阅读说明：本技术 负离子生成装置 (Negative ion generating device ) 是由 北见尚久 前原诚 木下公男 于 2021-03-17 设计创作，主要内容包括：本发明提供一种负离子生成装置,能够抑制对于对象物的损伤。负离子生成装置(1)在负离子生成部(4)与对象物配置部(3)之间设置有抑制对于对象物配置部(3)的紫外光(UV)的紫外光抑制机构(60)。在负离子生成部(4)为了生成负离子而生成等离子体(P)的情况下,包含紫外光(UV)的等离子体光朝向配置于对象物配置部(3)的基板(11)的方向。此时,通过紫外光抑制机构(60)抑制对于基板(11)的紫外光(UV),能够减少或阻断照射到基板(11)上的紫外光(UV)。(The invention provides a negative ion generating device which can inhibit damage to an object. The negative ion generating device (1) is provided with an ultraviolet light suppressing mechanism (60) for suppressing ultraviolet light (UV) with respect to the object arrangement part (3) between the negative ion generating part (4) and the object arrangement part (3). When the negative ion generating unit (4) generates plasma (P) for generating negative ions, plasma light including ultraviolet light (UV) is directed toward the substrate (11) disposed on the object disposition unit (3). In this case, the ultraviolet light (UV) applied to the substrate (11) is suppressed by the ultraviolet light suppressing mechanism (60), and the ultraviolet light (UV) applied to the substrate (11) can be reduced or blocked.)

1. An anion generating apparatus that generates anions and irradiates the anions to an object, the anion generating apparatus comprising:

a chamber in which the generation of negative ions is performed;

a negative ion generator configured to generate the negative ions by generating plasma in the chamber;

an object arrangement unit configured to arrange the object; and

and an ultraviolet light suppressing mechanism for suppressing ultraviolet light to the object arrangement portion between the negative ion generating unit and the object arrangement portion.

2. The negative ion generating apparatus according to claim 1,

the ultraviolet light suppressing mechanism includes a member disposed between the negative ion generating unit and the object disposing unit in the chamber and configured to suppress the ultraviolet light from passing therethrough.

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

the member inhibits the passage of the ultraviolet light and allows the passage of the negative ions.

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

the ultraviolet light suppressing mechanism includes a switching unit that switches the position of the member between a timing when the plasma is generated by the negative ion generating unit and a timing when the plasma is stopped.

5. The negative ion generation device according to any one of claims 1 to 4,

the ultraviolet light suppressing mechanism is configured by the chamber which blocks the ultraviolet light by a wall portion between the negative ion generating portion and the object disposing portion.

Technical Field

The present application claims priority based on japanese patent application No. 2020-. The entire contents of this Japanese application are incorporated by reference into this specification.

The present invention relates to an anion generating apparatus.

Background

Conventionally, as an anion generator, an anion generator described in patent document 1 is known. The negative ion generating device is provided with: a gas supply unit configured to supply a gas serving as a raw material of negative ions into the chamber; and a negative ion generating unit that generates negative ions by generating plasma in the chamber. The negative ion generator generates negative ions in the chamber by plasma, and irradiates the object with the negative ions.

Patent document 1: japanese patent laid-open publication No. 2017-025407

In the negative ion generating device described above, when the negative ion generating unit generates plasma, the plasma light includes ultraviolet light. At this time, the object irradiated with the negative ions is irradiated with ultraviolet light, and thus the object may be damaged.

Disclosure of Invention

Accordingly, an object of the present invention is to provide a negative ion generator capable of suppressing damage to an object.

In order to solve the above problem, an anion generator according to the present invention generates anions and irradiates the anions to an object, and includes: a chamber in which negative ions are generated; a negative ion generating unit for generating negative ions by generating plasma in the chamber; an object arrangement unit for arranging an object; and an ultraviolet light suppressing mechanism for suppressing ultraviolet light to the object arrangement portion between the negative ion generating portion and the object arrangement portion.

The negative ion generating device according to the present invention includes an ultraviolet light suppressing mechanism for suppressing ultraviolet light with respect to the object arrangement portion between the negative ion generating portion and the object arrangement portion. When the negative ion generating unit generates plasma for generating negative ions, plasma light including ultraviolet light is directed toward the object disposed in the object disposing unit. In this case, the ultraviolet light suppressing means suppresses the ultraviolet light with respect to the object, thereby reducing or blocking the ultraviolet light irradiated to the object. With this, damage to the object can be suppressed.

