JPH05225924A - Ion beam generator - Google Patents

Abstract

PURPOSE:To provide an ion beam generator which alone can generate plural ion beams with high efficiency. CONSTITUTION:A cylindrical anode 3, a first extracting-electrode 4 and a second extracting electrode 5 are concentrically arranged one by one from inside, placing a hot cathode 2 in the center. Radiation holes 11, 12, and 13 boring through them in the same rows are established at plural places in their circumferential direction, and the inside of the cylindrical anode 3 in the center is formed into the plasma producing chamber 10 of target gas, to which lines of magnetic force are applied by an external magnet 8 so as to confine the plasma to the chamber. Target ions are extracted out of the plasma through the radiation holes 11, 12, and 13 as ion beams by the first extracting electrode 4 and the second extracting electrode 5. The plasma can be produced also by microwave.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to surface layer modification, surface treatment,
The present invention relates to an ion beam generator useful as a thin film forming apparatus and the like.

[0002]

2. Description of the Related Art In general, when an ion beam is applied to a workpiece, the floating energy of the ion beam changes to thermal energy, and melting and evaporation occur on the surface of the workpiece.
It is used for processing of workpieces such as polishing, etching, surface treatment, etc., and in recent years, impurity injection into semiconductors such as IC circuits, surface modification by ion implantation into metal surface, oxide film and nitride film. It is used for surface layer processing such as creation of.

Conventionally, in an ion beam generator, a space provided with a hot cathode is surrounded by an anode, and a space (plasma generating chamber) surrounded by the anode is discharged to generate plasma containing target ions. Shape, and instead of providing the above-mentioned hot cathode and anode, there is a microwave waveform that introduces a microwave into a space (plasma generation chamber) surrounded by a conductor to generate plasma. For example, an extraction with a negative bias voltage applied. Only positive ions are taken out from the plasma by the electrodes and accelerated by high pressure to form an ion beam. As an ion source of interest, there are an ion source dedicated to gas ions and a type of vaporizing a substance such as a metal in a crucible and turning it into a plasma in a plasma generation chamber.

[0004]

However, the conventional ion beam generator has a structure in which one ion beam is emitted from one device. For this reason, in order to simultaneously modify the surface layer of a plurality of materials to be processed by ion implantation or perform surface layer processing by film formation, a number of beam generators corresponding to the materials to be processed are required, and the ion beam generation is required. Efficiency and 1
The number of units processed per unit time, that is, the productivity, was low when viewed from the ion beam generators on the table.

Therefore, the present invention has been made to solve the above-mentioned problems, and a plurality of ion beams can be generated by a common constituent element constituting one unit, and therefore, the ion beam generation efficiency is high, An object of the present invention is to provide an ion beam generator capable of increasing the number of treatments per unit time viewed from the apparatus.

[0006]

In order to achieve the above object, the first embodiment of the ion beam generator of the present invention comprises a cylindrical anode and an extraction electrode which are concentrically and sequentially arranged from the inside centering on a hot cathode. These anodes and extraction electrodes are provided with radiation holes penetrating in the same direction in the radial direction at a plurality of locations in the circumferential direction, and the space in the central cylindrical anode is discharged to plasmanize the target ionized gas. In addition to the above-mentioned plasma generation chamber, an external magnet for confining the plasma by providing magnetic lines of force is provided in the plasma generation chamber, and target ions are extracted from the plasma in the plasma generation chamber as ion beams from the radiation holes.

In the second embodiment, a plasma generation chamber for introducing microwaves into a desired ionized gas to form a plasma is centered, and a cylindrical plasma generation chamber and an extraction electrode are concentrically and sequentially arranged from the inside. The plasma generation chamber and the extraction electrode are provided with radial holes penetrating in the same direction in the radial direction at a plurality of locations in the circumferential direction, and an external magnet for confining the plasma by giving magnetic lines of force is provided in the central plasma generation chamber. The structure is such that the atoms turned into plasma by (1) are extracted as an ion beam from the radiation hole.

[0008]

The target ionized gas is turned into plasma by the discharge in the central cylindrical anode or by the microwave introduced into the plasma generation chamber and is confined in the magnetic field created by the external magnet. Are drawn by the surrounding extraction electrodes. At this time, since the anode and the extraction electrode are provided with radial holes penetrating in the same direction in the radial direction at a plurality of positions in the circumferential direction, the ion beam is radially radiated from these radial holes.

