate [ sccm ]]The vertical axis of FIG. 13 represents optical mobility (. mu.opt) [ cm ]²/Vs]. A curve G6 in fig. 13 is a curve showing the optical mobility according to the oxygen gas flow rate when the object 11 to be film-formed is irradiated with oxygen anions in the oxygen anion generation mode. A curve G7 in fig. 13 is a curve showing the optical mobility according to the oxygen gas flow rate when the object 11 to be film-formed is not irradiated with oxygen anions in the oxygen anion generation mode. The optical mobility is measured by mobility in the grains of the object 11 to be film-formed.

As the film formation conditions in the film formation processing mode, a ZnO film having Ga of 4.0 wt% and a thickness of 50nm was formed on the object 11 to be film-formed by setting the current value to 150A and the oxygen flow rate to 10sccm, 15sccm, 20sccm, or 25 sccm. As the conditions for the irradiation of oxygen anions in the oxygen anion generation mode, a bias voltage of 15V having a frequency of 60Hz and a rectangular wave was applied to the object 11 for 10 minutes with a discharge current value of 12A and an oxygen flow rate of 10 sccm.

As shown in fig. 12, with respect to all the oxygen gas flow rates, when oxygen anions are irradiated to the object 11, the carrier density decreases compared to when oxygen anions are not irradiated to the object 11. Specifically, a decrease in carrier density of about 20% was observed at oxygen flow rates of 10sccm, 15sccm, and 20sccm, and a decrease in carrier density of about 7% was observed at oxygen flow rates of 25 sccm. The decrease in carrier density indicates that carriers (electrons) are trapped by grain boundaries, impurities, or the like, or that oxygen vacancies decrease.

As shown in fig. 13, when oxygen anions are irradiated to the object 11, the optical mobility increases compared to when oxygen anions are not irradiated to the object 11 with respect to all the oxygen gas flow rates. An increase in optical mobility indicates a decrease in oxygen vacancies within the crystal and an increase in intra-granular mobility. As a result, the carrier density is reduced. As described above, it was confirmed that the film formed on the object 11 after film formation was modified by irradiation with oxygen anions.

Accordingly, by irradiating the object 11 after the film formation process with oxygen anions, the film can be modified by adjusting the object 11 to reduce oxygen vacancies in the film. Therefore, even when the object 11 to be film-formed with a film is discharged into the atmosphere, oxygen in the atmosphere can be inhibited from adhering to the surface of the film on the object 11 to be film-formed, and the film quality can be further inhibited from decreasing.

Next, referring to fig. 14, the effect of the oxygen anion irradiation on the characteristics of the hydrogen sensor when the film on the object 11 to be film-formed is used as the hydrogen sensor will be described. Fig. 14 is a graph showing a relationship between the presence or absence of irradiation of oxygen anions and the characteristics of the hydrogen sensor. The horizontal axis of fig. 14 represents the response time sec of the hydrogen sensor, and the vertical axis of fig. 14 represents the current value a flowing through the hydrogen sensor. Fig. 14(a) is a graph showing the current value with respect to the response time of the hydrogen sensor when the object 11 to be film-formed is irradiated with oxygen anions in the oxygen anion generation mode. Fig. 14(b) is a graph showing the current value with respect to the response time of the hydrogen gas sensor when no oxygen anions are irradiated to the object 11 to be film-formed in the oxygen anion generation mode.

As shown in fig. 14(b), when the object 11 to be film-formed is not irradiated with oxygen anions, the ground level of the current value of the hydrogen sensor is unstable, and the operation of the hydrogen sensor is unstable. On the other hand, as shown in fig. 14(a), it was confirmed that when the object 11 to be film-formed was irradiated with oxygen anions, the ground level of the current value of the hydrogen sensor was stable, and the operation stability of the hydrogen sensor was improved.

As described above, according to the film formation device 1A of the present embodiment, the bias power supply 27 applies a positive bias voltage to the object 11 to be film-formed after the film formation process. Thereby, the oxygen anions generated in the anion generator 24 are attracted to the object 11 and irradiated on the surface of the film formed on the object 11. As a result, the film quality can be prevented from being lowered due to the adhesion of oxygen in the atmosphere to the surface of the film on the object 11.