The ultraviolet light suppressing mechanism may include a member that is disposed between the ion generating unit and the object disposing unit in the chamber and suppresses transmission of ultraviolet light. In this case, ultraviolet light can be suppressed from being applied to the object by merely adding a member to the existing chamber without changing the shape of the entire chamber.

The member may inhibit the passage of ultraviolet light and allow the passage of negative ions. In this case, the ultraviolet light can be suppressed from being applied to the object without providing a mechanism for moving the member.

The ultraviolet light suppressing mechanism may have a switching portion that switches the position of the member between a timing when the plasma is generated by the negative ion generating portion and a timing when the plasma is stopped. In this case, the switching unit can block the ultraviolet light to the object by disposing the member between the negative ion generating unit and the object at the time when the plasma is being generated. On the other hand, when the plasma is stopped, the switching unit removes the member, and thereby the negative ions generated by the negative ion generating unit can be irradiated to the object.

The ultraviolet light suppressing mechanism may be constituted by a chamber that blocks ultraviolet light by a wall portion between the negative ion generating portion and the object disposing portion. In this case, ultraviolet light can be suppressed with respect to the object without adding a separate member.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to provide a negative ion generator capable of suppressing damage to an object.

Drawings

Fig. 1 is a schematic cross-sectional view showing the structure of a negative ion generator according to the present embodiment.

Fig. 2 is a graph showing the timing of turning on/off the plasma P and the state of the positive ions and negative ions flying toward the object.

Fig. 3 is a schematic view showing an example of the aperture ratio adjusting member.

Fig. 4 is a schematic cross-sectional view showing the structure of a negative ion generator according to a modification.

Fig. 5 is a schematic cross-sectional view showing the structure of a negative ion generator according to a modification.

Fig. 6 is a schematic cross-sectional view showing the structure of a negative ion generator according to a modification.

Fig. 7 is a schematic enlarged view showing a structure around a substrate of the negative ion generator according to the modification.

Description of the symbols

1-negative ion generating device, 2-chamber, 3-object arrangement part, 4-negative ion generating part, 11-substrate (object), 60-ultraviolet light suppressing mechanism, 61A, 61B, 63A, 63B-aperture ratio adjusting part (part), 66-opening/closing part (part), 67-switching part, 102-chamber (ultraviolet light suppressing mechanism).

Detailed Description

Hereinafter, an anion generator 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.

First, the structure of the negative ion generator according to the embodiment of the present invention will be described with reference to fig. 1. Fig. 1 is a schematic cross-sectional view showing the structure of a negative ion generator according to the present embodiment. For convenience of explanation, fig. 1 shows an XYZ coordinate system. The X-axis direction is a thickness direction of the substrate as the object. The Y-axis direction and the Z-axis direction are orthogonal to the X-axis direction and to each other.

As shown in fig. 1, the negative ion generating device 1 of the present embodiment includes a chamber 2, an object arranging unit 3, a negative ion generating unit 4, a gas supplying unit 6, a circuit unit 7, a voltage applying unit 8, and a control unit 50.

The chamber 2 is a member for accommodating the substrate 11 (object) and performing irradiation processing of negative ions. The chamber 2 is a member in which negative ions are generated. The chamber 2 is made of a conductive material and is connected to a ground potential.

The chamber 2 includes a pair of walls 2a and 2b facing each other in the X-axis direction, a pair of walls 2c and 2d facing each other in the Y-axis direction, and a pair of walls (not shown) facing each other in the Z-axis direction. Wall 2a is disposed on the negative side and wall 2b is disposed on the positive side in the X-axis direction. Wall portion 2c is disposed on the negative side in the Y-axis direction, and wall portion 2d is disposed on the positive side.

The object arrangement unit 3 is used to arrange a substrate 11 as an irradiation object of negative ions. The object arrangement portion 3 is provided in the wall portion 2a of the chamber 2. The object arrangement unit 3 includes a placement member 12 and a connection member 13. The mounting member 12 and the connecting member 13 are made of a conductive material. The mounting member 12 is a member for mounting the substrate 11 on the mounting surface 12 a. The mounting member 12 is attached to the wall portion 2a and disposed in the internal space of the chamber 2. The mounting surface 12a is a plane that is developed so as to be orthogonal to the X-axis direction. Thus, the substrate 11 is mounted on the mounting surface 12a so as to be orthogonal to the X-axis direction and so as to be parallel to the ZY plane. The connecting member 13 is a member for electrically connecting the mounting member 12 and the voltage applying unit 8. The connecting part 13 extends through the wall part 2a to the outside of the chamber 2. The positional relationship of the connecting member 13 may be any positional relationship as long as it does not interfere with the plasma gun 14 and the anode 16 as the negative ion generating unit 4.

