JP2000002673A - X-ray diffraction apparatus and diffraction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray diffraction apparatus in which an X-ray diffraction of a thin film formed on a cylindrical basic body, including an electrophotographic photosensitive body, can be measured with sufficient intensity. SOLUTION: An X-ray luminous flux diverged from a point light source G is reflected on an X-ray condenser mirror 3 on the irradiating side such that each point of a thin film 7 formed on a cylindrical basic body 5 is irradiated at a constant irradiation angle with respect to the tangential direction thereof. The X-ray condenser mirror 3 on the irradiating side is produced by curing a silicon wafer of about 100 μm and only such a luminous flux, out of diffracted X-rays reflected on the thin film 7, as having a constant scattering angle with respect to the tangential direction at each point is condensed at one point through an X-ray condenser mirror 9 on the detecting side. A slit 11 is set at the focal point of the mirror 9 and only the luminous flux passed through the slit 9 impinges on a detector 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an X-ray diffraction apparatus and method for evaluating the structure of a film formed on a curved surface such as an electrophotographic photosensitive member.

[0002]

2. Description of the Related Art An X-ray diffraction apparatus for measuring X-ray diffraction of a thin film formed on a flat surface has been known. FIG. 6 is a diagram showing Bragg reflection of a thin film by X-rays in a conventional X-ray diffractometer. X-rays applied to an arbitrary region of the thin film b formed on the plane a are reflected at the same angle.

In recent years, there has been an increasing need to measure X-ray diffraction of thin films formed on a cylindrical substrate such as an electrophotographic photosensitive member. However, in a conventional X-ray diffractometer,
It can be applied only to a plane, and cannot be applied to anything other than a plane such as a cylinder. FIG. 7 is a diagram showing X-ray Bragg reflection of a thin film formed on a cylindrical substrate. X-rays reflected from the thin film d formed on the substrate c are reflected in different directions depending on the irradiated area even at the same scattering angle. Could not. For this reason, conventionally, X-ray diffraction has been measured on a minute region that can be regarded as a plane approximately by using a thin X-ray beam.

[0004]

However, a thin X
Conventional X-ray diffractometers that measure X-ray diffraction in a very small area that can be regarded as an approximately flat surface using a line beam are not enough for thin films and thick films used in today's devices. High strength was not obtained. Since a thin film or a thick film having a sufficient area is formed on the substrate, the irradiation angle and the detection angle at each point of the irradiated area can be simultaneously controlled so that they are equal over the entire irradiation area. Then, it becomes possible to measure X-ray diffraction from a large area irradiation area,
Sufficient strength should be obtained.

Accordingly, the present invention has been made in view of such a point, and measures the X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member with sufficient intensity. It is an object of the present invention to provide an X-ray diffraction apparatus and a method capable of performing the same.

[0006]

In order to achieve the above object, an X-ray diffractometer according to claim 1 of the present invention comprises a film X-ray diffractometer.
An X-ray diffractometer for measuring X-ray diffraction is provided with an irradiation optical system for irradiating a film formed on a curved surface with an X-ray beam divergent from a point light source at an incident angle close to a tangential direction. Thereby, irradiation suitable for measuring X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member with sufficient intensity can be performed.

According to a second aspect of the present invention, there is provided an X-ray diffraction apparatus according to the first aspect, wherein the film is formed on a cylindrical surface, and the incident angle is set at each point on the cylindrical surface. Irradiation is made to be equal.

[0008] In the X-ray diffractometer according to claim 2,
The point light source may be placed on a straight line perpendicular to the axis of the cylinder.

Further, in the X-ray diffraction apparatus according to the second aspect, the point light source can be placed on the axis of the cylinder.

To achieve the above object, an X-ray diffractometer according to claim 3 of the present invention is characterized in that, in claim 1, the irradiation optical system has a condenser mirror having a curved spectral film. And

Further, in the first aspect, the irradiation optical system may be an optical system having a condenser mirror made of a spectral film curved so as to form a part of a spheroid.

To achieve the above object, an X-ray diffractometer according to claim 4 of the present invention is an X-ray diffractometer for measuring X-ray diffraction of a film. A detection optical system is provided which focuses diffracted X-ray luminous flux emitted at a predetermined scattering angle with respect to a tangential direction at each point from a point to one point. Accordingly, detection suitable for measuring X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member with sufficient intensity can be performed. Here, the predetermined scattering angle is a Bragg reflection angle within an angle range to be measured for X-ray diffraction.

