JP2001239153A - Ion generator and film making apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film making apparatus which can make a uniform film at a high speed. SOLUTION: Since a pressure gradient type plasma gun for generating plasma by a direct current arc discharge is used as a plasma gun 10, the plasma of a high ionization percentage can be generated. Since a cusp magnetic field is formed by a pair of coils 18, 24, a high density Ar ion beam IB can be obtained. Since a treatment chamber 30 can be held in a high vacuum state, no carrier gas is supplied to the periphery of a substrate WA so that the periphery of the substrate WA can be kept clean. In this way, a wiring film of a desired thickness with reduced impurities can be formed promptly and uniformly on the substrate WA.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention has an object to provide an ion generator capable of supplying high-density and uniform ions over a large area by a simple mechanism, and a film forming apparatus using the same. .

[0002]

2. Description of the Related Art As an ion source incorporated in an accelerator or the like, for example, a duoplasmatron is known. In this duoplasmatron, plasma discharge is generated by emitting thermoelectrons from the cathode while introducing a source gas between the cathode and the anode. The generated plasma is confined in a cylindrical magnetic field and supplied to the opening of the anode.
After the ions in the plasma pass through the anode opening,
It is extracted by suitably provided electrodes, accelerated, and emitted from this ion source.

A microwave excitation type ion source is known as an ion source for film formation. In such a microwave-excited ion source, by irradiating a microwave through a quartz window while introducing a source gas into a plasma chamber in which an appropriate magnetic field is formed,
Generates plasma efficiently. The ions in the plasma are extracted and accelerated by appropriately provided honeycomb-shaped electrodes, and are emitted from the ion source.

[0004]

However, a duoplasmatron is a low emittance ion source for an accelerator or the like, and cannot supply ions uniformly over a large area.

[0005] Further, in a microwave-excited ion source, there is a limit to the ionization rate due to microwaves, and the apparatus becomes large-sized to supply high-density and uniform ions over a large area.

Accordingly, an object of the present invention is to provide an ion generator capable of supplying high-density and uniform ions over a large area by a simple mechanism.

A further object of the present invention is to provide a film forming apparatus which enables uniform film formation at high speed by utilizing the above-described ion generator.

[0008]

In order to solve the above-mentioned problems, a first ion generating apparatus of the present invention comprises a plasma gun for generating plasma by arc discharge, and a plasma gun for generating plasma by arc discharge. A magnetic field forming means for forming a cusp magnetic field in a region, a separation electrode (ie, an anode) arranged opposite to the emission port to attract and separate electrons from plasma in a predetermined region, and to emit plasma more than the separation electrode And an extraction electrode that is disposed on the direction side and extracts positive ions from plasma in a predetermined region.

In the above apparatus, a plasma gun for generating plasma by arc discharge is used, so that a large amount of plasma can be continuously and stably generated by a simple mechanism, and ions can be efficiently generated in a large area along a magnetic field. Can be spread out and distributed. Further, since the magnetic field forming means forms the cusp magnetic field in a predetermined region facing the exit of the plasma from the plasma gun, the generated plasma can be efficiently confined in the predetermined region. At this time, electrons can be efficiently removed from the cusp magnetic field in the predetermined area by the separation electrode, and positive ions can be efficiently extracted from the cusp magnetic field in the predetermined area by the extraction electrode, so that a large amount of positive ions can be extracted. it can. Note that, as the plasma gun, a pressure gradient gun using a DC arc discharge can be preferably used.

Further, according to a preferred embodiment of the above device,
The magnetic field forming means is composed of a pair of circular coils arranged opposite to each other in the plasma emission direction with a predetermined region interposed therebetween, and the cusp magnetic field is a spindle shape rotationally symmetric about the central axis of the pair of circular coils. .

[0011] In the above apparatus, since a spindle-shaped cusp magnetic field facing the plasma emission port is formed by the pair of circular coils, the plasma can be confined simply and efficiently, and positive ions can be efficiently extracted.

[0012] The second ion generator of the present invention comprises:
A plasma gun that generates plasma by arc discharge, a separation electrode that is disposed to face an emission port of the plasma gun, and that attracts and separates electrons from plasma in a predetermined region facing the emission port, An extraction electrode that is arranged on the plasma emission direction side and extracts positive ions from the plasma in a predetermined area and a sector including a shielding part and a passing part are moved to extract positive ions in the predetermined area to the extraction electrode. And a chopper for adjusting the timing to be performed.

