JP2020173984A - Ion source, ion implanter, and magnesium ion generation method - Google Patents

Abstract

To provide an ion source having a long life, which can generate a stable magnesium ion with a simple structure.SOLUTION: An ion source 10 according to the present invention heats a cathode electrode 22 by an energized filament 20 and emits thermoelectrons from an electron emitting surface 38 toward a repeller electrode 23, controls the potentials of the cathode electrode 22 and the repeller electrode 23 such that the thermoelectrons reciprocate between the cathode electrode 22 and the repeller electrode 23, and decomposes introduced sputter gas by the thermoelectrons to generate plasma of sputter gas. A raw material block 28 is sputtered by the ions in the plasma to generate positively charged magnesium ions.SELECTED DRAWING: Figure 2

Description

The present invention relates to an ion source, and more particularly to an ion source technique used in an ion implantation apparatus that ionizes magnesium (Mg) and implants it into a substrate.

In recent years, for example, a technique for implanting magnesium (Mg) ions as a dopant on a substrate made of gallium nitride (GaN) has been put into practical use, and an ion implantation device having an ion source for generating an ion beam of magnesium has been developed. There is.

In order to generate magnesium ions in such an ion source, solid magnesium placed in a container is heated in a vacuum to sublimate and vaporize, and the magnesium gas is arc-discharged in the ion generation container. There is a method of generating plasma and ionizing it.

In this case, for the purpose of simplifying the device configuration, a raw material gas introduction pipe that introduces a magnesium gas into a pipe that supplies a discharge auxiliary gas such as argon in order to assist the discharge of magnesium in the ion generation container. It is widely practiced to introduce these two types of gases into the ion generation container via only one raw material gas introduction pipe.

However, in such a conventional technique, when sublimating solid magnesium, for example, as shown in FIG. 10, when the temperature in the ion raw material supply section is lower than 500 ° C., the vapor pressure changes rapidly, so that it is stable. In order to obtain an ion beam, it is necessary to adjust the temperature inside the ion raw material supply unit to about 500 ° C. with high accuracy.

Further, when the discharge auxiliary gas is introduced into the ion generation container together with the magnesium gas through the raw material gas introduction pipe, the discharge auxiliary gas having a temperature close to room temperature flows into the raw material gas introduction pipe, so that the raw material gas introduction pipe and the discharge auxiliary are discharged. Magnesium gas may solidify and adhere to the connection portion with the tip of the gas supply pipe, blocking the introduction port of the discharge auxiliary gas supply pipe. As a result, it is difficult to extend the life of the ion source with the prior art.

Japanese Unexamined Patent Publication No. 2004-139913

The present invention has been made in consideration of such problems of the prior art, and an object of the present invention is to provide an ion source having a long life as well as being able to generate stable magnesium ions with a simple configuration. To provide.

