JP2019078593A - Crystal array detector, small angle scattering measurement device and small angle scattering measurement device - Google Patents

Abstract

To enable measurement and analysis of a structure over a wide range of sizes.SOLUTION: A crystal array detector includes: a vacuum chamber; a plurality of analyzer crystals which are arranged along an optical axis in the vacuum chamber and each of which is held at a different angle with respect to the optical axis; and a detector for detecting radiation scattered by each of the analyzer crystals. Each of the analyzer crystals selects the specific length and a scattering angle from among scatter radiation scattered by an external sample and incident on the vacuum chamber and then scatters.SELECTED DRAWING: Figure 6

Description

  The present invention relates to small angle scatter measurements, and in particular to ultra small angle scatter measurements using crystal array detectors.

  Radiation such as X-rays, electron beams and neutrons is used for nondestructive inspection of substances. While X-rays are scattered by electrons of atoms, neutrons without charge are scattered by nuclei. Small-angle X-ray scattering has higher sensitivity for atoms with larger atomic numbers, but the scattering ability of light elements (such as hydrogen) to neutrons is approximately the same order of magnitude as elements with larger atomic numbers.

  Measurement and analysis using neutron scattering are effective for analysis of light-weight elements such as hydrogen atoms, and are applied to diagnosis of diseases caused by morphological changes of proteins (biopolymers). On the other hand, small-angle neutron scattering measurement can be used to specify the structure or spatial distribution of a polymer larger than a biomolecule. A method has been proposed to efficiently identify the shape and arrangement of the filler of the rubber material by optimizing the range of the absolute value of the scattering vector (or the wave number, hereinafter referred to as "q") and obtaining the scattering data. (See, for example, Patent Document 1).

JP, 2013-108800, A

  In general, small angle scattering measurement of neutrons is used to analyze the internal structure of several nano to several hundreds of nano meter. For the analysis of substances in the micron range, optical measurement using electron beams or laser light with a long wavelength is usually applied. However, depending on the type of object to be measured and the configuration of the optical system, an electron beam with a small transmission power or a long wavelength laser beam can not pass through the sample.

  The spatial period of the structure and the magnitude of the scattering vector are in inverse proportion to each other. As the scattering vector q is larger, analysis of a finer structure is possible. Conversely, if the scattering vector q (absolute value) can be expanded in the direction of decreasing it, the probe of the conventional small angle scattering measurement device can be used as it is to analyze a larger spatial structure. This applies not only to small angle scattering measurement of neutrons, but also to small angle scattering measurement using electromagnetic radiation such as X-rays.

  An object of the present invention is to provide an ultra-small angle scattering measurement device which enables measurement and analysis of a structure over a wide range of sizes.

  In order to solve the above problem, the scattering at very small angles is detected, and the lower limit (minimum value) of the scattering vector q is expanded in a smaller direction. Specifically, analysis of a structure with a wide range of sizes is realized by accurately detecting radiation scattered at an ultra-small angle using a detector using a crystal array.

In a first aspect of the invention, a crystal array detector is
A vacuum chamber,
A plurality of analyzer crystals disposed along the optical axis in the vacuum chamber and each held at a different angle to the optical axis;
A detector for detecting the radiation scattered by each of the analyzer crystals;
Have
Each of the analyzer crystals scatters by selecting a specific wavelength and a scattering angle from scattered radiation scattered by an external sample and incident on the vacuum chamber.

  This configuration enables analysis of a large structure in a region where the scattering vector q is small.

In a second aspect of the invention, a small angle scatterometer using a crystal array detector is:
An apparatus body comprising a sample holder for holding a sample, and a small angle scatter detector for detecting scattered radiation scattered by the sample;
A crystal array detector disposed downstream of the device body;
Have
The small angle scatter detector has an aperture on the optical axis of incident radiation incident on the device body,
The crystal array detector detects ultra-small-angle scattered radiation that has passed through the opening and has entered the crystal array detector among the scattered radiation.

  This configuration can expand the range of measurable object sizes.

  The above configuration enables measurement and analysis of substances over a wide range of sizes.