In order to achieve the above object, an X-ray diffractometer according to a fifth aspect of the present invention is characterized in that, in the fourth aspect, the detection optical system has a condenser mirror having a curved spectral film. And

Further, in the X-ray diffractometer according to claim 4, the detection optical system is an optical system having a condenser mirror made of a silicon wafer curved so as to form a part of a spheroid. be able to.

Further, in the X-ray diffractometer according to claim 5, when measuring the diffracted X-ray luminous flux by changing the scattering angle, the surface shape and position of the converging mirror are adjusted in accordance with the scattering angle. Can be changed.

Further, in the X-ray diffraction apparatus according to claim 4, the detection optical system has a slit disposed at a position where the diffracted X-ray light beam is condensed, and the diffraction X-ray passing through the slit.
It is possible to adopt a configuration in which a detector for detecting a linear light beam is provided.

In order to achieve the above object, an X-ray diffractometer according to claim 6 of the present invention is an X-ray diffractometer for measuring X-ray diffraction of a film, comprising: An irradiation optical system that irradiates the film formed on the surface of the cylinder at an incident angle close to the tangential direction with respect to the film formed on the surface of the cylinder, and irradiates the incident angle at each point on the surface of the cylinder so as to be equal. From each point on the surface, diffracted X-ray luminous flux emitted at a predetermined scattering angle with respect to the tangential direction at each point is converged to one point, and the diffracted X-rays passing through a slit placed at the condensing position A detection optical system for detecting a linear light beam. Accordingly, X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member can be measured with a sufficient intensity.

The X-ray diffractometer of the present invention is an X-ray diffractometer for measuring the X-ray diffraction of a film.
A linear light beam is irradiated at an incident angle close to the tangential direction to a film formed on the surface of the cylinder by the irradiation optical system, and the incident angle is made equal at each point on the surface of the cylinder to form the light on the surface of the cylinder. From each point on the surface of the formed film, the diffracted X-ray luminous flux emitted at a predetermined scattering angle with respect to the tangential direction at each point is condensed to one point by the detection optical system, and is placed at the condensing position. A configuration may be adopted in which the diffracted X-ray beam passing through the slit is detected.

In the present invention, as the spectral film, a film composed of a crystal having high curvature and high perfection is most desirable, but when a measurement of a sharp diffraction pattern is not necessary (in many cases, it is not necessary in a thin film measurement). 3.) A film consisting of imperfect crystals with a low diffraction intensity, although having a lower resolution, is advantageous. For example, a material having a periodicity in the direction perpendicular to the surface (one-dimensional crystal) may be sufficient as long as it can be bent. 1) As those without crystal defects (close to perfect crystals),
There are silicon, Ge, InP, and the like. These wafers cause sharp Bragg reflection and can be slightly curved, but silicon has the highest bending strength and the highest integrity. 2) A plate-like graphite microcrystal deposited (pyrolytic graphite) has a one-dimensional period in the deposition direction (one-dimensional crystal) and is known as a spectral crystal. 3) An artificial lattice thin film in which layers of heavy elements (eg, Pt, Mo, etc.) and layers of light elements (eg, Si, C, etc.) are alternately and periodically deposited is also known as an X-ray mirror. Although the resolution is reduced, the materials of the above-mentioned classifications 2) and 3) among the imperfect crystals which can obtain the diffraction intensity are advantageous because they may be able to bend freely considerably. Metallic films could also be used for this purpose.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the X-ray diffraction apparatus and method according to the present invention will be described. [First Embodiment] FIG. 1 is a view showing a schematic configuration of an irradiation optical system of an X-ray diffraction apparatus according to a first embodiment. When the X-ray luminous flux emitted from the point light source G is reflected by the irradiation side X-ray focusing mirror 3, the X-ray luminous flux falls on a thin film (sample surface, organic photoconductor) 7 formed on the cylindrical base 5. At this time, irradiation is performed so that any point on the thin film 7 has a constant incident angle with respect to its tangential direction. For example, the incident angles at point a and point b in the figure are equal. FIG. 1 shows a case where the thin film 7 is irradiated at a slightly tangential incident angle (0 to 1 degree with respect to the tangent) at each point on the thin film 7 so as to be most suitable for the X-ray diffraction measurement of the thin film. .