In the above apparatus, a plasma gun for generating plasma by arc discharge is used, so that a large amount of plasma and a large amount of positive ions can be continuously and stably generated by a simple mechanism. Further, in the above device, the chopper adjusts the timing at which the positive ions in the predetermined region are extracted to the extraction electrode, so that the positive ions can be emitted at a desired timing. For example, by operating a chopper sector at a constant cycle, positive ions emitted as periodic pulses can be obtained, and by applying an AC extraction electric field so as to synchronize with the pulsed ions extracted to the acceleration electrode. Thus, a pulsed ion current can be efficiently obtained.
Note that, as the plasma gun, a pressure gradient gun using a DC arc discharge can be preferably used.

Further, the film forming apparatus of the present invention supports the first and second ion generators and a target formed of a film forming material at a position where positive ions emitted from the ion generator are incident. A target support member and a substrate support member for supporting a substrate on which a film is to be formed at a position opposed to the target without blocking positive ions incident on the target.

In the above apparatus, since the first and second ion generators are used, a large amount of positive ions can be continuously and stably generated, and the target can be sputtered stably and quickly. Can be. Therefore, a film can be quickly and uniformly formed on a substrate by a simple mechanism.

By utilizing the above-described ion generator for film formation, it is possible to prevent the substrate from being damaged by plasma, and to increase the degree of vacuum around the substrate to reduce the influence of residual gas. Can be. Further, local erosion of the target and generation of an arc around the target can be easily prevented, and the target material to be sputtered does not matter. Further, since the beam energy and the irradiation area of the positive ions can be strictly controlled, the controllability of film formation can be improved.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a film forming apparatus incorporating an ion generator according to a first embodiment of the present invention will be described.

FIG. 1 is a diagram schematically illustrating the overall structure of a film forming apparatus. The film forming apparatus includes a plasma gun 10 that generates plasma having a high ionization rate, and an ion beam forming unit 20 that separates positive ions from the plasma emitted from the plasma gun 10 and emits the ions as a beam having a desired energy and density distribution. And the ion beam forming unit 2
A processing chamber 30 for performing sputtering film formation using an ion beam from 0 is provided. Here, the plasma gun 10
And the ion beam forming unit 20 constitute an ion generator.

The plasma gun 10 has a plasma beam PB
This is a pressure gradient type plasma gun that generates a pressure gradient, and its main body is mounted on a cylindrical portion 21 provided on a side wall of the ion beam forming unit 20. This body part is a cathode 11
The glass tube 12 is closed at one end. In a glass tube 12, a cylinder 13 made of molybdenum Mo is provided.
Are fixed to the cathode 11 and arranged concentrically. Inside the cylinder 13, a disk 14 made of LaB ₆ and a pipe 15 made of tantalum Ta are incorporated.
First and second intermediate electrodes 16, 17 are concentrically arranged in series between an end of the glass tube 12 opposite to the cathode 11 and an end of the tubular portion 21. ing. In the first intermediate electrode 16, an annular permanent magnet 16a for converging the plasma beam PB is incorporated. An annular electromagnet coil 17a for converging the plasma beam PB is also built in the second intermediate electrode 17. In addition,
An annular steering coil 18 is provided around the cylindrical portion 21 to guide the plasma beam PB generated on the cathode 11 side and extracted to the first and second intermediate electrodes 16 and 17 to the ion beam forming unit 20. I have.

The operation of the plasma gun 10 is controlled by a gun driving device 41. This gun driving device 41
Can turn on / off the power supply to the cathode 11 and adjust the voltage supplied thereto, and further adjust the power supply to the first and second intermediate electrodes 16, 17 and the electromagnet coil 17a. The state of the plasma beam PB supplied into the ion beam forming unit 20 is controlled by such a gun driving device 41. In this plasma gun 10, a DC arc discharge having a high ionization rate is used, and 10 to several tens% of the carrier gas can be ionized.

A pipe 15 disposed on the innermost side of the plasma gun 10 is provided with an Ar which is a source of the plasma beam PB.
The carrier gas is introduced into the plasma gun 10, and is connected to a gas supply source 43 via a flow control unit 42. The supply amount of the carrier gas to the plasma gun 10 can be, for example, 80 SCCM or more.

