JPH0574901B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an ion source, and more particularly to an ion source including at least two stacked electrodes for extracting ions.

[Background of the invention]

Regarding the electrodes of conventional ion sources, for example, as described in JP-A-57-78800, several rectangular, circular, or spherical electrodes are stacked in the direction in which ions are accelerated. Ta.

However, as ion sources become more diverse, larger in size, and a variety of electrode materials are used, support structures become difficult due to thermal deformation of the electrodes, and large electrode materials cannot be manufactured. There are drawbacks such as the need to dismantle the entire electrode during maintenance, which requires a long time for maintenance, but the above-mentioned known examples did not take this point into consideration.

[Purpose of the invention]

The present invention has been made in view of the above points, and its purpose is to provide an electrode with a large area and minimal thermal deformation even as the size of the electrode increases and a wide variety of electrode materials are used. Of course, it is an object of the present invention to provide an ion source that does not require the manufacture of large electrode materials and allows maintenance of the electrodes to be carried out in a short period of time.

[Summary of the invention]

There are at least two electrodes for accelerating ions.
An insulator is held between the electrodes, and a voltage is applied to accelerate the ions.
The temperature rises due to the heat radiated by the filament and the heat generated by the collision of ions, but this temperature rise leads to deformation of the electrode, and therefore, the directionality of the ions deteriorates.

This means that the larger the diameter, the greater the amount of deformation, and the larger the diameter, the more problems arise with the material of the electrode, making it impossible to manufacture it, and the entire electrode must be disassembled for maintenance. It was necessary and time consuming.
Therefore, each stacked electrode is divided into a plurality of blocks, and each block is combined with each electrode to become independent. Therefore, it is possible to obtain an electrode with a large area and less deformation. Needless to say, the structure allows electrodes to be manufactured and disassembled for each block, thereby achieving the above-mentioned purpose.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

As shown in the figure, the plasma chamber 1 has a current introduction terminal 3 for introducing a filament current to heat the filament 2, and a gas introduction port 4 for introducing a gas such as hydrogen or argon. On the other hand, an acceleration electrode 5 for accelerating ions, a deceleration electrode 6,
The ground electrodes 7 are fixed to an electrode support fitting 9 while maintaining a gap between each electrode with an insulating spacer 8 made of ceramic or the like.

In this embodiment, each electrode is divided into a plurality of blocks in a plane perpendicular to the ions to be accelerated, as shown in FIG. , 7 are combined and independent.

In this way, since the electrode is divided into a plurality of blocks, an ion source electrode can be obtained in which thermal deformation within each block is small. In addition, even if the size is increased, there is no need to manufacture a large integrated electrode.
Manufacturing is facilitated because each block can be manufactured individually. Furthermore, at the time of maintenance, only the necessary blocks can be removed without having to solve the entire electrode, which has the effect of shortening the maintenance time.

〔Effect of the invention〕

According to the ion source of the present invention as described above, each of the at least two stacked electrodes for extracting ions from the plasma chamber is divided into a plurality of blocks, and each divided electrode block is formed into a block in which each electrode is assembled. Because they are combined and independent, it is possible to obtain large-area electrodes with small thermal deformation even when larger sizes and a variety of electrode materials are used, and it is also possible to manufacture large electrode materials. It is possible to obtain an ion source that does not require maintenance of electrodes and can be performed in a short time.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of an ion source showing an embodiment of the present invention, and FIG. 2 is a sectional view taken along line A--A in FIG. 1. 1... plasma chamber, 2... filament, 3...
...Current introduction terminal, 4...Gas introduction port, 5...Acceleration electrode, 6...Deceleration electrode, 7...Grounding electrode, 8...
Insulating spacer, 9...electrode support fitting, 10...block electrode.

Claims (1)

[Scope of Claims] 1. An ion source comprising a plasma chamber for introducing gas, etc. and turning the gas, etc. into plasma, and at least two stacked electrodes for extracting ions from the plasma chamber, comprising at least An ion source characterized in that each of the two electrodes stacked one on top of the other is divided into a plurality of blocks, and each block of divided electrodes is a combination of the two electrodes and is independent.