The irradiation side X-ray focusing mirror 3 has a thickness of 100 μm.
It is manufactured by bending a silicon wafer of about m.
A technique for condensing an X-ray beam using a curved silicon wafer is already known. Since silicon wafers are non-transitional crystals, they have high breaking strength and can withstand significant shape changes. As a specific example, the base 5, the point light source G, and the irradiation side X-ray focusing mirror 3 when the wavelength of X-rays is λ = 1.5405 ° and the Bragg reflection angle of the (111) plane of silicon is 28.4 ° 1 is shown in FIG.

FIG. 2 is a diagram showing a schematic configuration of a detection optical system of the X-ray diffraction apparatus. The detection optical system includes a cylindrical substrate 5.
Of the diffracted X-rays reflected by the thin film 7 formed on
A detection-side X-ray focusing mirror 9 is provided which focuses only one having a predetermined scattering angle で at each point, that is, only a light beam whose emission angle is constant with respect to a tangent line at each point.
A slit 11 is provided at the focal position of the detection-side X-ray focusing mirror 9, and only a light beam passing through the slit 11 is incident on the detector 12.

As described above, the X-ray focusing mirror 9 on the detection side can collect the diffracted X-rays from the thin film 7 formed on the surface of the base 5, and the diffraction detected by the detector 13 by the slit 11. X-ray background can be removed. As a specific example, the wavelength of the X-ray is λ = 1.5405 °.
And the Bragg reflection angle of the (111) plane of silicon is 2
When the angle is 8.4 °, the positional relationship among the base 5, the detection-side X-ray focusing mirror 9, the slit 11, and the detector 12 at the scattering angle Θ = 20 ° is shown in FIG. Here, in order to measure the intensity of the diffracted X-ray as a function of the scattering angle Θ,
It is necessary to change the surface shape and position of the detection-side X-ray focusing mirror 9 for each scattering angle い to be detected.

FIG. 3 is a diagram showing the relationship between the angle ω of a point on the cylindrical surface, the scattering angle の on the cylindrical surface, and the Bragg reflection angle Φ at the detection-side X-ray focusing mirror 9. The X-ray luminous flux reflected from each point on the cylindrical surface in a tangential direction at that point, that is, in a direction forming a scattering angle に 対 し て with respect to the direction of the irradiated X-rays at that point is converted into a point T at which the slit 11 is placed. Detection side X for focusing on
When the shape of the line focusing mirror 9 is obtained, the coordinates (x, y) of the curved surface of the detection-side X-ray focusing mirror 9 are represented by [Equation 1] when the angle ω of the cylindrical surface is used as a parameter.

[0025]

(Equation 1)

For example, the wavelength of 1.5405 shown in FIG.
When the X-ray of Å is used, since the Bragg reflection angle of the silicon mirror whose crystal plane is (111) is Φ = 28.4, the surface shape and position of the silicon mirror are calculated according to the scattering angle Θ to be measured. By performing the control to change according to (1), it becomes possible to measure the X-ray diffraction of the curved surface.

[Second Embodiment] In the first embodiment, the case where the X-ray luminous flux radiated from the point light source G placed on the straight line perpendicular to the axis of the cylindrical body is shown, In the second embodiment, a case is shown in which an X-ray beam emitted from a point light source placed on the axis of a cylindrical body is irradiated.

FIG. 4 is a diagram showing a schematic configuration of an irradiation optical system of the X-ray diffraction apparatus according to the second embodiment. The first
Similarly to the embodiment, the irradiation-side X-ray focusing mirror 23 is manufactured by bending a silicon wafer having a thickness of about 100 μm. Since silicon wafers are non-transitional crystals, they have high breaking strength and can withstand significant shape changes. In the present embodiment, the irradiation side X-ray focusing mirror is formed by bending the silicon wafer so as to constitute a part of the spheroid.

As a specific example, the wavelength of X-rays is λ = 1.54.
05 °, the substrate 25 and the point light source G when the Bragg reflection angle of the (111) plane of silicon is 28.4 °.
FIG. 4 shows the positional relationship of the irradiation side X-ray focusing mirror 3. The X-ray luminous flux diverging from the point light source G placed at the first focal position of the spheroid is reflected inside the irradiation side X-ray focusing mirror 23 curved so as to form a part of the spheroid. The thin film 27 formed on the base 25 at a slight incident angle (0 to 1 degree with respect to the tangent) on the circumferential surface of the base 25 to be measured when moving in the direction converging to the second focal position.
Is irradiated. At this time, the X-ray luminous flux enters the same circumferential surface of the base 25 at the same incident angle.