The present invention made to solve the above-mentioned problems of the prior art has an ion generation container that generates magnesium ions by sputtering in a vacuum, a cathode electrode arranged at one end of the ion generation container, and the ion generation container. It has a repeller electrode arranged at the other end of the inside and provided so as to face the surface of the cathode electrode, and a filament arranged on the outer side of the ion generation container with respect to the cathode electrode, and the ion. A solid raw material block as a sputtering target made of a magnesium compound is provided in the production container, and the cathode electrode is heated by the energized filament to emit thermoelectrons from the electron emitting surface toward the repeller electrode. The potentials of the cathode electrode and the repeller electrode are controlled so that the thermoelectrons reciprocate between the cathode electrode and the repeller electrode, and the introduced sputter gas is decomposed by the thermoelectrons to decompose the sputter gas. It is an ion source configured to generate the plasma of the above and sputter the raw material block with the ions in the plasma to generate positively charged magnesium ions.
In the present invention, it is also effective that the raw material block is provided in the vicinity of either one or both of the cathode electrode and the repeller electrode.
In the present invention, it is also effective when the raw material block is magnesium oxide (MgO).
In the present invention, it is also effective when the raw material block is magnesium fluoride (MgF ₂ ).
The present invention is also effective when the repeller electrode is made of the magnesium compound.
Further, the present invention is an ion implantation apparatus having any of the above-mentioned ion sources and configured to irradiate and inject an ion beam emitted from the ion source onto a substrate.
Further, the present invention comprises an ion generation container that generates magnesium ions by sputtering in a vacuum, a cathode electrode arranged at one end of the ion generation container, and the cathode arranged at the other end of the ion generation container. A method of generating magnesium ions using an ion source having a repeller electrode provided so as to face the surface of the electrode and a filament arranged on the outer side of the ion generation container with respect to the cathode electrode. A solid raw material block as a sputtering target made of a magnesium compound is provided in the ion generation container, the cathode electrode is heated by the energized filament, and thermoelectrons are emitted from the electron emitting surface toward the repeller electrode. Then, the potentials of the cathode electrode and the repeller electrode are controlled so that the thermoelectrons reciprocate between the cathode electrode and the repeller electrode, and the introduced sputter gas is decomposed by the thermoelectrons to decompose the spatter. This is a magnesium ion generation method including a step of generating a gas plasma and sputtering the raw material block with the ions in the plasma to generate positively charged magnesium ions.

According to the present invention, a raw material block in a solid state as a sputtering target made of a magnesium compound is provided in an ion generation container, and the raw material block is sputtered to generate magnesium ions, which is very simple. It is possible to generate stable magnesium ions in the composition.

Further, according to the present invention, the problem of magnesium adhesion due to solidification of the gas at the introduction portion of the magnesium gas does not occur as in the conventional technique of introducing the magnesium gas into the ion generation container to generate plasma. Therefore, the life of the ion source can be extended.

Schematic configuration diagram showing the whole of the ion implantation apparatus of the present invention using the ion source of the present invention. Schematic configuration diagram showing the inside of the embodiment of the ion source according to the present invention. (A): Plan view showing the structure of the raw material block, (b): perspective view showing the structure of the raw material block (A): Plan view showing the configuration of the mounting member, (b): perspective view showing the configuration of the mounting member. (A): Plan view showing the structure of the raw material support, (b): perspective view showing the structure of the raw material support Front view showing the configuration when the raw material block is attached to the raw material support Schematic block diagram showing the inside of another embodiment of the ion source according to the present invention. Schematic block diagram showing the inside of another embodiment of the ion source according to the present invention. Schematic block diagram showing the inside of another embodiment of the ion source according to the present invention. Graph showing the saturated vapor pressure curve of magnesium

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Ion implanter>
FIG. 1 is a schematic configuration diagram showing the entire ion implantation apparatus 1 of the present invention using the ion source of the present invention.

As shown in FIG. 1, in the ion implantation device 1 of this example, the ion source 10, the traveling chamber 2, the mass spectrometer 3, the accelerator 4, the scanning device 5, and the implantation chamber 6, which will be described later, are included. It is configured by connecting in these order.

In the ion implantation device 1, the ion source 10, the traveling chamber 2, the accelerator 4, and the implantation chamber 6 are evacuated by the vacuum exhaust devices 9a to 9d, respectively.

A gas supply unit 12 is connected to the ion source 10, and the ion source 10 generates magnesium ions by sputtering using the sputter gas supplied by the gas supply unit 12.

Magnesium ions are drawn into the traveling chamber 2, travel inside the traveling chamber 2, and enter the inside of the mass spectrometer 3.

In the present embodiment, positively charged magnesium ions are mass-analyzed when passing through the inside of the mass spectrometer 3, and ions having a desired mass-to-charge ratio pass and are incident on the accelerator 4.

In the accelerator 4, the incident magnesium ions are accelerated, and when they enter the scanning device 5, the traveling direction of the ion beam is controlled by the scanning device 5 and the ion beam is incident inside the injection chamber 6.