As the substrate 11 to be irradiated with negative ions, for example, ITO, IWO, ZnO, Ga are formed on the surface of a base material₂O₃And films of AlN, GaN, SiON, etc. As the base material, for example, a plate-like member such as a glass substrate or a plastic substrate is used.

Next, the structure of the negative ion generator 4 will be described in detail. The negative ion generator 4 generates plasma and electrons in the chamber 2, thereby generating negative ions, radicals, and the like. The negative ion generator 4 includes a plasma gun 14 and an anode 16.

The plasma gun 14 is, for example, a pressure gradient type plasma gun, and has a main body portion provided on the wall portion 2c of the chamber 2 and connected to the internal space of the chamber 2. The plasma gun 14 generates plasma P within the chamber 2. The plasma P generated by the plasma gun 14 is emitted in a beam shape from the plasma port to the internal space of the chamber 2. Thereby, plasma P is generated in the internal space of the chamber 2.

The anode 16 is a mechanism for guiding the plasma P from the plasma gun to a desired position. The anode 16 is a mechanism having an electromagnet or a magnet for inducing the plasma P. The anode 16 is provided on the wall 2d of the chamber and is disposed at a position facing the plasma gun 14 in the Y-axis direction. As a result, the plasma P is emitted from the plasma gun 14, diffused in the internal space of the chamber 2 while being directed to the positive side in the Y-axis direction, and then guided to the anode 16 while converging. The positional relationship between the plasma gun 14 and the anode 16 is not limited to the above, and any positional relationship may be adopted as long as negative ions can be generated.

The gas supply unit 6 is disposed outside the chamber 2. The gas supply portion 6 supplies gas into the chamber 2 through a gas supply port 26 formed in the wall portion 2 d. The gas supply port 26 is formed between the negative ion generating unit 4 and the object arranging unit 3. Here, the gas supply port 26 is formed at a position between the negative side end of the wall portion 2d in the X axis direction and the anode 16. However, the position of the gas supply port 26 is not particularly limited. The gas supply unit 6 supplies a gas serving as a raw material of negative ions. As the gas, for example, O can be used^-O of plasma negative ion raw material₂To NH^-NH of the source of the anion of the iso-nitride₂、NH₄Besides, it is C^-、Si^-C of plasma anion raw material₂H₆、SiH₄And the like. That is, it can be said that a material having a positive electron affinity is used. The gas also contains a rare gas such as Ar as a carrier gas for stabilizing discharge.

The circuit unit 7 includes: a variable power source 30, a 1 st wiring 31, a 2 nd wiring 32, resistors R1 to R3, and a switch SW 1. The variable power supply 30 applies a negative voltage to the cathode 21 of the plasma gun 14 and a positive voltage to the anode 16 across the chamber 2 at the ground potential. Thereby, the variable power supply 30 generates a potential difference between the cathode 21 and the anode 16 of the plasma gun 14. The 1 st wire 31 electrically connects the cathode 21 of the plasma gun 14 and the negative potential side of the variable power supply 30. The 2 nd wiring 32 electrically connects the anode 16 and the positive potential side of the variable power supply 30. The resistor R1 is connected in series between the 1 st intermediate electrode 22 and the variable power supply 30. The resistor R2 is connected in series between the 2 nd intermediate electrode 23 and the variable power supply 30. A resistor R3 is connected in series between chamber 2 and variable power supply 30. The switch SW1 switches the on/off state by receiving an instruction signal from the control unit 50. The switch SW1 is connected in parallel with the resistor R2. The switch SW1 is turned off when the plasma P is generated. On the other hand, the switch SW1 is turned on when the plasma P is stopped.