Further, according to the film deposition apparatus 1A of the present embodiment, the power supply brush 42 and the power supply terminal portion 51 provided in the film deposition object holding member 16A that holds the film deposition object 11 are supplied with power from the overhead wire 18 provided in the vacuum chamber 10. This makes it possible to easily apply a positive voltage to the object 11 through the power supply brush 42 and the power supply terminal portion 51 of the object holding member 16A.

In the film deposition apparatus 1A according to the present embodiment, the tension applying unit 25 applies tension to the overhead wire 18. This can suppress the deflection even when the overhead wire 18 expands and contracts due to heat or the like generated in the vacuum chamber 10.

Then, the oxygen anions present in the vacuum chamber 10 increase after the generation of the plasma P by the anion generator 24 is stopped. According to the film formation device 1A of the present embodiment, the positive bias voltage is applied to the object 11 to be film-formed at the timing when the oxygen anions increase after the generation of the plasma P is stopped. Thereby, the object 11 to be film-formed is irradiated with a large amount of oxygen anions. As a result, the film quality degradation due to the adhesion of oxygen in the atmosphere to the surface of the film on the object 11 to be film-formed can be further suppressed.

Further, according to the film deposition apparatus 1A of the present embodiment, the object 11 to be film-deposited after the film deposition process is carried into the load-lock chamber 26 from the transport chamber 10a of the vacuum chamber 10, and the carried-in object 11 to be film-deposited is carried out from the load-lock chamber 26 to the transport chamber 10a of the vacuum chamber 10 after the negative ion generator 24 generates oxygen negative ions. Thus, the object 11 to be film-formed is carried into the transport chamber 10a at an appropriate timing for generating oxygen anions without being exposed to the atmosphere. As a result, the object 11 to be film-formed can be appropriately irradiated with oxygen anions.

While one embodiment of the present embodiment has been described above, the present invention is not limited to the above embodiment, and may be modified and applied to other embodiments without departing from the spirit of the invention described in the claims.

For example, although the plasma source 7 is a pressure gradient plasma gun in the above embodiment, the plasma source 7 is not limited to a pressure gradient plasma gun as long as it can generate plasma in the vacuum chamber 10.

In the above embodiment, the plasma is intermittently generated when the negative ions are generated, but the present invention is not limited to this. For example, when negative ions are generated, a current can be stably supplied to the 2 nd intermediate electrode 62, and a stable discharge can be generated.

In the above embodiment, only one set of the plasma source 7 and the crucible mechanism 2 is provided in the vacuum chamber 10, but a plurality of sets may be provided. Also, the plasma P may be supplied from a plurality of plasma sources 7 for one material. In the above embodiment, the annular hearth 6 is provided, but the annular hearth 6 may be omitted by designing the direction of the plasma source 7 and the position or direction of the material in the hearth mechanism 2.

The steering coil 5 is not necessarily excited in the oxygen anion generation mode.

In the film forming method shown in fig. 3, the raw material gas supply step S21, the plasma generation step S22, and the sealing magnetic field formation step S23 included in the negative ion generation step S2 do not necessarily have to be performed in this order, and the processes of S21 to S23 may be performed simultaneously. In the film forming step S1, the film forming step S1 may be ended before the film forming process is completely ended, and the process may proceed to the negative ion generating step S2.

The film deposition apparatus 1, 1A may include, for example, an opposing coil disposed at a position opposing the plasma source 7 (for example, on the side wall 10i side of the film deposition chamber 10b) outside the vacuum chamber 10. In this case, a magnetic field extending in a direction from the plasma source 7 toward the opposing coil may be formed in the vacuum chamber 10. When such a magnetic field is formed, electrons of the plasma P in the vacuum chamber 10 are bound by the magnetic field, and the electrons are inhibited from flowing into the object 11. This makes it possible to easily diffuse the negative ions generated in the vacuum chamber 10 toward the object 11 and to effectively attach the negative ions to the surface of the film formed on the object 11.