A plurality of (two in this case) substrates 8 are arranged inside the injection chamber 6, and the ion beam is directed toward one of the plurality of substrates 8 by the scanning device 5 described above. The surface of the substrate 8 is irradiated. The surface of the substrate 8 is scanned by an ion beam and magnesium ions are injected.

<Ion source>
FIG. 2 is a schematic configuration diagram showing the inside of the embodiment of the ion source according to the present invention.

As shown in FIG. 2, the ion source 10 of the present embodiment has a tubular (here, a square cylinder) ion generation container 21, and the inside of the ion generation container 21 is a vacuum exhaust gas shown in FIG. The device 9a evacuates to a vacuum atmosphere.

The ion generation container 21 has two bottom surfaces 31 and 32, one bottom surface 31 is located at one end of the ion generation container 21 and the other bottom surface 32 is located at the other end of the ion generation container 21. , 32 are provided with mounting holes 47 and 48, respectively.

Inside the ion generation container 21, the filament 20 is arranged in the vicinity of one bottom surface 31, and the repeller electrode 23 is arranged in the vicinity of the other bottom surface 32. The filament 20 is provided on the outer side of the ion generation container 21, that is, in a vacuum atmosphere on the outer side of the ion generation container 21 with respect to the cathode electrode 22 described below.

A cathode electrode 22 is arranged inside the ion generation container 21 in the vicinity of the filament 20 between the filament 20 and the repeller electrode 23.

Both the cathode electrode 22 and the repeller electrode 23 are formed in a flat plate or a columnar shape, and the surfaces facing each other are parallel to each other in a plane. Further, the filament 20 is located on the back surface side of the cathode electrode 22.

A base plate 30 is arranged outside the ion generation container 21 and in the vicinity of the bottom surface 31. The base plate 30 is fixed to the ion generation container 21 in an insulated state.

The raw material support 26 and the electrode support 33 are inserted into the mounting holes 47 on the bottom surface 31 of the ion generation container 21, and the tip end of the electrode support 33 is arranged inside the ion generation container 21 and the other end. The root portion is fixed to the base plate 30.

The cathode electrode 22 is attached to the tip of the electrode support 33. The electrode support 33 and the cathode electrode 22 may have an integral structure.

A support rod 36 is inserted into a mounting hole 48 on the bottom surface 32 of the ion generation container 21. The tip of the support rod 36 is arranged inside the ion generation container 21, and the repeller electrode 23 is fixed.

The portion of the support rod 36 opposite to the tip is arranged outside the ion generation container 21.

The support rod 36 is fixed to the ion generation container 21 by an insulator 41, and the support rod 36 and the ion generation container 21 are insulated from each other.

The raw material support 26 is arranged between the edge of the mounting hole 47 and the electrode support 33 so as not to come into contact with the ion generation container 21 and the electrode support 33. Therefore, the raw material support 26 is fixed to the ion generation container 21 in a state where the electrical insulation between the raw material support 26 and the ion generation container 21 is maintained.

The root portion of the raw material support 26 is fixed to the base plate 30, and a solid raw material block 28 as a sputtering target, which is formed into a predetermined shape, is attached to the tip portion thereof.

In the case of the present invention, it is preferable to use magnesium oxide (MgO) as the raw material block 28.

That is, since the melting point of magnesium oxide is 2800 ° C. or higher, the raw material block 28 does not melt even when the cathode electrode 22 becomes high temperature (about 2200 ° C.) when magnesium ions are generated. ..

Since the electrode support 33 and the raw material support 26 have electrical conductivity and have the same potential as the base plate 30, both the cathode electrode 22 and the raw material block 28 have the same potential as the base plate 30.

The raw material block 28 is arranged between the side surface of the cathode electrode 22 and the side surface 25 of the ion generation container 21 so as not to come into contact with both the cathode electrode 22 and the ion generation container 21.

A planar sputtering surface 37 is provided on the portion of the raw material block 28 facing the repeller electrode 23, and the sputtering surface 37 is parallel to the surface facing the cathode electrode 22 and the repeller electrode 23 described above.