The voltage applying unit 8 applies a bias voltage to the substrate 11. The voltage applying section 8 includes: a power supply 36 for applying a bias voltage to the substrate 11; a 3 rd wiring 37 connecting the power source 36 and the object arranging unit 3; and a switch SW2 provided on the 3 rd wiring 37. The power supply 36 applies a positive voltage as a bias voltage. One end of the 3 rd wiring 37 is connected to the positive potential side of the power supply 36, and the other end is connected to the connection member 13. Thereby, the 3 rd wiring 37 electrically connects the power supply 36 and the substrate 11 via the connecting member 13 and the mounting member 12. The switch SW2 is switched in its on/off state by the control section 50. When negative ions are generated, the switch SW2 is turned on at a predetermined timing. When the switch SW2 is in the on state, the connection member 13 and the positive potential side of the power source 36 are electrically connected to each other, and a bias voltage is applied to the connection member 13. On the other hand, the switch SW2 is turned off at a predetermined timing when negative ions are generated. When the switch SW2 is in the off state, the link 13 and the power source 36 are electrically disconnected from each other, the bias voltage is not applied to the link 13, and the link 13 becomes in the floating state. When the connection member 13 is in a floating state, for example, the positive-negative balance of particles flowing into the substrate 11 at the time of plasma ON is minimized.

The Control Unit 50 is a device that controls the entire negative ion generating device 1, and includes an ECU [ Electronic Control Unit: an electronic control unit ]. The ECU is a CPU [ Central Processing Unit: central processing unit ], ROM [ Read Only Memory: read only Memory ], RAM [ Random Access Memory: random access memory), CAN [ Controller Area Network: controller area network ] communication circuits, and the like. In the ECU, for example, a program stored in the ROM is loaded into the RAM, and the program loaded into the RAM is executed by the CPU, thereby realizing various functions. The ECU may be constituted by a plurality of electronic units.

The control unit 50 is disposed outside the chamber 2. The control unit 50 further includes: a gas supply control unit 51 for controlling the supply of gas by the gas supply unit 6; a plasma control unit 52 for controlling the generation of the plasma P by the negative ion generation unit 4; and a voltage control unit 53 for controlling the application of the bias voltage by the voltage application unit 8. The control unit 50 controls the intermittent operation in which the generation and stop of the plasma P are repeated.

When the switch SW1 is turned off by the control of the plasma control unit 52, the plasma P from the plasma gun 14 is emitted into the chamber 2, and the plasma P is generated in the chamber 2. The plasma P contains neutral particles, positive ions, negative ions (when a negative gas such as oxygen is present), and electrons as constituent substances. When the switch SW1 is turned on by the control of the plasma control unit 52, the plasma P from the plasma gun 14 is not emitted into the chamber 2, and therefore the electron temperature of the plasma P in the chamber 2 is rapidly lowered. Therefore, electrons are easily attached to particles of the gas supplied into the chamber 2. This allows negative ions to be efficiently generated in the generation chamber 10 b. The voltage control unit 53 controls the voltage application unit 8 to apply the positive bias voltage to the substrate 11 when the plasma P stops. Thereby, the negative ions in the chamber 2 are guided to the substrate 11, and the substrate 11 is irradiated with the negative ions.

Fig. 2 is a graph showing the timing of turning on/off the plasma P and the state of the positive ions and negative ions flying toward the object. In the figure, the region indicated as "ON" indicates the state of generation of the plasma P, and the region indicated as "OFF" indicates the state of stoppage of the plasma P. At the time of time t1, plasma P stops. In the generation of the plasma P, many positive ions are generated. At this time, many electrons are also generated in the chamber 2. Also, when the plasma P stops, the positive ions sharply decrease. At this time, electrons also decrease. After the plasma P stops, the negative ions sharply increase from time t2 when a predetermined time elapses, and become a peak at time t 3. Further, the positive ions and the electrons gradually decrease from the time when the plasma P stops, and the positive ions and the negative ions are in the same amount and the electrons almost disappear in the vicinity of time t 3.

Here, the negative ion generating apparatus 1 further includes an ultraviolet light suppressing mechanism 60. The ultraviolet light suppressing mechanism 60 suppresses ultraviolet light UV with respect to the object arrangement portion 3, that is, ultraviolet light UV with respect to the substrate 11, between the negative ion generation portion 4 and the object arrangement portion 3. In the present embodiment, the ultraviolet light suppressing mechanism 60 includes aperture ratio adjusting members 61A and 61B (members) disposed between the negative ion generating unit 4 and the object disposing unit 3 in the chamber 2 and configured to suppress the passage of the ultraviolet light UV therethrough. The aperture ratio adjusting members 61A, 61B suppress the passage of ultraviolet light UV and allow the passage of supplies PM such as negative ions, radicals (atoms, molecules having unpaired electrons), and the like. In the present embodiment, the ultraviolet light UV from the plasma P and the supply substance PM travel mainly from the positive side toward the negative side in the X-axis direction, and are irradiated onto the substrate 11. Therefore, the X-axis direction is sometimes referred to as "irradiation direction". The positive side in the X-axis direction may be referred to as "upstream side in the irradiation direction", and the negative side in the X-axis direction may be referred to as "downstream side in the irradiation direction".