It is an upper surface schematic diagram of the small angle scattering measurement device of an embodiment. FIG. 2 is a schematic perspective view of an apparatus main body. It is a schematic diagram of a small angle scattering detector. It is a conceptual diagram explaining a time-of-flight method. It is a conceptual diagram explaining a time-of-flight method. It is a schematic top view of the crystal array detector of an embodiment. It is a figure explaining the principle of ultra-small angle scattering detection by a crystal array detector. It is a figure which shows the neutron count number by a crystal | crystallization array detector. It is a figure which shows the measurement result in a small angle scattering detector. It is a figure which shows the expansion of the analysis range (scattering vector range) by having arrange | positioned the crystal array detector.

  FIG. 1 is a schematic view of the configuration of the small-angle scattering measurement device 1 according to the embodiment as viewed from the top. The small-angle scattering measurement apparatus 1 may be a small-angle scattering measurement apparatus using particle radiation such as neutrons, or may be a small-angle scattering measurement apparatus using high-intensity electromagnetic radiation such as X-rays. In the following example, small-angle neutron scattering is taken as an example.

  The small angle scattering measurement device 1 has a device body 10 and a crystal array detector 20 disposed behind the device body 10 as viewed from the neutron beam incident side. A collimator 5 that narrows the incident neutron flux in parallel may be disposed on the incident side of the apparatus main body 10.

  The device body 10 includes, as an example, a backscattering detection bank 13 for detecting backscattering, a 90 ° detection bank 14 for detecting scattering in an in-plane direction orthogonal to the optical axis, a low angle detection bank 15 for detecting forward scattering, It has a small angle scattering detector 11 which detects small angle scattering. The sample holder 12 is disposed inside the sample scattering tank 19 of the 90 ° detection bank 14 and holds the sample 30.

  As a feature of the embodiment, the small angle scattering detector 11 having the opening 111 is disposed at the rear end face of the device body 10, and the crystal array detector 20 is disposed further to the rear of the small angle scattering detector 11. The crystal array detector 20 is connected to the opening 111 of the small angle scattering detector 11 while maintaining a vacuum state.

  The aperture 111 is formed at the center of the small angle scattering detector 11 so that the center of the aperture substantially coincides with the optical axis, and passes ultra-small angle scattered neutrons not detected by the small angle scattering detector 11. The small angle scattering detector 11 detects small angle scattering in a region other than the aperture 111. Small-angle scattering generally means scattering with a scattering angle (2θ) of 5 ° to 6 ° or less. The opening 111 is provided at a position corresponding to the dead zone of the small angle scattering detector 11, and its diameter is, for example, 100 mm.

  Passing through the aperture 111 of the small angle scattering detector 11 is neutron scattered from the sample 30 at a very small scattering angle or neutron beam transmitted through the sample 30 without scattering (or diffraction). Here, scattering at a very small angle in the 2θ direction is referred to as “ultra-small-angle scattering” for convenience.

  By arranging the crystal array detector 20 behind the device body 10, the ultra-small angle scattered neutrons not detected by the small angle scattering detector 11 are detected, and the range of data points of the small angle scattering measurement is extended to the ultra small angle region Do. The direction of extension of the measurement range is the direction in which the lower limit of the magnitude of the scattering vector q extends, and is the direction in which the spatial period d that can be analyzed is increased. Specific configurations and detection principles of the small angle scattering detector 11 and the crystal array detector 20 at the subsequent stage will be described later.

  In the measurement operation, the neutron flux output from the neutron generation target 2 is guided by the neutron conduit 3 in the direction of the small angle scattering measurement device 1, collimated by the collimator 5, and is incident on the device main body 10. As a neutron source, any neutron source can be used, such as one using radioactive isotopes, one using a nuclear reactor, and one using an accelerator. Here, as an example, protons accelerated by a synchrotron collide with a neutron generation target 2 of mercury (Hg) to generate neutrons by a spallation reaction.

  The collimator 5 is, for example, a multilayer collimator in which layers impervious to neutrons (for example, gadolinium oxide coated on a silicon wafer) and permeable layers (for example, a silicon wafer or an air layer) are alternately arranged. Shape the shape to produce parallel beams. As an example, a multi-layered collimator having a desired opening can be formed by combining opaque materials such as prisms, cylinders, etc. along the beam axis in a well-gage type, a hexagonal type, or the like.