Assuming that the surface of the cathode electrode 22 facing the repeller electrode 23 is the electron emitting surface 38, the sputtered surface 37 of the raw material block 28 is located between the surface of the repeller electrode 23 facing the cathode electrode 22 and the electron emitting surface 38. ing.

That is, the sputtered surface 37 of the raw material block 28 is arranged at a position where the distance between the plane on which the sputtered surface 37 is located and the repeller electrode 23 is smaller than the distance between the electron emitting surface 38 and the repeller electrode 23. ing.

Further, the sputtering surface 37 is arranged at a position where the distance between the plane on which the sputtering surface 37 is located and the electron emitting surface 38 is smaller than the distance between the plane on which the sputtering surface 37 is located and the repeller electrode 23. There is.

The raw material block 28 has a ring shape in which a window hole 27 is formed in the center of the metal body (see FIGS. 3A and 3B), and a cathode electrode is formed in the window hole 27 formed in the central portion. The electron emitting surface 38 of 22 is arranged, and the electron emitting surface 38 is configured to be exposed in the central portion of the window hole 27.

The window hole 27 of the raw material block 28 is formed in a circular shape, the cathode electrode 22 is formed in a disk shape, and the diameter of the window hole 27 is set to be larger than the diameter of the cathode electrode 22.

A discharge power source 52, a cathode heating power source 53, and a filament heating power source 54 are arranged outside the ion generation container 21. The ion generation container 21 is electrically connected to the positive voltage terminal of the discharge power supply 52.

The base plate 30 is electrically connected to the negative voltage terminal of the discharge power supply 52. Here, they are electrically connected via the raw material support 26. Therefore, when the discharge power supply 52 operates, a negative voltage is applied to the cathode electrode 22 and the raw material block 28 with respect to the ion generation container 21.

Further, the negative voltage terminal of the discharge power supply 52 is electrically connected to the positive voltage terminal of the cathode heating power supply 53, and the negative voltage terminal of the cathode heating power supply 53 is electrically connected to one end of the filament 20. As a result, when the cathode heating power supply 53 operates, a negative voltage is applied to the filament 20 with respect to the cathode electrode 22.

One end of the filament 20 is electrically connected to the negative voltage terminal of the cathode heating power supply 53 and the negative voltage terminal of the filament heating power supply 54, and the other end of the filament 20 is electrically connected to the positive voltage terminal of the filament heating power supply 54. ing.

The cathode electrode 22, the repeller electrode 23, and the filament 20 are placed in a vacuum atmosphere, and when the filament heating power supply 54 operates and the filament 20 is energized in the vacuum atmosphere, heat is generated.

When a negative voltage is applied to the filament 20 by the cathode heating power supply 53 in this state, thermions are emitted from the filament 20 toward the cathode electrode 22, and the thermions collide with the cathode electrode 22 to heat the cathode electrode 22. To.

When the cathode electrode 22 is heated while a negative voltage is applied to the cathode electrode 22 by the discharge power supply 52 with respect to the ion generation container 21, the exposed electron emitting surface 38 of the cathode electrode 22 is transferred to the repeller electrode 23. Thermoelectrons are emitted toward and accelerated.

The repeller electrode 23 is configured to have a negative potential (floating potential in the present embodiment) equivalent to that of the cathode electrode 22. Then, the thermions (primary electrons) emitted / accelerated from the cathode electrode 22 are inverted in the flight direction by the electrostatic force and fly toward the cathode electrode 22.

The flight direction of the thermions directed toward the cathode electrode 22 is also reversed by the cathode electrode 22, and is also reversed toward the repeller electrode 23.

In this way, thermions repeatedly reciprocate between the cathode electrode 22 and the repeller electrode 23.

Outside the ion generation container 21, a magnet 58 having one of the two magnetic poles of the north and south poles directed toward the ion generation container 21 and a magnet 59 having the other pole directed toward the ion generation container 21 The magnetic field lines that are arranged and formed between the north and south poles are configured to pass through the cathode electrode 22 and the repeller electrode 23.

