JPH01698A - plasma x-ray source - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to plasma X-ray sources.

[Conventional technology]

The vacuum trigger gap of a vacuum trigger gap device, which has an external conductor, a vacuum trigger gap, etc., has little electrode wear and can carry a large current, so it has been conventionally used as a switch in a pulsed large current circuit. A conventional vacuum trigger gap, as described in Japanese Unexamined Patent Publication No. 48-5545, is constructed by providing opposing main electrodes in a vacuum container, and providing a trigger electrode on one of the main electrodes. A pulse source is applied between the electrode and the main ff1ti to cause a discharge, thereby causing a discharge between the main electrodes.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology has a problem that it cannot be applied as a high-speed pulse source of a plasma X-ray source because no consideration is given to reducing the inductance of the vacuum trigger gap of the vacuum trigger gap device. Generally, for plasma X-ray sources, an electric field distortion type trigger gap described in Japanese Patent Application Laid-Open No. 173496/1983 is used. Since the electric field distortion type is large in size and has a large switch inductance for high voltage and large current conduction, a large number of them are used in parallel to achieve a single current carrying capacity and low inductance. Although the vacuum trigger gap is suitable for passing high voltage and large current, it is expensive due to restrictions on the materials used, including heating and degassing treatment at about 300°C. Also, when applied to a plasma X-ray source, the discharge is repeated several times per second.

It had a limited lifespan and needed to be easily replaced.

The present invention has been made in view of the above points.

Plasma
Its purpose is to provide a radiation source.

[Means for solving problems]

The above purpose is achieved by providing an external conductor with an external lead-out terminal at at least one end of both terminals, disposing the external conductor coaxially with the vacuum trigger gap on the outer periphery of the vacuum trigger gap, and forming the vacuum trigger gap in a detachable manner. , achieved.

[Effect]

Since the outer conductor with an external lead terminal provided on at least one end thereof and the vacuum trigger gap with a movable current collector provided on at least one end thereof are arranged coaxially, a coaxial electrode is formed. , the inductance of the vacuum trigger gap device can be reduced. In addition, since the vacuum trigger gap that forms the center conductor is made removable, you only need to replace the vacuum trigger gap of the center conductor when the vacuum trigger gap reaches the end of its lifespan, making maintenance management easier and reducing replacement work time. Can be shortened. Since the vacuum trigger gap of the center conductor is sealed after vacuum heating and degassing treatment, metals and insulating materials that can be used at room temperature can be used for the parts other than the vacuum trigger gap.

〔Example〕

The present invention will be explained below based on the illustrated embodiments.

FIG. 1 shows an embodiment of the invention. As shown in the figure, the plasma X-ray source is connected to capacitor bank 1.
and a vacuum trigger gap device 3 that forms a discharge circuit together with the discharge tube 2 for generating X-rays. And the vacuum trigger gap device 3 connects the outer conductor 4 and the vacuum trigger gap 5.
The vacuum trigger gap 5 has a pair of opposing electrodes 6.7 provided in the vacuum container, and a pair of opposing electrodes 6.7 provided in the vacuum container.
．． and a trigger electrode 8 provided on at least one of the electric wires 6 of 7. In this embodiment, in the plasma X-ray source configured as described above, the external conductor 4 is provided with an external lead terminal 9 at at least one end of both ends thereof, and an external lead terminal 9 is provided on the outer periphery of the vacuum trigger gap 5 coaxially with the vacuum trigger gap 5. At the same time, the vacuum trigger gap 5 was formed to be detachable. By doing this, the vacuum trigger gap device has a low inductance and maintenance management is easy, thereby obtaining a plasma X-ray source that can reduce the inductance of the vacuum trigger gap device and facilitate maintenance management. 6 i.e. capacitor bank 1.
Vacuum trigger gap device 3. A plasma X-ray source has a discharge circuit formed from an X-ray generating discharge tube 2 and the like, and generated X-rays are emitted into an exposure apparatus 10 for exposure. The configuration of the discharge tube 2 for generating X-rays and the exposure device 10 is disclosed in Japanese Patent Application Laid-Open No. 1986-
151945 is referred to. The vacuum trigger gap device 3 has an outer conductor 4 and opposing electrodes 6, 7 and a trigger electrode 8, but the opposing electrodes 6, 7
is insulated by an insulator 11, and the trigger electrode 8 is insulated by an insulator 12. The vacuum trigger gap 5 and the external conductor 4 are insulated by an insulator 13, to which an external lead terminal 9a is fixed. The vacuum trigger gap 5 is provided with a current collector 15 at its lower part, and is configured to be detachable from a current collecting electrode 17 fixed to a terminal plate 16. An insulator 18 is provided on the terminal plate 16 to insulate the current collecting electrode 17 and the external conductor 4, and hundreds of coaxial cables 19 are connected in the circumferential direction to each conductor to connect the capacitor bank 1. , reducing the inductance of the connection. In the upper part of the vacuum trigger gap device 3, several hundred coaxial cables 19a are connected in the circumferential direction of an external lead-out terminal 9°9a fixed in the same way as in the lower part.
It is connected to a high voltage transmission board 21 and a low voltage transmission board 22 through a cable duct 20. High and low voltage transmission plates 21, 221!
I is insulated with an insulator 23. X-ray generation discharge tube 2
The inside is evacuated to a vacuum, and there are high and low voltage electrodes inside.
“is placed.

Note that in the figure, 26 is a protective resistor.