  The collimated neutron flux is incident on the sample 30 held by the sample holder 12 in the apparatus main body 10. The sample 30 is held such that the angle θ of the incident neutron beam with respect to the sample surface is a very shallow angle. Incident neutrons are scattered in various directions at a scattering angle 2θ if they satisfy Bragg's diffraction conditions. In practice, diffraction in a direction determined by the arrangement of atoms is dominant, but detecting scattering in all directions improves detection accuracy. If the Bragg condition is not satisfied, the neutrons will not be scattered but will pass through the sample 30 as they are.

  The collimator 5 is aimed at the center of the opening 111 of the small angle scattering detector 11, and the small angle scattering measurement is performed so that the scattered neutrons scattered at an extremely small angle are incident on the subsequent crystal array detector 20 through the opening 111. The device 1 is designed. The device body 10 detects total scattering including backscattering, orthogonal scattering, forward scattering, and small angle scattering. The ultra-small angle scattered neutrons that have passed through the dead zone of the device body 10 are detected by the crystal array detector 20 at the subsequent stage. The neutrons transmitted through the crystal array detector 20 as they are are absorbed by the beam damper 7.

  The device body 10 and the crystal array detector 20 are connected to the processor 50, and the detection result of the device body 10 and the detection result of the crystal array detector 20 are respectively supplied to the processor 50. The processor 50 analyzes the detection result and analyzes the internal structure, internal distribution, and the like of the sample 30.

  FIG. 2 is a schematic perspective view of the apparatus main body 10. The crystal array detector 20 is disposed behind the device body 10 as viewed from the radiation source. The backscattering detection bank 13 of the device body 10 has a backscattering detector 16 on the entrance side of the neutron flux. The 90 ° detection bank 14 has orthogonal scatter detectors 17 around it. The low angle detection bank 15 is located behind the 90 ° detection bank 14 and has a low angle scatter detector 18 along the side. The low angle scattering detector 18 detects neutrons scattered forward from the sample 30.

  The small angle scattering detector 11 detects neutrons scattered at small angles at the rear end face of the device body 10. Very small angle scattered neutrons not detected by the small angle scattering detector 11 enter the crystal array detector 20 rearward from the opening 111.

  The outputs of the backscattering detector 16, the orthogonal scattering detector 17, the low angle scattering detector 18 and the small angle scattering detector 11 are each connected to a processor 50. Processor 50 may analyze the data from backscatter detector 16, orthogonal scatter detector 17, low angle scatter detector 18, and small angle scatter detector 11 separately or collectively.

By detecting backscattering, orthogonal scattering, and forward scattering in each bank of the device body 10, a measurement range of a scattering vector q of 5 nm ⁻¹ (0.5 Å ⁻¹ ) or more is covered. As described below, by providing the small angle scattering detector 11, the scattering vector q covers the range of 7 × 10 ^-2 nm ^{-1 to} 5 nm ^-1 (0.007 Å ^{-1 to} 0.5 Å ^-1 ). can do. Furthermore, the crystal array detector 20 that detects ultra-small angle scattering can cover the range of q ≦ 7 × 10 ⁻² nm ⁻¹ . The smaller the scattering angle, the larger the spatial structure. Also, the longer the wavelength of incident neutrons, the larger the spatial structure can be measured.

The scattering vector q is
q = (4π / λ) sin θ (1)
Is represented by λ is the wavelength of neutrons, and θ is half the scattering angle. The scattering angle (2θ) is an angle formed by the transmission direction of the incident ray and the scattering direction. In the case of accelerated neutron flux, it is a white neutron and contains neutrons of various wavelengths.

Bragg's diffraction condition is
2d * sin θ = λ (2)
And represents the condition under which the structure of the spatial period d of the sample 30 contributes to scattering in the 2θ direction.

From equations (1) and (2),
q = 2π / d (3)
Led. As q increases, the spatial period d decreases, and a fine structure can be analyzed.

  By reducing the size of the scattering vector q, it is possible to analyze a structure having a larger space size, for example, a size on the order of microns. From equation (1), the scattering vector q becomes smaller as θ is smaller, that is, as 2θ is smaller.