As a result, in the ion generation container 21, thermions wind around the magnetic field lines and move back and forth while spirally moving. By these actions, the collision probability between the argon gas in the ion generation container 21 and thermions is increased, and the plasma generation efficiency is increased.

A gas introduction hole 34 and an ion release hole 35 are provided on the side surface of the ion generation container 21.

The gas introduction hole 34 is connected to the gas supply unit 12 (see FIG. 1), and argon gas, which is a sputtering gas, is supplied from the gas supply unit 12.

The cathode electrode 22 is made of a refractory metal and is heated to a temperature of about 2200 ° C. by the filament 20.

The raw material block 28 is arranged in the vicinity of the cathode electrode 22 in a non-contact state with respect to the cathode electrode 22 and the ion generation container 21.

As a result, the raw material block 28 is heated by the heat rays emitted from the cathode electrode 22 so that heat does not flow out to the ion generation container 21, and the temperature rises.

Argon gas introduced into the ion generation container 21 generates argon plasma by thermions, and the argon plasma comes into contact with the sputtering surface 37.

Then, argon ions (Ar ⁺ ) in the argon plasma come into contact with the magnesium compound exposed on the sputtering surface 37 of the raw material block 28, and by sputtering, Mg atoms are emitted into the discharge chamber, and thermions emitted from the cathode are emitted. Positively charged magnesium ions (Mg ⁺ ) are generated from the emitted Mg atoms by the electron impact method used.

A flat plate-shaped extraction electrode 24 to which a negative voltage is applied to the ion generation container 21 is arranged in the vicinity of the ion emission hole 35 outside the ion generation container 21, and is generated inside the ion generation container 21. The positively charged magnesium ions are attracted to the extraction electrode 24 by the electric field formed by the extraction electrode 24, are extracted from the ion discharge hole 35 to the outside of the ion generation container 21, and pass through the central hole 39 of the extraction electrode 24. It is incident on the inside of the traveling chamber 2 shown in FIG.

FIG. 3A is a plan view showing the structure of the raw material block, and FIG. 3B is a perspective view showing the structure of the raw material block.

FIG. 4A is a plan view showing the configuration of the mounting member, and FIG. 4B is a perspective view showing the configuration of the mounting member.

FIG. 5A is a plan view showing the structure of the raw material support, and FIG. 5B is a perspective view showing the structure of the raw material support.

FIG. 6 is a front view showing a configuration when the raw material block is attached to the raw material support.

Both the electrode support 33 and the raw material support 26 of this example have a cylindrical shape, and the diameter of the electrode support 33 is smaller than the diameter of the raw material support 26 (see FIG. 2).

Here, the electrode support 33 and the raw material support 26 are arranged so that the central axes coincide with each other, and the electrode support 33 is arranged inside the hollow of the raw material support 26 and fixed to the base plate 30 respectively.

As shown in FIGS. 3A and 3B, the raw material block 28 is formed with an insertion hole 29a into which the screw 43 shown in FIG. 6 can be inserted.

The mounting member 44 is a flat plate-shaped member for mounting the raw material block 28 on the raw material support 26, and as shown in FIGS. 4A and 4B, the mounting member 44 has a screw groove formed on the inner peripheral surface. The screw holes 29b are provided.

The mounting member 44 is formed with a mounting portion 45 which is a semicircular notch.

The size of the diameter of the semicircle of the mounting portion 45 is the same as or slightly larger than the outer diameter of the raw material support 26. Therefore, the mounting member 44 can be fitted into the raw material support 26 so that the raw material support 26 is arranged at the position of the mounting portion 45 of the mounting member 44.

As shown in FIGS. 5A and 5B, a protruding portion 46 is provided at the tip of the raw material support 26. The protruding portion 46 is perpendicular to the side surface of the raw material support 26 and protrudes outward, and is formed in a flange shape, for example.

In the present embodiment, the repeller electrode 23 is arranged at a position below the ion generation container 21, and the raw material support 26 is vertically arranged so that the protruding portion 46 is located at the lower end of the raw material support 26.