FIG. 5 is a diagram showing a schematic configuration of a detection optical system of the X-ray diffraction apparatus. Like the irradiation-side X-ray focusing mirror 23, the detection-side X-ray focusing mirror 33 is manufactured by bending a silicon wafer having a thickness of about 100 μm so as to form a part of a spheroid. When the X-ray flux diverging from the same circumferential surface of the base 25 on a straight line passing through the first focal position of the spheroid is reflected by the detection-side X-ray focusing mirror 33,
The light is guided to be condensed at the second focal position, and is detected by the detector 22 through the slit 31 placed at the second focal position.

As described above, of the diffracted X-rays reflected by the thin film formed on the cylinder, those having a predetermined scattering angle at each point, that is, a light beam having an incident angle at each point and a constant scattering angle Is focused on a single point by the detection-side X-ray focusing mirror 33, and the detector 22 detects only the X-ray luminous flux passing through the slit 31 placed at the second focal position,
The diffracted X-rays from the thin film 27 can be collected, and the background of the diffracted X-rays detected by the detector 22 can be removed.

As a specific example, the wavelength of the X-ray is λ = 1.54.
FIG. 5 shows the positional relationship between the base 25, the detection-side X-ray focusing mirror 33, the slit 31, and the detector 22 when the Bragg reflection angle of the silicon (111) plane is 28.4 °. I have. In order to measure the diffraction X-ray intensity as a function of the scattering angle Θ, it is necessary to change the surface shape and position of the detection-side X-ray focusing mirror 33 for each scattering angle い to be detected.

From each point on the cylindrical surface to the tangential direction at that point,
That is, the detection side X-ray converging mirror 33 for condensing the X-ray luminous flux scattered in the direction formed by the direction of the X-ray irradiated on the point and the scattering angle に at one point T where the slit 31 is placed. The method for obtaining the shape is the same as in the first embodiment. That is, the curved surface (x, y) of the detection-side X-ray focusing mirror 33 is
Assuming that the angle ω of the cylindrical surface is a parameter, the angle ω is represented by the above-described [Equation 1].

As described above, in the second embodiment in which the X-ray beam is emitted from the point light source placed on the axis of the cylinder,
As in the first embodiment, by performing control to change the surface shape and position of the silicon mirror according to the mathematical expression (1) in accordance with the scattering angle Θ to be measured, measurement of X-ray diffraction of a curved surface can be performed. Will be possible.

In the above embodiment, the case where a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member is measured has been described. However, the present invention is not limited to a columnar shape, but may be formed on an arbitrary curved surface. The present invention can be similarly applied to the measurement of a thin film. In addition, the present invention can be applied to measurement of X-ray diffraction of a thick film as well as a thin film.

[0036]

According to the X-ray diffractometer according to the first aspect of the present invention, in the X-ray diffractometer for measuring the X-ray diffraction of the film, the X-ray luminous flux diverging from the point light source is formed on a curved surface. Since the irradiation optical system for irradiating the film with an incident angle close to the tangential direction is provided, each point on the surface of the cylinder can be irradiated with the X-ray beam at the same incident angle. Therefore, irradiation suitable for measuring X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member with sufficient intensity can be performed.

According to the X-ray diffraction apparatus of the second aspect,
The film is formed on the surface of a cylinder, and the irradiation is performed so that the incident angle is equal at each point on the surface of the cylinder. Therefore, the irradiation can be performed at an incident angle suitable for thin film diffraction at each point on the surface of the cylinder.

According to the X-ray diffractometer according to the third aspect,
Since the irradiation optical system has a condensing mirror in which a silicon wafer is curved, the condensing mirror can be easily formed by using a silicon wafer which has a large breaking strength and is a non-transition crystal capable of withstanding a considerable shape change. It can be formed into a curved shape.