  In the configuration of FIG. 1, small angle scattering is detected by the small angle scattering detector 11 at the rear end of the device main body 10, and ultra small angle scattering is detected by the crystal array detector 20 at the rear stage of the small angle scattering detector 11. This enables measurement and analysis in a wide q range using the same neutron probe in the same device.

  FIG. 3 is a schematic view of the small angle scattering detector 11. The small angle scattering detector 11 is formed by combining a large number of rod-like neutron detectors 112 in a multilayer. In the example of FIG. 3, the rod-like neutron detector 112 is assembled in three layers and exposes the opening 111 at the center. The first layer is formed of a neutron detector 112a whose major axis extends transverse to the vertical cross section of the device. The second layer is formed of a neutron detector 112b whose major axis extends in the longitudinal direction of the vertical cross section of the device. The third layer is formed of a neutron detector 112c whose major axis extends laterally in the vertical cross section of the device. By arranging the neutron detectors 112a to 112c without gaps except for the opening 111, neutrons scattered in small angles are efficiently detected.

Inside the neutron detector 112 is enclosed a gas that interacts (nuclear reaction) with neutrons. Here, a He detector in which ³ He gas is sealed is used, but not limited to this, a detector including lithium (Li) and boron (B) as a neutron detection substance may be used. An electrode passes through the center of the neutron detector 112, and a voltage is applied between the electrode and the inner wall of the vessel. ^{When 3} He gas is used, electrons ionized by charged particles (protons) generated by collision of neutrons and ³ He are attracted to the electrode by the electric field, and current flows.

  The output of the small angle scattering detector 11 is connected to the processor 50, and the scattering intensity is measured by the time of flight method. The wavelength λ (ie, energy) of the neutron is calculated from the time of flight of the neutron, ie, the time difference between the output time of the neutron and the detection time.

  The rod-like neutron detectors 112 are each assigned an identification number, and the detection position is specified. Further, from the power difference between both ends of the electrode of the neutron detector 112, the detection position in the one-dimensional direction in the neutron detector 112 is specified. The distance from the position of the sample 30 to the small angle scattering detector 11 is known in advance, and the scattering angle (2θ) is specified by the detection position. Knowing the wavelength λ and the angle θ, the scattering vector q can be calculated from equation (1) and the measured scattering intensity can be plotted as a function of the scattering vector q.

  4 and 5 are conceptual diagrams of neutron measurement by the time of flight method. The protons are accelerated from the ion source and collide with the neutron generation target 2 at, for example, 25 Hz (1/40 ms). Due to the collision, pulsed neutrons are output from the neutron generation target 2. The pulsed neutrons are pulses having a continuous energy distribution (velocity distribution) as shown in FIG.

  The distance from the radiation source (neutron generation target 2) to the sample 30 is L1, and the distance from the sample 30 to each neutron detector 112 of the small angle scattering detector 11 is L2. If the neutron generation timing and detection timing at the neutron generation target 2 are known, the flight time of the neutron can be known. The distances L1 and L2 are set in advance by design. From the time of flight and flight distance, we can know the velocity of the detected neutron, that is, the energy.

  Among the neutrons scattered by the sample 30, scattered neutrons scattered at an ultra-small angle pass through the opening 111 of the small-angle scattering detector 11, and are detected by the crystal array detector 20 according to the principle described later.

  Referring to FIG. 5, a pulsed neutron flux is output from the source at, for example, 25 Hz. The time of neutrons arriving at the neutron detector 112 differs depending on the energy (wavelength) of the neutrons contained in the neutron flux. The high energy (short wavelength) neutrons first arrive at the neutron detector 112, and the low energy (long wavelength) neutrons arrive at the neutron detector 112 later. In FIG. 5, the slope of the oblique line segment extending from the output pulse of the neutron to the detection position indicates the velocity of the neutron. By monitoring the pulse generation time and detection time, it is possible to know the energy of the detected neutron, that is, the wavelength.

  In FIG. 5, the measurement is performed in a single frame mode in which the detection time of neutrons is measured for each pulse, but when the width of the energy distribution of neutrons is large, the delay of detection time is larger than the pulse interval It can be. In that case, every other pulse neutron may be masked to operate in the double frame mode.