When the mounting member 44 is mounted on the raw material support 26, the diameter of the semicircle of the mounting portion 45 is set so as to ride on the protruding portion 46 of the raw material support 26.

In order to mount the raw material block 28 on the raw material support 26, the raw material block 28 is brought into contact with the surface of the protruding portion 46 of the raw material support 26 facing the repeller electrode 23, and the protruding portion 46 is mounted on the raw material block 28. As shown in FIG. 6, the screw 43 is inserted into the insertion hole 29a of the raw material block 28, and the tip of the screw 43 is screwed into the screw hole 29b of the mounting member 44 in a state of being arranged between the member 44 and the member 44.

Then, the screw 43 is rotated, a force is applied in the direction of approaching the raw material block 28 and the mounting member 44, the screw head portion of the screw 43 is brought into contact with the raw material block 28, and the raw material block 28 and the mounting member 44 collide with each other. The shape portion 46 is sandwiched and the raw material block 28 is fixed to the raw material support 26.

According to the present embodiment described above, the raw material block 28 in a solid state as a sputtering target made of a magnesium compound is provided in the ion generation container 21, and the raw material block 28 is sputtered to generate magnesium ions. As a result, stable magnesium ions can be generated with a very simple structure.

Further, according to the present embodiment, there is a problem of magnesium adhesion due to solidification of the gas in the introduction portion of the magnesium gas, as in the conventional technique of introducing the magnesium gas into the ion generation container to generate plasma. Since it does not occur, the life of the ion source can be extended.

7 to 9 are schematic configuration diagrams showing the inside of another embodiment of the ion source according to the present invention. Hereinafter, the parts corresponding to the above-described embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

In the ion source 10A of the embodiment shown in FIG. 7, the raw material block 28A is provided in the vicinity of the repeller electrode 23A, and the raw material block is not provided in the vicinity of the cathode electrode 22.

In the present embodiment, the cup-shaped repeller electrode 23A having the wall portion 23a is provided, and the raw material block 28A is arranged on the repeller electrode 23A.

The repeller electrode 23A is provided so that its bottom 23b faces the cathode electrode 22, and a raw material block 28A made of a magnesium compound is arranged in the bottom 23b.

In the case of the present invention, as the raw material block 28A, in consideration of the respective melting points, it is preferable to use magnesium fluoride (MgF ₂ ) having a melting point of about 1200 ° C. in addition to the above-mentioned magnesium oxide (MgO).

The reason for this is that the temperature of the repeller electrode 23A is considerably lower (about 1000 ° C.) than the temperature of the cathode electrode 22 when magnesium ions are generated.

In addition, when magnesium fluoride (MgF ₂ ) is used as the raw material block 28A, there is no oxygen supply from the raw material block 28A, so that problems due to oxidation of the surrounding environment (corrosion, film peeling, etc.) do not occur, and the footwear. It can be said that it is more preferable in terms of the effect that the maintenance cycle can be extended even in consideration of the occurrence of problems due to the conversion.

In the present embodiment, for example, when the ion generation container 21 is arranged so that the cathode electrode 22 is on the upper side and the repeller electrode 23A is on the lower side, the raw material block 28A does not fall off from the repeller electrode 23A. , It is sufficient to place it on the bottom 23b of the repeller electrode 23A as it is.

On the other hand, when the ion generation container 21 is arranged so that the repeller electrode 23A is on the upper side, or when the ion generation container 21 is arranged so that the cathode electrode 22 and the repeller electrode 23A are at the same height position. For example, the raw material block 28A may be fixed to the bottom 23b of the repeller electrode 23A with a screw.

Even with such an embodiment, the same effect as that of the above-described embodiment can be exhibited.

In the ion source 10B of the embodiment shown in FIG. 8, the raw material block 28 shown in FIG. 2 is provided in the vicinity of the cathode electrode 22, and the raw material block 28A shown in FIG. 7 is provided in the vicinity of the repeller electrode 23A. Is.