The ion beam forming unit 20 includes a partition 22a,
And divided into three chambers 23a and 23
b and 23c. Each chamber 23a, 23
b and 23c are vacuum vessels, each of which is exhausted.
Pump 50 is installed to enable differential pumping
You. That is, the first chamber 23a is, for example, 10^-1~
10 ^-2Pa and the second chamber 23b
Will respond 10^-3-10^-FourAbout Pa
And the third chamber 23c has an additional 10^-Four-10^-FiveP
a. That is, the third chamber 23
c is maintained in a high vacuum state.

In the first chamber 23a, the ion beam IB is separated from the plasma beam PB. Therefore, the first
The chamber 23a has an anode 25 that is an anode having a circular opening 25a formed coaxially with the plasma gun 10;
It has a cylindrical extraction electrode 26 arranged coaxially with the plasma gun 10 so that the circular opening 25a is desired. Further, an annular coil 24 is disposed around and coaxial with the plasma gun 10 around the first chamber 23a. That is, the anode 25 is interposed between the annular coil 24 and the steering coil 18 so as to be coaxial therewith.

Annular coil 24 and steering coil 18
Are a pair of circular electromagnet coils capable of forming mutually opposite magnetic fields.
A spindle-shaped cusp magnetic field is formed as a magnetic field forming means in a predetermined area near the circular opening 25a of the anode 25 on the front of the anode 25. The plasma beam PB emitted from the plasma gun 10 is confined in the cusp magnetic field formed by the coils 18 and 24. The electrons in the plasma beam PB confined in the cusp magnetic field proceed along the lines of magnetic force of the cusp magnetic field and are attracted to the anode 25. On the other hand, positive ions in the plasma beam PB, that is, A
The r ⁺ ions are attracted to the extraction electrode 26 and
6 through the mesh electrode portion 26a. Thereby, an ion beam IB is formed behind the mesh electrode portion 26a.

The anode 25 on which a large amount of electrons enter as a separation electrode is overheated by a large current. Therefore, the anode 2
Reference numeral 5 uses a high melting point metal such as tungsten and is protected by water cooling.

The mesh electrode portion 26 a provided on the extraction electrode 26 on which Ar ions enter is made of a high melting point metal and is insulated from the anode 25. In addition, this mesh electrode part 26
a may be a honeycomb-shaped or porous electrode.

FIG. 2 is a sectional view conceptually illustrating the magnetic field around the annular coils 24a and 24b. Annular coil 24
An annular magnetic field is formed in each of the parts a and 24b so as to surround it. As a result, both annular coils 24a, 24
It can be seen that a spindle-shaped cusp magnetic field is formed during b. In such a cusp magnetic field, the plasma is confined, but the electrons in the plasma beam PB are
Since the mass is small and negatively charged, it proceeds along the line of magnetic force and is attracted to the anode 25 to become a current of the anode 25. Some electrons incident on the cusp magnetic field go straight, but are reflected by the extraction electrode 26 which is grounded or to which a negative bias is applied, and eventually captured by the anode 25. on the other hand,
Since Ar ions in the plasma beam PB have a large mass and a positive charge, they are attracted to the extraction electrode 26 and pass through the mesh electrode portion 26a to become an ion beam IB.

Returning to FIG. 1, in the second chamber 23b,
The ion beam IB is accelerated. For this reason, the second chamber 23b has an accelerating electrode 27 opposed to the extraction electrode 26 and arranged coaxially therewith. The ion beam IB guided to the second chamber 23b after passing through the extraction electrode 26 is accelerated until the energy required for sputtering is reached, and passes through the mesh electrode portion 27a of the acceleration electrode 27. The accelerating electrodes 27 need not be provided in one stage as shown in the figure, but may be provided in multiple stages as necessary.