  FIG. 6 is a top view of the crystal array detector 20 of the embodiment. Neutrons that have passed through the opening 111 of the small angle scattering detector 11 enter the crystal array detector 20. The crystal array detector 20 has a vacuum chamber 25 in which a plurality of crystals are arranged along the optical axis. The crystal is, for example, a silicon crystal plate processed into a rectangle, a square or the like. In this example, ten silicon crystals 21-1 to 21-10 (hereinafter collectively referred to as "silicon crystals 21" as appropriate) are disposed along the optical axis. The size of the silicon crystal is, for example, 100 mm × 50 mm × 0.5 mm. Each of the silicon crystals 21-1 to 21-10 is held by a holder connected to a driving means such as a goniometer, and the angle thereof can be adjusted individually by the processor 50.

  On the inner side wall of the crystal array detector 20, a detector 22 is disposed in parallel with the array of silicon crystals 21-1 to 21-10. The incident planes of the silicon crystals 21-1 to 21-10 are inclined at different angles with respect to the optical axis. The neutrons scattered by each of the silicon crystals 21-1 to 21-10 are detected by the detector 22.

  The detector 22 is, for example, a rod-like He detector having an inner diameter of 12.5 mm and a sensing length of 600 mm. The sensing length of the detector 22 is longer than the arrangement length of the silicon crystals 21-1 to 21-10, and the detector 22 can specify the detection position of neutrons in a one-dimensional direction. The inner surface of the crystal array detector 20 is covered with a neutron absorbing material such as rubber except for the detector 22.

  Since neutrons have no charge, they have excellent permeability to substances. In a perfect crystal of silicon, neutrons transmit with almost 100% transmission. However, when neutrons pass through silicon, the state of the crystal plane (lattice plane spacing and incident angle θ of the neutron beam with respect to the lattice plane), and the wavelength λ of the neutron beam satisfy Bragg's diffraction condition (2d * sin θ = λ) In the case of filling, part of the neutron beam is diffracted (scattered) in the direction of 2θ.

  The neutrons incident on the silicon crystal 21 are neutrons scattered by the sample 30. The silicon crystal 21 functions as an analyzer that selects only neutrons of specific energy among neutrons scattered by the sample 30.

  The lattice spacing of the (111) plane of silicon corresponds to the space period d of Bragg's diffraction condition and is about 0.31 nm. The incident angle θ is determined by the angle of the incident surface of the silicon crystal 21 with respect to the optical axis. Among the ultrasmall-angle scattered neutrons incident on the crystal array detector 20, neutrons of a wavelength (energy) satisfying 2d * sin θ = λ are scattered by the silicon crystal 21 and detected by the detector 22. Neutrons that do not satisfy the Bragg's condition (off Bragg's condition) pass through the silicon crystal 21 as they are.

  By arranging a plurality of silicon crystals 21-1 to 21-10 in series at different angles along the optical axis to configure a crystal array, neutrons that satisfy different diffraction conditions among neutrons scattered at an ultra-small angle by the sample 30 Can be detected sequentially.

  The different diffraction conditions are, as described above, a combination of two parameters of the wavelength λ and the scattering angle 2θ, and there are various combinations. By means of a crystal array arranged in series at different angles, scattered neutrons of different wavelengths are detected in sequence by the detector 22.

  The output of the detector 22 is connected to the processor 50, and the scattering intensity (count number) is measured similarly to the small angle scattering detector 11, and the wavelength λ of the neutron is specified by the time of flight method. Since the scattering angle 2θ is known from the detection position at the detector 22, the scattering vector q is obtained.

FIG. 7 is a diagram for explaining the principle of ultra-small angle scattering detection by the crystal array detector 20. As shown in FIG. In FIG. 7, for convenience of illustration, description will be made using five silicon crystals 21-1 to 21-5. The incident planes of the silicon crystals 21-1 to 21-5 are held at different angles θ ₁ , θ ₂ , θ ₃ , θ ₄ , and θ ₅ with respect to the optical axis of the neutron beam.

The scattering vector q _{i of} neutrons scattered by each silicon crystal 21- _i is
q _i = (4π / λ _i ) sin θ _i (4)
Is represented by

Focusing on the silicon crystal 21-3, it is held at an angle of θ ₃ = 49.95 ° with respect to the optical axis, and the lattice spacing (space period d) is 0.31 nm. Formula (2) is exactly
2d * sin θ = nλ (2A)
It is described as Here, n = 1, 1/2, 1/3, 1/4,..., Which represent harmonic components.