The aperture ratio adjusting members 61A and 61B are plate-shaped members having penetrating portions, respectively. The aperture ratio adjusting members 61A and 61B are disposed so as to be orthogonal to the irradiation direction, that is, so as to be developed parallel to the YZ plane. The aperture ratio adjusting members 61A and 61B are disposed so as to face each other in the irradiation direction. Here, the aperture ratio adjusting member 61A is disposed on the upstream side in the irradiation direction, and the aperture ratio adjusting member 61B is disposed on the downstream side in the irradiation direction. The aperture ratio adjusting members 61A and 61B are arranged so that the through portions thereof are shifted from each other when viewed from the irradiation direction, whereby the aperture ratio can be adjusted in advance.

An example of the aperture ratio adjusting members 61A and 61B will be described with reference to fig. 3. Fig. 3 (a) is a schematic view of the aperture ratio adjusting member 61A and the aperture ratio adjusting member 61B when they are overlapped with each other as viewed from the upstream side in the irradiation direction. Fig. 3 (B) is a schematic view of the aperture ratio adjusting member 61B from the upstream side in the irradiation direction, except for the aperture ratio adjusting member 61A. As shown in fig. 3 (a), the aperture ratio adjusting member 61A has circular through portions 62A distributed in a predetermined pattern. As shown in fig. 3 (B), the aperture ratio adjusting member 61B has circular through portions 62B distributed in a predetermined pattern. When viewed from the irradiation direction, penetrating portion 62A and penetrating portion 62B are arranged to be shifted from each other. Therefore, the penetrating portion 62A of the aperture ratio adjusting member 61A is closed by the plate portion (portion other than the penetrating portion 62B) of the aperture ratio adjusting member 61B.

As described above, the aperture ratio adjusting members 61A and 61B are configured such that no aperture portion exists when viewed from the irradiation direction. Therefore, when the ultraviolet light UV emitted from the plasma P travels in the irradiation direction, it is blocked by the combination of the aperture ratio adjusting members 61A, 61B. On the other hand, the aperture ratio adjusting members 61A and 61B are separated from each other with a slight gap in the irradiation direction. Therefore, the space SP1 (see fig. 1) on the plasma P side of the aperture ratio adjusting members 61A, 61B and the space SP2 (see fig. 1) on the substrate 11 side of the aperture ratio adjusting members 61A, 61B spatially communicate with each other through the through portion 62A, the gap, and the through portion 62B. Therefore, the supply material PM from the space SP1 can enter the space SP2 by repeating reflection between components and the like. Thereby, the supply PM, particularly, the negative ions are allowed to pass through the aperture ratio adjustment members 61A, 61B and irradiated onto the substrate 11. Since the ultraviolet light UV has a component inclined with respect to the irradiation direction and a component reflected between the members, a part of the ultraviolet light UV also enters the space SP 2. However, the amount of ultraviolet light UV entering is considerably smaller compared to the supply PM.

In fig. 3 (a) and (B), the combined structure of the aperture ratio adjusting members 61A and 61B has no opening when viewed from the irradiation direction. However, in order to increase the amount of the supply material PM passing through, an opening may be formed. Specifically, as shown in fig. 3B, opening OP (hatched region) may be formed by partially overlapping penetrating portion 62A (broken line) and penetrating portion 62B. The size of the opening OP can be controlled by adjusting the amount of displacement between the aperture ratio adjusting member 61A and the aperture ratio adjusting member 61B. In this way, the aperture ratio adjusting members 61A, 61B can adjust the aperture ratio by adjusting the amount of deviation therebetween.