According to this embodiment, the efficiency of magnesium ion generation can be improved.

In the ion source 10C of the embodiment shown in FIG. 9, the repeller electrode 23C itself is made of a magnesium compound.

In the case of this embodiment, either magnesium oxide or magnesium fluoride described above can be used as the magnesium compound.

Even with such an embodiment, the same effect as that of the above-described embodiment can be exhibited.

The present invention is not limited to the above-described embodiment, and various modifications can be made.

For example, in the embodiment shown in FIG. 2, a ring-shaped raw material block 28 is provided in the vicinity of the cathode electrode 22, but the present invention is not limited to this, and the surface of the cathode electrode 22 facing the repeller electrode 23 The raw material block 28 can also be arranged in.

In this case, it is preferable to adjust the shape and size of the raw material block 28 so that most of the surfaces of the cathode electrode 22 facing the repeller electrode 23 are not covered by the raw material block 28.

Further, in the embodiment shown in FIG. 9 in which the repeller electrode 23C made of the magnesium compound is provided, the raw material block 28A made of the magnesium compound shown in FIG. 7 is further arranged on the surface of the repeller electrode 23C facing the cathode electrode 22. You can also do it.

1 ... Ion implantation device 10 ... Ion source 12 ... Gas supply unit 20 ... Filament 21 ... Ion generation container 22 ... Cathode electrode 23 ... Repeller electrode 26 ... Raw material support 28, 28A ... Raw material block 37 ... Sputter surface 38 ... Electron emission surface

Claims (7)

An ion generation container that generates magnesium ions by sputtering in a vacuum,
A cathode electrode arranged at one end in the ion generation container and
A repeller electrode arranged at the other end of the ion generation container and provided so as to face the surface of the cathode electrode.
It has a filament arranged on the outer side of the ion generation container with respect to the cathode electrode.
A solid raw material block as a sputtering target made of a magnesium compound is provided in the ion generation container, and is also provided.
The cathode electrode is heated by the energized filament to emit thermoelectrons from the electron emitting surface toward the repeller electrode, and the thermoelectrons reciprocate between the cathode electrode and the repeller electrode. The potentials of the cathode electrode and the repeller electrode are controlled, the introduced sputter gas is decomposed by the thermoelectrons to generate plasma of the sputter gas, and the raw material block is sputtered by the ions in the plasma to have a positive charge. An ion source that is configured to produce magnesium ions. The ion source according to claim 1, wherein the raw material block is provided in the vicinity of either one or both of the cathode electrode and the repeller electrode. The ion source according to any one of claims 1 or 2, wherein the raw material block is magnesium oxide (MgO). The ion source according to any one of claims 1 to 3, wherein the raw material block is magnesium fluoride (MgF ₂ ). The ion source according to any one of claims 1 to 4, wherein the repeller electrode is made of the magnesium compound. The ion source according to any one of claims 1 to 5 is provided.
An ion implantation device configured to irradiate a substrate with an ion beam emitted from the ion source and inject it. An ion generation container that generates magnesium ions by sputtering in a vacuum, a cathode electrode arranged at one end of the ion generation container, and a cathode electrode arranged at the other end of the ion generation container and facing the surface of the cathode electrode. A method of generating magnesium ions using an ion source having a repeller electrode provided as described above and a filament arranged on the outer side of the ion generation container with respect to the cathode electrode.
A solid raw material block as a sputtering target made of a magnesium compound is provided in the ion generation container.
The cathode electrode is heated by the energized filament to emit thermoelectrons from the electron emitting surface toward the repeller electrode, and the thermoelectrons reciprocate between the cathode electrode and the repeller electrode. The potentials of the cathode electrode and the repeller electrode are controlled, the introduced sputter gas is decomposed by the thermoelectrons to generate plasma of the sputter gas, and the raw material block is sputtered by the ions in the plasma to have a positive charge. A method for producing a magnesium ion, which comprises a step of producing a magnesium ion.

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