When the capacitor bank 1 is charged with the plasma X-ray source configured in this manner and the pulse source 27 is applied to the trigger electrode 8 and the external lead terminal 9a of the vacuum trigger gap 5, the A discharge occurs along the surface of the insulator 28, and plasma is generated between the opposing electrodes 6 and 7.

As a result, a discharge occurs between the opposing electrodes 6 and 7, and the high and low voltage electrodes 24 and 25 for generating X-rays are passed through the coaxial cable 19a.
is applied, and discharge occurs during this period. High and low voltage electrodes 24°2
When a desired X-ray generating material is used for 5, X-rays are generated between them, and the pattern of the mask 30 in the exposure device IO is irradiated onto the silicon wafer 31 through the X-ray extraction window 29, thereby exposing the silicon wafer 31.

In plasma X-ray sources, special consideration is given to reducing the inductance of the discharge circuit in order to improve the X-ray brightness. In particular, reducing the inductance of the vacuum trigger gap device 3 is an important issue. In this embodiment, the vacuum trigger gap device 3
In addition to using a coaxial structure to reduce inductance,
Since only the vacuum trigger gap 5 is configured to be able to be heated and degassed, and is also detachable, maintenance management including replacement work due to lifespan is facilitated.

In this way, according to this embodiment, the vacuum trigger gap device 3
Since they are configured coaxially, the inductance of the vacuum trigger gear assembly [3] can be reduced. Therefore, the brightness of X-rays generated can be improved.

It is economically advantageous because materials that can be used at room temperature can be used for the parts other than the vacuum trigger gap 5, and since only the vacuum trigger gap 5 can be attached and detached, maintenance management is easy and the replacement work at the end of life can be significantly shortened. .

Another embodiment of the invention is shown in FIG.

In this embodiment, the diameters of the opposing electrodes 6a and 7a are increased,
In addition to reducing the distance between the vacuum trigger gap device and the external conductor (see FIG. 1), the current circuit is regulated to lower the inductance of the vacuum trigger gap device than in the previous case.

In this case, the inner surface of the electrode 7a can be used as the current collector 15a, and the lengthwise distance can also be shortened, making it possible to lower the inductance. Further, since the vacuum sealing valve 32 can also be provided on the atmosphere side within the electrode 6a, it is possible to effectively utilize space.

FIG. 3 shows yet another embodiment of the invention. In this embodiment, the X-ray generating discharge tube 2a and the vacuum trigger gap device 3 are directly connected to reduce the inductance of the high and low voltage transmission plates and the coaxial cable (see FIG. 1). The X-ray generating discharge tube 2a shown in the figure is a plasma focus type discharge tube which is one type of plasma X-ray source, and is described in, for example, Japanese Patent Laid-Open No. 104548/1983. Vacuum trigger gap device! 3 external extraction terminal 9
, 9a are connected to the capacitor bank by coaxial cables as in FIG. 1 above. Plasma focus type discharge tube 2
After vacuum evacuation, the interior of a is filled with a normal X-ray generating gas (neon, krypton, argon, etc.), and the insulator 3 is inserted between the coaxial facing electrodes 6b and 7b by operating the trigger switch.
According to this embodiment, the arc between the electrodes 6b and 7b is magnetically driven and advances to the tips of the electrodes 6b and 7b, pinching the plasma and generating X-rays. Inductance such as a low voltage transmission plate can be omitted.

〔Effect of the invention〕

As described above, the present invention provides a plasma X-ray source that has a vacuum trigger gap device with low inductance and easy maintenance management. Obtainable.

[Brief explanation of drawings]

FIG. 1 is a partial vertical side view of an embodiment of the plasma X-ray source of the present invention, FIG. 2 is a vertical side view of a vacuum trigger gap of another embodiment of the plasma X-ray source of the present invention, and FIG. FIG. 3 is a longitudinal sectional side view of still another embodiment of the plasma X-ray source of the present invention. DESCRIPTION OF SYMBOLS 1... Capacitor bank, 2, 2a... Discharge tube for X-ray generation, 3... Vacuum trigger gap device, 4... External conductor, 5... Vacuum trigger gap, 6, 6a, 6b
... Electrode, 7, 7a, 7b ... Electrode, 8 ... Trigger electrode, 9.9a, ... External lead terminal, 15, 15a
...Electronic collector, 32...Vacuum sealing valve. 1&-11 Dentaku

Claims (1)

[Claims] 1. A vacuum trigger gap device forming a discharge circuit together with a capacitor bank and an X-ray generating discharge tube, the vacuum trigger gap device having an external conductor and a vacuum trigger gap, In a plasma X-ray source that has a pair of opposing electrodes provided in a vacuum vessel and a trigger electrode provided on at least one of the opposing electrodes, the gap is used to separate the outer conductor between the two. A plasma X-ray source characterized in that an external extraction terminal is provided at at least one end of the terminal, and is arranged coaxially with the vacuum trigger gap on the outer periphery of the vacuum trigger gap, and the vacuum trigger gap is formed to be detachable. . 2. The plasma X-ray source according to claim 1, wherein the vacuum trigger gap is provided with a current collector that can freely approach and separate at at least one end thereof. 3. The plasma X-ray source according to claim 1, wherein the vacuum trigger gap includes a vacuum sealing valve. 4. Claim 1, wherein the vacuum trigger gap device and the X-ray generating discharge tube are directly connected.
Plasma X-ray source as described in section.