JPH0545499A - X-ray generator - Google Patents

Abstract

PURPOSE:To make it possible to use an X-ray of large intensity by separating the X-ray on or near the optical axis of a laser light from the laser light. CONSTITUTION:A laser light 5 emitted from a light source is passed through a lens 6 and a window part 7 and led into a vacuum vessel 8, and after passing through an opening 1a of an X-ray reflector 1 with the opening, it is condensed on a target object 4. Out of the X-rays generated from plasma produced by condensation of light, the X-ray radiated in a solid angle in view of the reflector 1 on and near the optical axis of the laser light 5 is reflected by the X-ray reflector 1 and also made to be a parallel light and is applied as the parallel light 9 onto an X-ray optical element 11. According to this constitution, the X-ray on the optical axis of the laser light can be separated from the laser light and it becomes possible to use the ray of large intensity on the optical axis of the laser light.

Description

Detailed Description of the Invention

[0001]

The present invention relates to, for example, an X-ray microscope and an X-ray microscope.
It is used for a line exposure device and the like.

[0002]

2. Description of the Related Art An optical device such as an X-ray microscope utilizes X-rays generated from plasma generated by focusing laser light on a solid target. In such an X-ray generator, X
As for the spatial intensity distribution of the X-ray generated from the ray generation source, for example, when the laser light is vertically incident on the solid target, the X-ray intensity is highest on the laser optical axis. The X-ray intensity decreases as the angle from the laser optical axis increases.

Conventionally, in the above optical device, an object to be illuminated, X
X-rays having a large angle from the laser optical axis have been used so that the linear optical elements and their holding devices do not block a part of the laser light.

[0004]

However, in the conventional optical device as described above, the intensity of the X-ray used is insufficient because the X-ray used is in the direction of a large angle from the laser optical axis. In addition, X obtained by increasing the output of the laser light
Although the strength of the wire increases, in this case, there is a problem that the device becomes large. Further, the generated X-rays have no directivity and radiate in all directions of the solid target, so that wasted X-rays increase and the efficiency is poor.

An object of the present invention is to solve the above-mentioned problems and to obtain an X-ray generator which can use one having a high X-ray intensity.

[0006]

In order to achieve the above object, in the X-ray generator according to claim 1, X-rays are generated from plasma generated by focusing laser light on a solid target. The generator includes a separating means for separating X-rays on or near the optical axis of the laser light from the laser light.

According to a second aspect of the present invention, there is provided an X-ray generator according to the first aspect, wherein the separating means has a high transmittance for laser light or laser light. The X-ray reflection mirror has an opening that allows light to pass therethrough.

According to a third aspect of the present invention, there is provided an X-ray generator according to the first aspect, wherein the separating means has a high reflectance with respect to a laser beam and emits X-rays. On the other hand, it is a member having a high transmittance.

[0009]

In the present invention, since means for separating X-rays on the laser optical axis from the laser light is provided, for example, when X-rays are generated by vertically injecting laser light into a solid target. The X-ray having the highest intensity on the laser optical axis can be separated from the laser light and used. Therefore, the X-ray intensity on the irradiated object can be increased.

Further, since the X-ray mirror is used as the separating means, depending on its shape and configuration, the X-ray is condensed to increase the X-ray intensity, the X-ray is monochromatic, or the absorption edge of the mirror constituent element is changed. It is possible to select a specific wavelength region of X-rays by utilizing the above. Further, the mirror can prevent ions or neutral particles scattered from the plasma from reaching the irradiated object or the X-ray optical element.

[0011]

EXAMPLES Examples of the present invention will be described below. Figure 1
FIG. 1 is a diagram showing an X-ray generator as a first embodiment of the present invention. The structure of the X-ray generator according to the present embodiment has a lens 6 that condenses the laser light 5 emitted from a light source (not shown).
And an X-ray reflection mirror 1 having an opening 1a in the vacuum container 8 and a target object 4 for generating plasma by laser irradiation. The X-ray optical element 11 is arranged.
The X-ray reflection mirror 1 is formed in a paraboloid of revolution,
It is set so that incident X-rays are reflected by parallel light.

In the above structure, the laser light 5 emitted from the light source passes through the lens 6, passes through the window 7 and is guided into the vacuum container 8, and after passing through the opening 1a of the reflection mirror 1. The light is focused on the target object 4. Of the X-rays generated from the plasma generated by the condensing, the X-rays emitted within the solid angle of the mirror 1 on and near the optical axis of the laser light 5 are reflected by the X-ray reflection mirror 1. The parallel light is converted into parallel light, and the parallel light 9 is irradiated onto the X-ray optical element 11.

