JPH08148104A - Ion source device - Google Patents

Abstract

PURPOSE: To draw out a high quality ion beam by forming a beam crossing a water cooling pipe on an electrode surface in an ion source device, thereby preventing warping of an electrode. CONSTITUTION: In an ion source device in which ion beam is drawn out from plasma in a plasma chamber with an draw-out electrode, a beam 17 is fixed on face of an accelerating electrode 7 on the side of a plasma chamber in a direction perpendicular to a water cooling pipe 13 by welding, soldering or with a screw. Accordingly, even when warping/deformation of the electrode are caused due to heat flowing into the electrode 7, the warping/deformation is prevented by the beam 17. The beam 17 may be formed not only in direction perpendicular but also obliquely to a water cooling pipe 13. The beam 17, then, may also be formed not only in an accelerating electrode, but in a decelerating electrode and an earthing electrode, or otherwise only in any one electrode alone. The beam 17 may be formed not only singly but also plurally in crossing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion source device used in an IBS device, an IVD device, etc., in which thermal distortion of electrodes is eliminated.

[0002]

2. Description of the Related Art A conventional ion source device of this kind is shown in FIGS. In those figures, 1
Is a container, 2 is a plasma chamber formed by the container 1, and 3 is a filament introduced into one side of the container 1 through an insulating support 4, and is heated to a high temperature by a filament power source to emit thermoelectrons. Reference numeral 5 denotes a gas introduction port formed on one side of the container 1, and a gas of a required type and amount is introduced into the plasma chamber 2 from the gas introduction port 5.

Reference numeral 6 denotes an extraction electrode provided in an opening at a position facing the filament 3 of the container 1, and comprises an acceleration electrode 7, a deceleration electrode 8 and a ground electrode 9, and each electrode 7, 8, 9 is made of an insulator. Is supported through. Reference numeral 10 denotes a plurality of magnets arranged on the outer surface of the container 1, and adjacent magnets 10 have different polarities to form a cusp magnetic field.

Reference numeral 11 denotes a large number of holes formed in each of the electrodes 7, 8 and 9, reference numeral 12 denotes two bulging portions formed on the surface of the acceleration electrode 7 on the plasma chamber 2 side, and reference numeral 13 denotes a bulging portion 12. Reference numeral 15 denotes a water-cooling pipe embedded in the groove 14, and reference numeral 15 denotes a long lid plate that covers the water-cooling pipe 13 and is attached to the bulging portion 12.

The thermoelectrons from the filament 3 are accelerated with the container 1 and collide with the gas from the gas inlet 5, plasma 16 is generated, and the plasma 16 is generated by the cusp magnetic field of each magnet 10. The ion beam is confined in the center of the container 1 and the ion beam is extracted through the hole 11 by the extraction electrode 6.

At this time, the acceleration electrode 7 in contact with the plasma 16
Is sputtered from the plasma 16, and the deceleration electrode 8 and the ground electrode 9 which are not in direct contact with the plasma 16 are also sputtered by a part of the extracted ion beam, so that the electrodes 7, 8 and 9 are considerably sputtered. Heat flows in. Thus, the water-cooled pipe 13 absorbs the inflowing heat to prevent the temperature rise of the electrodes 7, 8, 9 and prevent the holes 11 of the electrodes 7, 8, 9 from being displaced due to thermal strain.

[0007]

In the case of the conventional temperature rise prevention means using the water-cooled pipe 13, when the plasma density becomes high or the ion beam amount becomes large, a certain temperature rise cannot be avoided and heat is applied to the electrodes. Distortion occurs, the electrodes warp with the position of the water cooling pipe 13 as a boundary, and the holes of each electrode are displaced. Especially when the area of the electrode is large or the thickness of the electrode is thin, the electrode warps, and a high-quality ion beam There is a problem that you can not pull out. The present invention has been made in consideration of the above points, and an object of the present invention is to provide an ion source device capable of preventing a warp of an electrode and extracting a high quality ion beam.

[0008]

In order to solve the above problems, the ion source device of the present invention is an ion source device in which an ion beam is extracted from plasma in a plasma chamber by an extraction electrode, and a water cooling pipe is provided in the electrode. A beam intersecting with the water cooling pipe is formed on the surface of the electrode.

[0009]

In the ion source device of the present invention constructed as described above, since the beam intersecting the water cooling pipe is formed on the surface of the extraction electrode, the temperature rise of the electrode can be sufficiently prevented by cooling with the water cooling pipe. Therefore, even if heat is introduced, the electrodes are not distorted or warped, the holes of the electrodes are not displaced, and a high-quality ion beam can be extracted.

[0010]

EXAMPLES Examples will be described with reference to FIGS. 1 and 2. In these figures, the same reference numerals as those in FIGS. 3 and 4 indicate the same or corresponding elements. First, in FIG. 1 showing one embodiment, a point different from FIG. 4 is that the surface of the acceleration electrode 7 on the plasma chamber 2 side is orthogonal to the water cooling pipe 13.
The beam 17 is fixed by means such as welding, brazing or screwing.

Therefore, even if the heat flowing into the electrode 7 causes distortion or warpage, the beam 17 prevents the distortion or warpage. Next, FIG. 2 showing another embodiment is one in which the beam 17 of FIG. 1 is formed integrally with the electrode 7. In this case, the electrode 7 and the beam 17 of FIG. The heat distortion that occurs when the beam 17 is fixed by welding or brazing does not occur, and measures such as removing the heat distortion are unnecessary, and the beam 17 can be formed at low cost. In addition,
The beam 17 may be formed not only in a direction orthogonal to the water-cooling pipe 13 but also obliquely, and may be formed not only in one line but also in a plurality of lines. The beam 17 may be formed not only on the acceleration electrode 7 but also on the deceleration electrode 8 or the ground electrode 9, or may be formed only on any one of the electrodes 7, 8, 9.

[0012]

Since the present invention is configured as described above, it has the following effects. In the ion source device of the present invention, since the beam 17 that intersects the water cooling pipe 13 is formed on the surface of the extraction electrode, cooling with the water cooling pipe 13 cannot sufficiently prevent the temperature rise of the electrode, and the heat inflow does not occur. Even if there is, the electrode is not distorted or warped, the position shift of the hole 11 of each electrode can be prevented, and a high-quality ion beam can be extracted.

[Brief description of drawings]

1A, 1B and 1C are a front view, a cut bottom view and a cut side view of an embodiment of the present invention.

2A, 2B and 2C are a front view, a cut bottom view and a cut side view of another embodiment of the present invention.

FIG. 3 is a cut side view of a conventional ion source device.

4A and 4B are a front view and a cut bottom view of the electrode of FIG.

[Explanation of symbols]

 2 Plasma chamber 6 Extraction electrode 7 Accelerating electrode 13 Water cooling pipe 16 Plasma 17 Beam

Claims (1)

[Claims] 1. An ion source device in which an ion beam is extracted from plasma in a plasma chamber by an extraction electrode and a water-cooled pipe is provided on the electrode, wherein a beam intersecting the water-cooled pipe is formed on a surface of the electrode.