When generating a plurality of these ion beams, the number of plasma forming chambers is one, and the extraction electrodes in the periphery are also common, so that the ion beam generation efficiency is high, and the number of treatments per unit time seen from the apparatus is high. Can be increased. Further, since an ion beam is radially generated in the surroundings, it is suitable for the inner surface treatment of a tubular material such as a pipe and a bearing.

[0010]

An embodiment of the present invention will be described with reference to the accompanying drawings.

1 and 2 show an ion beam generator 1
Is an embodiment of the hot cathode discharge type. The ion beam generator 1 has a configuration in which a cylindrical anode 3, a first extraction electrode 4, and a second extraction electrode 5 are concentrically and sequentially arranged from the inner side around a hot cathode 2. Both end faces of the cylindrical shape of the anode 3, the extraction electrodes 4 and 5 are supported by an insulating ring 6, and an insulating plate 7 for supporting the hot cathode 2 in the center is placed and fixed on the insulating ring 6. ing. Therefore, the hot cathodes 2 are supported by both insulating plates 7 and hang down one by one from both end surfaces of the cylindrical anode 3, so that a total of two hot cathodes are provided. Reference numeral 8 is an external magnet for confining plasma by magnetic lines of force, which is arranged so as to surround a cylindrical space (chamber) formed by the anode 3, the extraction electrodes 4, 5 and the insulating plate 7 orthogonally thereto. ing. Reference numeral 9 denotes a gas inlet for introducing a working gas (here, discharge gas) such as Ar and a target ionized gas into a cylindrical discharge space (plasma generation chamber) 10 formed by the anode 3 and the insulating plate 7.

The ionized gas introduced through the inlet 9 is
By the discharge between the hot cathode 2 and the anode 3 to which a positive voltage is applied,
It is plasmatized (ionized) in the plasma generation chamber 10 and is confined in the mirror magnetic field formed by the magnet 8. In order to radiate only the desired positive ions as a beam from this plasma, the anodes 3, the extraction electrodes 4 and 5 have the radiation holes 11, 12 penetrating in the same radial direction at a plurality of positions in the circumferential direction. 13 are provided in an appropriate number in the axial direction, and a negative bias voltage is applied to the extraction electrode 5 so that the extraction electrode 5 functions as a plasma grid together with the extraction electrode 4. For this reason,
The ions pass through the radiation holes 11, 12 and 13, are focused by the beam extraction electrodes 4 and 5 and are further accelerated, and are extracted as an ion beam 14 out of the chamber.

Although the two extraction electrodes 4 and 5 are provided in the embodiment, the number of extraction electrodes may be one or two or more and any desired number may be provided. Further, the magnet 8 may be arranged in any way as long as a magnetic field capable of confining the plasma is formed in the plasma generation chamber 10, and for example, a cusp magnetic field may be formed.

The ion beam generator 1 described with reference to FIG.
Has a configuration in which the ions generated in the plasma generation chamber 10 are radially radiated by the extraction electrodes 4 and 5 outside the plasma generation chamber 10, and by utilizing the characteristics thereof, it can be applied to various uses.

FIG. 3 shows an application example which makes the best use of the feature that the ion beam generator 1 can be directly arranged inside a tubular material to be treated such as a pipe and a bearing. That is, the tubular material 15 such as a pipe and a bearing is placed on the rotary table 16 so as to rotate, and the tubular material 15 is processed.
The ion beam generator 1 is disposed inside the bearing 17 to configure an apparatus for performing an inner layer reforming process by ion implantation. The tubular material 17 is rotated around the ion beam generator 1 together with the rotary table 16,
Ions are implanted into the inner surface of the ion beam generator 1 by a plurality of ion beams emitted from the ion beam generator 1. By providing a moving device that moves the tubular material 17 to be processed in the axial direction with respect to the ion beam generator 1 together with the rotary table 16, the material to be processed 15 can be moved from near one end to near the other end. Ions can be implanted into the entire inner surface of the material 15 to be processed in the axial direction. As the implanted ions,
To improve wear resistance or corrosion resistance, for example, nitrogen (N), chromium oxide or the like is used.