The film forming apparatuses 1 and 1A may include, for example, a counter electrode disposed on an inner wall 10k of the side wall 10i of the film forming chamber 10b and functioning as an anode. The opposing electrode converges the magnetic field formed in the vacuum chamber 10 when the opposing coil is provided. Then, the electrons of the plasma P are appropriately retained along the magnetic field thus converged, and the flow of the electrons into the object 11 to be film-formed can be further suppressed. This makes it possible to further diffuse the oxygen anions generated in the vacuum chamber 10 toward the object to be film-formed 11 with ease, and to more effectively attach the oxygen anions to the surface of the film formed on the object to be film-formed.

The film formation apparatuses 1 and 1A according to the above embodiments are apparatuses for performing film formation by an ion plating method, but are not limited thereto. For example, sputtering, chemical vapor deposition, or the like can be used.

The film formation device 1A according to embodiment 2 does not include the magnetic field generating coil 30 and the housing 31 thereof, but is not limited thereto, and may include the magnetic field generating coil 30 and the housing 31 thereof.

In the above embodiment, the object 11 is irradiated with oxygen anions by applying a bias voltage to the object 11, but the present invention is not limited thereto. For example, a bias voltage can be applied to the object 11 when depositing (forming) the film forming material particles Mb on the object 11. In this case, by applying a negative bias voltage to the object 11 to be film-formed and charging the object 11 negatively, it is possible to suppress the entry of electrons present in the film-forming chamber 10b to the transport chamber 10a side and to promote the entry of the ionized particles Mb of the film-forming material present in the film-forming chamber 10b to the transport chamber 10a side.

Description of the symbols

1-film forming apparatus, 7-plasma source (plasma gun), 10-vacuum chamber, 10 a-transport chamber, 10 b-film forming chamber, 11-film forming object, 14-film forming section, 16A-film forming object holding member, 18-overhead line, 24-negative ion generating section, 25-tension imparting section, 26-load lock chamber (vacuum load lock chamber), 27-bias power supply (voltage applying section), 30-magnetic field generating coil, 40-raw material gas supplying section, 42-power supply brush (power supplying section), 50-control section, 51-power supply terminal section (power supplying section), Ma-film forming material, Mb-film forming material particles, P-plasma, SW 1-short circuit switch (switching section), M-sealing magnetic field.

Claims

1. An anion generator for irradiating an object with anions, comprising:

a plasma source for supplying plasma into the vacuum chamber; and

a unit for lowering an electron temperature of the plasma in the vacuum chamber.

2. The negative ion generation device according to claim 1,

the means for lowering the electron temperature of the plasma in the vacuum chamber has a control unit that controls the plasma to be supplied intermittently into the vacuum chamber.

3. The negative ion generating apparatus according to claim 2,

the negative ion generating device further includes a switching unit that switches between supply and cutoff of the plasma into the vacuum chamber,

the control unit intermittently supplies the plasma by switching the switching unit.

4. The negative ion generating apparatus according to any one of claims 1 to 3,

the vacuum chamber has a negative ion generation chamber (10b) for supplying plasma to a raw material of negative ions to attach electrons to the raw material, and a transport chamber for transporting the object,

the negative ion generating device further includes a magnetic field generating coil that suppresses an electron in the negative ion generating chamber from flowing into the transport chamber during the process of generating negative ions in the negative ion generating chamber.

5. The negative ion generation device according to claim 4,

the magnetic field generating coil forms a sealed magnetic field having magnetic lines of force extending in a direction intersecting a direction from the negative ion generating chamber toward the conveying chamber within the vacuum chamber.

6. The negative ion generating apparatus according to any one of claims 1 to 5,

the plasma source is a pressure gradient type plasma gun.

7. An anion generator for irradiating an object with anions,

comprises a plasma source for supplying plasma into a vacuum chamber,

the plasma source is a pressure gradient type plasma gun having an electrode for converging plasma, and is provided with a switching unit for switching the ease of flow of current to the electrode.