Here, the aperture ratios of the aperture ratio adjusting members 61A and 61B will be described. The aperture ratio is a ratio of the total area of the openings OP formed in the reference region when the area of the reference region viewed from the irradiation direction is 100%. Here, the reference region may be a region of a portion overlapping with the substrate 11, which is denoted by "E1" in fig. 1. Alternatively, in a state where the substrate 11 is not mounted, a region of a portion overlapping with the mounting member 12 may be set as the reference region. In the example shown in fig. 3 (a), the aperture ratio is 0% because the combined structure of the aperture ratio adjusting members 61A, 61B does not have the opening OP. The aperture ratio is increased by increasing the opening OP by adjusting the amount of displacement of the aperture ratio adjusting members 61A, 61B or adjusting the size of the penetrating portions 62A, 62B. In the combined structure of the aperture ratio adjusting members 61A and 61B, the upper limit value of the aperture ratio is set when the penetrating portions 62A and 62B are completely overlapped. That is, even when the penetrating portions 62A and 62B are completely overlapped, the reference region E1 is blocked by the plate portion of the aperture ratio adjusting member 61A except for the penetrating portion 62A. Therefore, the upper limit of the aperture ratio is 100% or less. However, in some cases, the aperture ratio may be set to 100% by removing the aperture ratio adjusting members 61A and 61B themselves from the reference region E1. When the aperture ratio is set to 0%, the plasma P may be continuously generated without performing the intermittent control of the plasma P as shown in fig. 2 when the irradiation of electrons is permitted. When the aperture ratio is set to 0%, the supply material PM may be attracted by the electric field while the substrate 11 is not irradiated with the ultraviolet light UV.

The shape of the aperture ratio adjusting member is not particularly limited. For example, as shown in fig. 3 (c) and (d), the aperture ratio adjusting members 63A and 63B having comb-teeth-shaped penetrating portions 64A and 64B may be used. By adjusting the amount of deviation of the penetrating portions 64A, 64B of the aperture ratio adjusting members 63A, 63B, the aperture ratio may be set to 0% as shown in fig. 3 (c), or may be increased as shown in fig. 3 (d). Alternatively, a nested arrangement of plates may be used. In addition to the example shown in fig. 3, various shapes of the penetrating portion may be adopted. Further, the number of aperture ratio adjusting members may be further increased. By adopting various combinations, the configuration related to the combination of the aperture ratio adjusting member can also adjust the aperture ratio to 0% to 100%.

The number of the aperture ratio adjusting members may be 1. At this time, as shown in fig. 7 (a), the substrate 11 is closed by a plate 200 covering the upper portion thereof. In this structure, the supply material PM is irradiated while bypassing the outside of the plate 200. In the structure of fig. 7 (a), the aperture ratio based on the reference region E1 is 0%. However, when the size of the opening through which the supply material PM flows is large and the opening is aligned with the reference region E1, the size of the opening may be a size corresponding to 100% of the aperture ratio. In such a configuration, the ratio of the opening portion to the cross-sectional area of the chamber 2 is adjusted. When the irradiation of electrons is permitted, the plasma P may be continuously generated without performing intermittent control of the plasma P as shown in fig. 2.

For example, in the embodiment shown in fig. 3, the size of the through portion is smaller than the substrate 11. However, the penetration portions of the aperture ratio adjusting members 201, 202 may be formed large as shown in fig. 7 (b). For example, the size of the through portion may be "size of substrate 11/2". In this case, the uneven distribution can be suppressed by adjusting the overlapping manner of the aperture ratio adjusting members 201 and 202.

Next, the operation and effects of the negative ion generator 1 according to the present embodiment will be described.

The negative ion generating device 1 according to the present embodiment includes an ultraviolet light suppressing mechanism 60 for suppressing ultraviolet light UV with respect to the object arrangement portion 3 between the negative ion generating portion 4 and the object arrangement portion 3. When the negative ion generating unit 4 generates plasma P for generating negative ions, plasma light including ultraviolet light UV is directed toward the substrate 11 disposed in the object disposing unit 3. At this time, the ultraviolet light UV to the substrate 11 is suppressed by the ultraviolet light suppressing mechanism 60, and the ultraviolet light UV irradiated to the substrate 11 can be reduced or blocked. As described above, damage to the substrate 11 can be suppressed.

The ultraviolet light suppressing mechanism 60 includes aperture ratio adjusting members 61A and 61B disposed between the negative ion generating unit 4 and the object disposing unit 3 in the chamber 2 and configured to suppress the passage of the ultraviolet light UV therethrough. At this time, even if the shape of the entire chamber 2 is not changed (for example, as shown in fig. 6), the ultraviolet light UV with respect to the substrate 11 can be suppressed only by adding the aperture ratio adjusting members 61A and 61B to the conventional chamber 2.

The aperture ratio adjusting members 61A, 61B suppress the passage of ultraviolet light UV and allow the passage of negative ions. In this case, the ultraviolet light UV to the substrate 11 can be suppressed without providing a complicated mechanism for moving the members as shown in fig. 4.

The present invention is not limited to the above embodiments.