If a multi-layer film mirror is used as the X-ray reflection mirror, it is possible to make the X-ray monochromatic. The shape of the multilayer mirror is not limited to a paraboloid, and may be a flat surface, a concave surface, a hyperboloid of revolution, a part of a spheroid, or the like. Further, it is not limited to the multilayer film mirror, and an oblique incidence mirror or the like may be used. As described above, various materials are widely used as long as they can reflect X-rays.

A second embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of providing the opening 1a in the X-ray reflecting mirror as in the first embodiment, the X-ray reflecting mirror 2 is made of a material having a high transmittance for the laser light 5. There is. Others are the same as those in the first embodiment.

In FIG. 2, the laser light 5 emitted from the light source passes through the lens 6 and the window portion 7, and passes through the vacuum vessel 8.
To the target object 4 after passing through the X-ray reflecting mirror 2. Of the X-rays generated from the plasma generated by the condensing, the X-rays emitted within the solid angle that looks into the mirror 2 on and near the optical axis of the laser light 5 are X-rays.
The X-ray optical element 11 is irradiated with parallel light 9 after being reflected by the line reflection mirror 2 and converted into parallel light.

The shape of the X-ray reflection mirror 2 is not limited to the paraboloidal shape as in the case of the first embodiment, and the configuration of the mirror is not limited to the multi-layered film mirror, and the laser light transmission and the X-ray transmission are possible. Those capable of line reflection are widely used.

A third embodiment of the present invention is shown in FIG. In this embodiment, as a means for separating X-rays on and near the optical axis of the laser from the laser light, a mirror 3 having a high reflectance for the laser light and transmitting the X-ray is used. Is.

The laser light 5 emitted from the light source receives the window 7
Is guided to the inside of the vacuum container 8, is reflected by the mirror 3, and is condensed on the target object 4. Of the X-rays generated from the plasma generated as a result, the X-rays radiated within the solid angle on the laser optical axis and in the direction close to the laser optical axis, looking into the mirror
Line 10 passes through mirror 3 and is illuminated by an object (not shown)
Alternatively, the X-ray optical element 11 is irradiated.

The mirror 3 is widely used as one that can reflect laser light and allow X-rays to pass through. Since the X-rays 10 that pass through the mirror 3 are in the wavelength region sandwiched by the absorption edges of the elements that make up the mirror 3, it is possible to select the wavelength of the X-rays depending on the constituent elements used.

When hard X-rays are used, the metal can be selected from a wide range by forming the mirror with a metal film. The shape of the mirror 3 is not limited to a paraboloid, and may be arbitrary, and a condenser lens may be provided separately from the mirror to condense the laser light 5. In the above embodiments, the incident angle of the laser light 5 on the target object 4 is arbitrary.

[0021]

As described above, the present invention is provided with a means for separating X-rays on the laser optical axis from the laser light. When a line is generated, the X-ray having the highest intensity on the laser optical axis can be used. Therefore, the X-ray intensity on the irradiated object can be increased.

Further, since the X-ray mirror is used as the separating means, depending on its shape and configuration, the X-ray may be condensed to increase the X-ray intensity, the X-ray may be monochromatic, or the absorption edge of the mirror constituent element may be changed. It is possible to use only X-rays in a specific wavelength region by utilizing the above. Furthermore, the mirror allows ions and neutral particles scattered from the plasma to be irradiated on the object,
Alternatively, there is an effect that it is possible to prevent it from reaching another X-ray optical element.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an X-ray generator according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an X-ray generator according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of an X-ray generator according to an embodiment of the present invention.

[Explanation of symbols]

 1: X-ray reflection mirror with aperture 2: Laser light transmission X-ray reflection mirror 3: Laser light reflection X-ray transmission mirror 4: Target object 5: Laser light 6: Lens 7: Window 8: Vacuum container 9: Reflected from mirror X-rays 10: X-rays transmitted through a mirror 11: X-ray optical element

Claims (3)

[Claims] 1. An X-ray generator for generating X-rays from plasma generated by concentrating laser light on a solid target,
X comprising a separating means for separating X-rays on or near the optical axis of the laser light from the laser light.
Line generator. 2. The X-ray reflection mirror according to claim 1, wherein the separating means is an X-ray reflection mirror having a high transmittance for laser light or having an opening through which the laser light passes. Line generator. 3. The X-ray generator according to claim 1, wherein the separating means is a member having a high reflectance for laser light and a high transmittance for X-rays. apparatus.