In the third chamber 23c, the ion beam I
Only necessary ions are separated from B. For this purpose, the third chamber 23c is provided with a magnetic field applying device 28 composed of a deflecting electromagnet and a beam shaping device 29 for shaping the separated ion beam IB into an appropriate beam shape. Acceleration electrode 2
The ion beam IB emitted from the exit port 7 enters the entrance port 28a of the magnetic field applying device 28, is deflected by the magnetic field B perpendicular to the paper surface, changes its traveling direction by 90 °, and exits from the exit port 28b. Note that the magnetic field applying device 28
The magnetic field intensity to be formed on the path of the ion beam IB can be arbitrary, and only necessary plus ions, that is, only Ar ions can be extracted in this embodiment, and neutral particles and the like are removed. . When passing through the beam shaping device 29, the ion beam IB made of Ar ions emitted from the outlet port 28b is adjusted to an appropriate beam size and shape by a magnetic field or an electric field, and is adjusted to the third chamber 23c.
That is, the light is emitted from the ion beam forming unit 20.

Anode 25, extraction electrode 26, and acceleration electrode 2
The application of the voltage to 7 is controlled by the electrode power supply device 51. The electrode power supply device 51 can turn on / off the power supply to the anode 25, the extraction electrode 26, and the acceleration electrode 27 at an appropriate timing, and can adjust the supply voltage thereto to a desired value. Supply of electric power to the pair of coils 18 and 24 is controlled by a coil power supply device 52. This coil power supply device 52 adjusts the power supply to both coils 18 and 24 appropriately, so that the circular opening 2
A cusp magnetic field having a desired intensity can be formed near 5a. Power supply to the beam shaping device 29 is controlled by a shaping power supply device 53.

The processing chamber 30 is a vacuum vessel to which an exhaust pump 54 is attached, and can maintain a high vacuum, that is, 10 ^-5 Pa or less as in the third chamber 23c. An opening A for passing the ion beam IB is provided between the processing chamber 30 and the third chamber 23c.
P is provided. The processing chamber 30 includes a target holder 31 serving as a target support member for supporting a target TA made of a metal wiring material such as Cu so that a film forming material surface thereof faces the opening AP, and a substrate WA having a film forming surface. A substrate holder 32 that is a substrate support member that supports the target TA so as to face the target TA. Target holder 3
1 has a conductive support plate 31a, so that the potential of the target TA can be adjusted appropriately.
The substrate holder 32 has a conductive support plate 32a, so that the potential of the substrate WA can be appropriately adjusted.

The application of voltage to the support plates 31a and 32a is controlled by a power supply unit 55. This power supply device 55 can turn on / off the power supply to both support plates 31a and 32a at an appropriate timing, and can adjust the supply voltage to these to a desired value.

The substrate holder 32 adjusts the posture of the substrate WA facing the target TA together with the support plate 32a, or moves the substrate WA around the center axis of the support plate 32a.
It can be rotated together with 2a. The target TA and the substrate WA can be put in and out of the processing chamber 30 via a load lock chamber (not shown).

Hereinafter, the operation of the film forming apparatus according to the first embodiment shown in FIG. 1 will be described. In this film forming apparatus, a plasma beam PB is generated by the discharge from the cathode 11 of the plasma gun 10. This plasma beam P
B reaches the first chamber 23a by being guided by a magnetic field determined by the electromagnet coil 17a and the like. In the first chamber 23a, the steering coil 18 and the annular coil 2
4 to the cusp magnetic field formed by the plasma beam PB
Is incident and confined here. Among the confined plasma, the electrons are guided to the lines of magnetic force and are attracted to the anode 25. On the other hand, Ar ions that have traveled straight through the cusp magnetic field are attracted to the extraction electrode 26 and travel straight, and the high-density ion beam I
B is formed. This ion beam IB is accelerated by the acceleration electrode 27 in the second chamber 23b to have a desired energy, and reaches the third chamber 23c. In the third chamber 23c, only necessary ions are separated from the ion beam IB by the magnetic field applying device 28, the beam shape of the ion beam IB is shaped by the beam shaping device 29, and the beam is incident on the processing chamber 30. The ion beam IB incident on the processing chamber 30 is incident on the target TA to sputter the wiring material. The fine particles of the wiring material emitted from the target TA by sputtering are incident on the surface to be processed of the opposing substrate WA and are gradually deposited. By continuing such sputtering film formation for a predetermined time, a wiring film having a desired thickness can be formed on the substrate WA. At this time, since a pressure gradient plasma gun that generates plasma by DC arc discharge is used as the plasma gun 10,
Plasma with a high ionization rate can be generated.
Further, since a cusp magnetic field is formed by the steering 17 and the annular coil 24, a high-density Ar ion beam IB can be obtained. Further, since the processing chamber 30 can be maintained at a high vacuum, a carrier gas is not introduced around the substrate WA, so that the periphery of the substrate WA can be kept clean. Therefore, a wiring film having a desired thickness and a small amount of impurities can be quickly and uniformly formed on the substrate WA.