For example, the negative ion generating device 1 shown in fig. 4 may be employed. In the example shown in fig. 4, the ultraviolet light suppressing mechanism 60 may have a switching unit 67, and the switching unit 67 may switch the position of the opening/closing member 66 (member) between the time when the plasma P is generated by the negative ion generating unit 4 and the time when the plasma P is stopped. The opening/closing member 66 is a member facing the substrate 11 and the mounting member 12 on the downstream side in the irradiation direction. The opening/closing member 66 is a flat plate member having no through-hole as shown in fig. 3. The switching unit 67 can be rotated or reciprocated by applying a driving force to the opening/closing member 66. Thus, the switching unit 67 can switch between a state in which the substrate 11 is covered with the opening/closing member 66 and a state in which the substrate 11 is exposed by retracting the opening/closing member 66.

At this time, at the time point when the plasma P is being generated (at the time point of "ON" in fig. 2), the switching unit 67 can block the ultraviolet light UV with respect to the substrate 11 by disposing the opening/closing member 66 between the negative ion generating unit 4 and the substrate 11. On the other hand, at the time when the plasma P stops (at the time of OFF in fig. 2), the switching unit 67 can irradiate the substrate 11 with the negative ions generated by the negative ion generating unit 4 by removing the opening/closing member 66. According to the configuration shown in fig. 4, when the plasma P is being generated, the opening/closing member 66 having no opening can block the ultraviolet light UV more reliably than the configuration using the aperture ratio adjusting member shown in fig. 1. Further, by exposing the substrate 11 when the plasma P is stopped, more negative ions can be irradiated onto the substrate 11 than in the configuration using the aperture ratio adjusting member shown in fig. 1.

The negative ion generator 1 shown in fig. 5 may be employed. In the example shown in fig. 5, the magnetic field forming portion 80 is provided in the space SP2 on the substrate 11 side of the aperture ratio adjusting members 61A and 61B. The magnetic field forming unit 80 includes magnetic field generating devices 81 provided on the positive side and the negative side in the Y-axis direction, respectively, so as to sandwich the chamber 2. The magnetic field forming portion 80 forms a magnetic field in a direction along the mounting surface 12a of the mounting member 12. That is, the magnetic field forming unit 80 forms a magnetic field in a direction along the irradiated surface 11a of the substrate 11. The direction along the placement surface 12a and the irradiated surface 11a is a direction substantially parallel to these surfaces. In the example shown in fig. 5, the magnetic flux B generated by the magnetic field generating device 81 extends substantially parallel to the Y-axis direction. The magnetic field forming portion 80 can trap electrons by forming a magnetic field near the substrate 11. This allows the magnetic field forming portion 80 to reduce the amount of electrons irradiated onto the substrate 11. Therefore, by adopting the configuration shown in fig. 5, it is possible to continuously generate the plasma P without performing the intermittent control of the plasma P as shown in fig. 2.

Further, the configuration related to the combination of the magnetic field forming unit 80, the object arrangement unit 3, and the voltage application unit 8 can function as the discharge unit 90 that performs magnetron discharge. The negative ion generator 4 can also function as a radical supply source for generating radicals. The discharge portion 90 is a mechanism capable of performing magnetron discharge using radicals supplied from a radical supply source. Accordingly, the discharge portion 90 can also generate negative ions irradiated onto the substrate 11 by magnetron discharge.

Specifically, the magnetic field forming unit 80 can apply a magnetic field substantially parallel to the surface 11a of the substrate 11 to be irradiated. That is, a magnetic field substantially parallel to the irradiated surface 11a is formed at the position of the irradiated surface 11a (and the placement surface 12 a). The voltage application unit 8 can apply a bias voltage perpendicular to the surface 11a of the substrate 11 to be irradiated. In this way, the discharge portion 90 can perform magnetron discharge of "E × B" at a position near the irradiation target surface 11 a. The negative ion generator 4 can supply a large amount of radicals from the high-density plasma P. This facilitates discharge unlike a gas in an underlying state, and enables modification by plasma irradiation. Further, although plasma light is newly generated by magnetron discharge, the plasma light is easily discharged as compared with the plasma P of the negative ion generating part 4, and thus the ultraviolet light is small. Therefore, damage to the substrate 11 can be suppressed within an allowable range. By such magnetron discharge, the substrate 11 serving as the anode is irradiated with newly generated negative ions and electrons.

In addition, the negative ions and the electrons exhibit a behavior of revolving around the magnetic flux B. At this time, the electrons revolve around the magnetic flux B with a smaller diameter, and the negative ions revolve around the magnetic flux B with a larger diameter. Therefore, by adjusting the magnetic field of the magnetic field forming portion 80 in advance, it is possible to make the negative ions that are turned largely contact with the substrate 11 as much as possible, and the electrons that are turned comparatively small do not contact with the substrate 11 as much as possible. This makes it easier for the substrate 11 to be irradiated with negative ions than with electrons.