When applied to a surface treatment apparatus by sputtering, for example, one ion beam generator 1
It is possible to adopt a configuration in which a plurality of ion beams generated from the above are made to enter the respective pipes prepared for the respective beams from the axial direction, and the sputtering material provided in these pipes is irradiated. Here, titanium nitride (TiN) is applied to the inner surface of the pipe.
If a film is to be generated, the ion beam generator 1
Nitrogen (N) is used as the ionic species of
The sputter material consisting of i) is used. Titanium atoms knocked out from the sputter material react with nitrogen, and the reaction product (TiN) adheres to the inner surface of the pipe to coat the TiN film. Since the TiN film is excellent in wear resistance and corrosion resistance, the TiN film is generated on the inner surface of the pipe or the like in which the corrosive fluid such as the plant flows and the pipe in the reactor. The safety can be improved.

In the above embodiment, the case of the hot cathode type has been described, but the present invention is not limited to this, and a micro-waveform ion beam generator is constructed in the same manner as the hot cathode type embodiment. You can also do it. That is, FIG.
As shown in FIG. 1, a plasma generation chamber is formed by a space surrounded by a cylindrical conductor, instead of the plasma generation chamber 10 by the hot cathode 2 and the anode 3 in FIG.
8 is introduced, and the target ionized gas is turned into plasma by the microwave 18 instead of the discharge. Then, a cylindrical first extraction electrode and a second extraction electrode are arranged concentrically and sequentially outwardly around the plasma generation chamber, and magnetic lines of force are applied to the plasma generation chamber outside the cylindrical chamber to confine the plasma. An external magnet 8 is provided. In this case, when the external magnet 8 is arranged at the same position as in FIG. 1, it is composed of an annular coil having a hole coaxial with the chamber, and the ionized gas and the microwave 18 are introduced into the annular coil coaxially. Good. In the plasma generation chamber, the first extraction electrode and the second extraction electrode, as in the case of FIG. 2,
Radiation holes penetrating in the same direction in the radial direction are provided at a plurality of positions in the circumferential direction, and only the target ions in the plasma in the plasma generation chamber are ionized by the first extraction electrode and the second extraction electrode as ion beams through the emission holes. Withdraw.

[0018]

In summary, according to the ion beam generator of the present invention, the desired ion beam can be emitted radially. When generating a plurality of these ion beams, the number of plasma forming chambers is one and the surrounding extraction electrodes are also common, so the ion beam generation efficiency is high and the number of treatments per unit time viewed from the device is increased. You can Further, since an ion beam is radially generated in the surroundings, it is suitable for the inner surface treatment of a tubular material such as a pipe and a bearing.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an ion beam generator showing an embodiment of the present invention.

2 is a sectional view taken along the line II-II of the ion beam generator of FIG.

FIG. 3 is a diagram showing an example of application to an inner surface treatment of a cylindrical material to be treated.

FIG. 4 is a schematic view of an ion beam generator showing another embodiment of the present invention.

[Explanation of symbols]

 1 Ion Beam Generator 2 Hot Cathode 3 Anode 4 First Extraction Electrode 5 Second Extraction Electrode 6 Insulating Ring 7 Insulating Plate 8 External Magnet 9 Gas Inlet 10 Plasma Generation Chamber 11, 12, 13 Radiating Hole 14 Ion Beam 15 Cylindrical Body Material 16 rotary table 17 bearing 18 microwave

Claims (2)

[Claims] 1. A cylindrical anode and an extraction electrode are concentrically and sequentially arranged from the inside centering on a hot cathode, and the anode and the extraction electrode are radiated through a plurality of circumferential positions in the same radial direction. A hole is provided to form a plasma generation chamber that discharges the space inside the central cylindrical anode to turn the target ionized gas into plasma, and an external magnet that provides magnetic lines of force to confine the plasma inside the plasma generation chamber is provided. An ion beam generator characterized in that target ions are extracted from the plasma in the generation chamber as an ion beam from the radiation hole. 2. A cylindrical plasma generation chamber and an extraction electrode are concentrically and sequentially arranged from the inside centering on a plasma generation chamber that introduces microwaves into a desired ionized gas to form a plasma. The extraction electrode is provided with radial holes penetrating in the same direction in the radial direction at a plurality of positions in the circumferential direction thereof, and an external magnet for confining the plasma by providing magnetic field lines in the central plasma generation chamber is provided.
An ion beam generator characterized in that target ions are extracted from the plasma in a plasma generation chamber as an ion beam from the radiation hole.