(Second Embodiment) Hereinafter, a film forming apparatus incorporating an ion generator according to a second embodiment of the present invention will be described. The film forming apparatus according to the second embodiment is a modification of the film forming apparatus according to the first embodiment, and the same parts are denoted by the same reference numerals and the description thereof will not be repeated.

FIG. 3 is a diagram schematically illustrating the entire structure of the film forming apparatus. In this film forming apparatus, a pair of coils 1
A cusp magnetic field is formed by 8 and 24, and the output timing of the ion beam IB is adjusted using the chopper 124. For this reason, an extraction electrode 126 having a built-in chopper 124 is provided in the first chamber 23a. The chopper 124 includes a disk-shaped sector 124 a and a sector 1.
Drive 124 for rotating 24a about its central axis
b, and a rotation control device 152 for controlling the operation of the driving device 124b. The sector 124a includes an extraction electrode 126.
And the ion beam IB accelerated by the mesh electrodes 126a and 126b passing through the circular opening 25a of the anode 25 is cut off at an appropriate timing. be able to.

FIG. 4 is a diagram for explaining the structure of the sector 124a. The sector 124a includes a shielding portion 124d that blocks Ar ions between the mesh electrodes 126a and 126b,
And a passage portion 124e through which the mesh electrodes 126a and 126b transmit Ar ions. The potential of the sector 124a may be a float, or both the mesh electrodes 126
a, 126b.

Returning to FIG. 3, in the third chamber 23c,
An ion sensor 170 composed of a Faraday cup or the like is provided between the acceleration electrode 27 and the magnetic field application device 28. The ion sensor 170 is driven by a sensor driving device 171, and outputs the ion beam I passing through the acceleration electrode 27.
The ion current of B can be detected.

Hereinafter, the operation of the film forming apparatus according to the second embodiment shown in FIG. 3 will be described. The plasma beam PB from the plasma gun 10 is supplied to the first chamber 23a. The plasma introduced into the first chamber 23a is confined in a cusp magnetic field formed by the annular coil 24 and the steering coil 18, and electrons in the plasma are
The Ar ions are attracted by the anode 25, and the Ar ions are attracted by the extraction electrode 26, thereby forming an ion beam IB. The ion beam IB can be formed into a pulse having a desired period by operating the chopper 124 at an appropriate timing. Such a pulsed ion beam IB
Is accelerated by the accelerating electrode 27 to which a voltage that increases or decreases in the pulse cycle of the ion beam IB or an integral multiple thereof in the second chamber 23b is turned to a desired energy, and reaches the third chamber 23c. Third chamber 23
In (c), only necessary ions are separated from the ion beam IB by the magnetic field applying device 28, the beam shape of the ion beam IB is shaped by the beam shaping device 29, and is incident on the processing chamber 30. The ion beam IB incident on the processing chamber 30 is periodically incident on the target TA to sputter the wiring material. The sputtered particles emitted in pulses from the target TA are incident on the surface to be processed of the opposing substrate WA and are gradually deposited. By continuing such sputtering film formation for a predetermined time, a wiring film having a desired thickness can be formed on the substrate WA. At this time, since the supply of the ion beam IB to the target TA is pulsed using the chopper 124, the controllability of film formation can be improved. Furthermore, by applying an alternating current to the accelerating electrode 27 synchronously with the cycle of the chopper 124 or an integral multiple of the cycle, the ion beam IB can be bunched and its energy can be made uniform.

Although the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment.
For example, in the above embodiment, the target TA is sputtered to form a film on the substrate WA.
By arranging the substrate WA at the position A, an ion beam etching apparatus that performs high-speed and uniform dry etching can be obtained. At this time, the target TA and the substrate WA
If a mechanism for exchanging the positions is provided, the processing apparatus can continuously or repeatedly perform etching and film formation.

In the second embodiment, the cusp magnetic field is formed by the pair of coils 18 and 24 to increase the extraction efficiency of the ion beam IB. However, the formation of the cusp magnetic field is not essential. That is, even if the annular coil 24 provided around the second chamber 23b is removed, the output timing of the ion beam IB can be adjusted using the chopper 124 to achieve ion bunching and uniformity.