In the above-described embodiment and modification, the ultraviolet light suppressing mechanism is configured by providing a new member in the chamber 2. Alternatively, the ultraviolet light suppressing mechanism may be constituted by a chamber 102 that blocks the ultraviolet light UV with a wall portion between the negative ion generating unit 4 and the object arranging unit 3. In this case, the ultraviolet light UV to the substrate 11 can be suppressed without adding a separate member as shown in fig. 1 and 4. Specifically, as shown in fig. 6, the object arrangement portion 3 and the substrate 11 may be arranged at positions to which the ultraviolet light UV from the plasma P does not directly face.

The chamber 102 shown in fig. 6 includes a plasma chamber RM1 for generating plasma P and an irradiation chamber RM2 for irradiating negative ions to the substrate 11. The plasma chamber RM1 is a space corresponding to the internal space of the chamber 2 in fig. 1, and is formed by a space surrounded by the wall portions 2a to 2 d. Irradiation chamber RM2 is formed by a space extending to the negative side in the Y axis direction at the end of the negative side in the X axis direction of plasma chamber RM 1. Specifically, the irradiation chamber RM2 includes: a wall portion 2e extending the wall portion 2a to the negative side in the Y-axis direction; a wall portion 2f extending from the wall portion 2c to the negative side in the Y-axis direction; and a wall portion 2g connecting the negative side end portions of the wall portions 2e and 2f in the Y axis direction. In the plasma chamber RM1, the constituent elements of the negative ion generating unit 4 are provided at the same positions as those in fig. 1. In contrast, the object placement unit 3 is provided in the wall portion 2e of the irradiation chamber RM 2.

A direction (X-axis direction) orthogonal to the irradiated surface 11a of the substrate 11 is defined as an irradiation direction. At this time, the irradiation chamber RM2 of the installation object placement unit 3 is disposed at a position deviated from the plasma chamber RM1 in the direction (here, the Y-axis direction) orthogonal to the irradiation direction. The irradiation chamber RM2 is disposed downstream of the plasma gun 14 and the anode 16 in the irradiation direction, and is disposed downstream of the edge Pa of the plasma P in the irradiation direction. The edge Pa of the plasma P indicates a boundary portion of a light emission range that can be visually recognized when the plasma P is generated at the maximum output. In addition, the profile of the plasma P has a certain width because of the difference in the emission intensity.

Due to such a positional relationship, the plasma P cannot be directly observed when viewed from the substrate 11. Specifically, when the negative ion generating unit 4 side is viewed from the reference position on the substrate 11 side, all or a part of the plasma P is not observed. For example, when the end of the substrate 11 is set to the reference position P1, the edge Pa of the plasma P may not be visible from the reference position P1, the center CP2 of the anode 16 may not be visible from the reference position P1, the center CP1 of the plasma P (the center of the region between the plasma torch 14 and the anode 16) may not be visible from the reference position P1, or the center CP3 of the plasma torch 14 may not be visible from the reference position P1. The state in which the center position CP1 is not visible from the reference position P1 is a state in which a broken line VL connecting the reference position P1 and the center position CP1 interferes with the wall portion of the chamber 102 (see fig. 6). The center of the mounting member 12 may be set to the reference position P2 on the substrate 11 side. By establishing these positional relationships, the ultraviolet light UV directed from the plasma P toward the substrate 11 is blocked by the wall portion 2c of the chamber 102. As described above, the chamber 102 constitutes the ultraviolet light suppressing mechanism 60.

The negative ion generator 1 shown in fig. 6 also includes a magnetic field forming unit 80 that forms a magnetic field in a direction along the surface 11a to be irradiated and the mounting surface 12a of the substrate 11. Thereby, negative ions are irradiated onto the substrate 11 by magnetron discharge. The magnetic field forming portion 80 may be omitted.

For example, although the plasma gun 14 is a pressure gradient plasma gun in the above embodiment, the plasma gun 14 is not limited to a pressure gradient plasma gun as long as it can generate plasma in the chamber 2.

In the above embodiment, only one set of the plasma torch 14 and the anode 16 for guiding the plasma P is provided in the chamber 2, but a plurality of sets may be provided. Further, the plasma P may be supplied from a plurality of plasma guns 14 to one site.