According to the X-ray diffraction apparatus of the fourth aspect,
In an X-ray diffraction apparatus for measuring X-ray diffraction of a film, a diffracted X-ray luminous flux emitted at a predetermined scattering angle with respect to a tangential direction at each point from each point on the surface of the film formed on a curved surface is converted into one point. Since the detection optical system for converging light is provided, only the diffracted X-ray luminous flux having the same scattering angle can be converged from each point on the surface of the cylinder. Therefore, detection suitable for measuring X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member with sufficient intensity can be performed.

According to the X-ray diffractometer of the fifth aspect,
Since the detection optical system has a condensing mirror in which a silicon wafer is curved, the condensing mirror can be easily formed by using a silicon wafer which has a large breaking strength and is a non-transition crystal capable of withstanding a considerable shape change. It can be formed into a curved shape.

According to the X-ray diffractometer of the sixth aspect,
In an X-ray diffraction apparatus for measuring X-ray diffraction of a film, an X-ray luminous flux diverging from a point light source is incident at an incident angle close to a tangent direction to a film formed on a surface of a cylinder, and at each point on the surface of the cylinder. An irradiation optical system that irradiates the light so that the incident angles are equal;
From each point on the surface of the film formed on the cylindrical surface, the diffracted X-ray luminous flux emitted at a predetermined scattering angle with respect to the tangential direction at each point is condensed into one point and placed at the condensing position. And a detection optical system for detecting the diffracted X-ray luminous flux passing through the slit formed, so that X-ray diffraction of a thin film formed on a cylindrical substrate such as an electrophotographic photosensitive member has a sufficient intensity. Can be measured.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of an irradiation optical system of an X-ray diffraction apparatus according to a first embodiment.

FIG. 2 is a diagram illustrating a schematic configuration of a detection optical system of the X-ray diffraction apparatus.

FIG. 3 shows an angle ω of a point on a cylindrical surface and a scattering angle Θ on a cylindrical surface.
FIG. 4 is a diagram illustrating a relationship between a Bragg reflection angle Φ at a detection-side X-ray focusing mirror 9 and a detection side X-ray focusing mirror 9.

FIG. 4 is a diagram illustrating a schematic configuration of an irradiation optical system of an X-ray diffraction apparatus according to a second embodiment.

FIG. 5 is a diagram showing a schematic configuration of a detection optical system of the X-ray diffraction apparatus.

FIG. 6 is a diagram illustrating Bragg reflection of a thin film by X-rays in a conventional X-ray diffraction apparatus.

FIG. 7 is a diagram showing X-ray Bragg reflection of a thin film formed on a cylindrical substrate.

[Explanation of symbols]

 3, 23 Irradiation side X-ray focusing mirror 5, 25 Substrate 7, 27 Thin film 9, 33 Detection side X-ray focusing mirror 11, 31 Slit 12, 22 Detector

Claims (6)

[Claims] 1. An X-ray diffractometer for measuring X-ray diffraction of a film, comprising: an irradiation optical system for irradiating a film formed on a curved surface with an X-ray beam divergent from a point light source at an incident angle close to a tangential direction. An X-ray diffraction apparatus comprising: 2. The X-ray diffraction apparatus according to claim 1, wherein the film is formed on a surface of a cylinder, and the irradiation is performed such that the incident angles are equal at each point on the surface of the cylinder. 3. The X-ray diffraction apparatus according to claim 1, wherein the irradiation optical system has a condensing mirror having a curved spectral film. 4. An X-ray diffractometer for measuring X-ray diffraction of a film, comprising: diffracting light from each point on the surface of the film formed on a curved surface at a predetermined scattering angle with respect to a tangential direction at each point. X having a detection optical system for converging an X-ray beam at one point.
Line diffractometer. 5. The X-ray diffraction apparatus according to claim 4, wherein said detection optical system has a condenser mirror having a curved spectral film. 6. An X-ray diffractometer for measuring X-ray diffraction of a film, wherein an X-ray beam diverging from a point light source is incident on the film formed on the surface of the cylinder at an incident angle close to a tangential direction with respect to the film. An irradiation optical system that irradiates the light so that the incident angles are equal at each point on the surface, and from each point on the surface of the film formed on the cylindrical surface, at a predetermined scattering angle with respect to a tangential direction at each point. An X-ray diffractometer comprising: a detection optical system that converges the diffracted X-ray luminous flux to be emitted to one point and detects the diffracted X-ray luminous flux passing through a slit placed at the condensing position. .