In the above embodiment, the target TA
Is formed as a conductive wiring material, but an insulating material can also be formed. In this case, in order to prevent charge-up of the target, the target itself is made cylindrical, and the target is rotated around the cylindrical axis while the ion beam IB is incident on the side surface. If a conductive roll that rotates with the target in contact with the side surface portion is provided behind the target, that is, on the side surface portion where the ion beam IB does not enter, the charge up of the target can be prevented.

[0043]

As is apparent from the above description, according to the first ion generator of the present invention, since a plasma gun that generates plasma by arc discharge is used, a large amount of plasma can be continuously produced by a simple mechanism. And ions can be efficiently spread and distributed over a large area along the magnetic field. Further, since the magnetic field forming means forms the cusp magnetic field in a predetermined region facing the exit of the plasma from the plasma gun, the generated plasma can be efficiently confined in the predetermined region. At this time, electrons can be efficiently removed from the cusp magnetic field in the predetermined area by the separation electrode, and positive ions can be efficiently extracted from the cusp magnetic field in the predetermined area by the extraction electrode, so that a large amount of positive ions can be extracted. it can.

According to the first ion generator of the present invention, since a plasma gun for generating plasma by arc discharge is used, a large amount of plasma and a large amount of positive ions can be continuously stabilized by a simple mechanism. Can be generated. Further, in the above device, the chopper adjusts the timing at which the positive ions in the predetermined region are extracted to the extraction electrode, so that the positive ions can be emitted at a desired timing.

Further, according to the film forming apparatus of the present invention, since the first and second ion generators are used, a large amount of positive ions can be continuously and stably generated, and the target can be stably formed. Even spatter can be sputtered quickly. Therefore, a film can be quickly and uniformly formed on a substrate by a simple mechanism.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a structure of a film forming apparatus according to a first embodiment.

FIG. 2 is a diagram illustrating a main part of the apparatus of FIG. 1;

FIG. 3 is a diagram illustrating a structure of a film forming apparatus according to a second embodiment.

FIG. 4 is a diagram for explaining a main part of the apparatus shown in FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Plasma gun 18 Steering coil 20 Ion beam formation part 24 Annular coil 25 Anode 25a Circular opening 26 Extraction electrode 27 Acceleration electrode 28 Magnetic field application device 29 Beam shaping device 30 Processing chamber 31 Target holder 32 Substrate holder 41 Gun drive device 43 Gas supply source Reference Signs List 50 exhaust pump 51 electrode power supply device 52 coil power supply device 54 exhaust pump 124 chopper 124b drive device 152 rotation control device WA board

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/203 H01L 21/203 S

Claims (4)

[Claims] 1. A plasma gun for generating plasma by arc discharge, magnetic field forming means for forming a cusp magnetic field in a predetermined area facing a plasma emission port from the plasma gun, and a magnetic field generating means arranged to face the emission port. A separation electrode that attracts and separates electrons from the plasma in the predetermined region, and is disposed on the plasma emission direction side of the separation electrode,
An extraction electrode for extracting positive ions from plasma in the predetermined region. 2. The magnetic field forming means includes a pair of circular coils disposed opposite to each other in the plasma emission direction with the predetermined region interposed therebetween, and the cusp magnetic field is formed by a central axis of the pair of circular coils. 2. The ion generator according to claim 1, wherein the ion generator has a spindle shape that is rotationally symmetric about the axis. 3. A plasma gun for generating plasma by arc discharge, and a separator arranged to face an emission port of the plasma gun and attracting and separating electrons from plasma in a predetermined area facing the emission port. An electrode, disposed on the plasma emission direction side of the separation electrode,
An extraction electrode for extracting positive ions from the plasma in the predetermined region, and a sector including a shielding portion and a passing portion are moved to adjust a timing at which the positive ions in the predetermined region are extracted to the extraction electrode. And an ion generator comprising: 4. An ion generator according to claim 1, further comprising: a target support member configured to support a target formed of a film forming material at a position where positive ions emitted from the ion generator are incident. A film forming apparatus comprising: a substrate supporting member that supports a target substrate at a position facing the target without blocking positive ions incident on the target.