The wavelength λ ₃ of the neutrons scattered by the silicon crystal 21-3 and detected by the detector 22 is estimated to be 0.5 nm when n = 1. Scattering vector _{q 3} from the calculated wavelength lambda ₃ and neutrons incident angle theta _3, obtained by the _{q 3 = (4π / λ 3} ) sinθ 3.

When the sensitive length of the electrode (wire) passing the center of the detector 22 is normalized to 1, the ratio Q1 / Q2 of the charges detected at both ends of the electrode is x ₃ / (1−x ₃ ). The detection position x3 of the neutrons scattered by the silicon crystal 21-3 is determined by Q1 / (Q1 + Q2), and it can be specified by which silicon crystal 21 the scattering is performed. Once the angle θ and the wavelength λ are known, the scattering intensity can be plotted as a function of the scattering vector q _i .

  The detection position x may be specified by using a time difference of electric signal generation at both ends of the electrode instead of the ratio of charges at both ends of the electrode. Alternatively, a slit plate made of cadmium (Cd) having a plurality of longitudinal slits may be disposed immediately before each silicon crystal 21 and the detection position may be determined by specifying the trajectory of neutrons.

FIG. 8 shows the measurement results of neutrons scattered by the silicon crystal 21-3. The horizontal axis is time of flight (microseconds), which is proportional to the wavelength of neutrons. The vertical axis is the count number of neutrons. The largest peak in the center is the fundamental count. The second harmonic (lambda _3/2) is disappeared, it does not appear. Write flight time is shorter towards the (left abscissa), third harmonic (lambda _3/3), fourth harmonic (lambda _3/4), the fifth harmonic (lambda _3/5) is detected ing. The fundamental wave of the corresponding wavelength and its harmonics can be extracted by one silicon crystal 21 tilted at a predetermined angle with respect to the optical axis. The fundamental wave contributes to the analysis of large structures. The harmonic components contribute to the improvement of the analysis accuracy of the small structure.

FIG. 9 shows the result of detection by the small angle scattering detector 11 of the device main body 10. As the sample 30, a polymer (block polymer) is used. The horizontal axis is the scattering vector q (Å ⁻¹ ), and the vertical axis is the scattering intensity S (q). Scattering spectra are obtained when the scattering vector q is in the range of 0.007 Å ^{−1 to} 0.5 Å ⁻¹ (7 × 10 ⁻² nm ^{−1 to} 5 nm ⁻¹ ). This corresponds to the wavelength λ ranging from 1 Å (0.1 nm) to 10 Å (1 nm).

The dependence of q ^-4 representing the shape (sphere) of the scatterer appears in the region of 0.05 Å ^-1 to 0.2 Å ^-1 . Several peaks on the q side lower than 0.05 Å ^-1 represent the periodicity of the internal structure of the sample. By arranging the small-angle scattering detector 11, it is possible to analyze the shape and internal structure of a substance having a size (space period d) of several hundred nm.

  FIG. 10 is a diagram showing the effect of extending the analysis range by adding the crystal array detector 20. As shown in FIG. The scattering curve shown by the broken line in FIG. 10 shows the detection result by the crystal array detector 20. By recording the scattering intensity (count number of neutrons) in the processor 50 for each scattering vector q determined by the wavelength λ and the angle θ, the scattering curve of the broken line is obtained.

By combining the crystal array detector 20, neutrons from ultra-small angle scattering are detected, and the lower limit of the scattering vector q is expanded to q ≦ 0.0001 Å ⁻¹ (q ≦ 1 × 10 ⁻³ nm ⁻¹ ). The gentle curve on the smallest side of the magnitude of q represents information about the size (turning radius) around the center of gravity of the particle. By using the small angle scattering detector 11 and the crystal array detector 20 in combination, the shape, size, and internal configuration of a relatively large structure can be analyzed using the same neutron probe (pulsed neutron).

  Small angle scattering is generally suitable for the analysis of fine structures such as the structure of biomolecules (the position of hydrogen molecules in proteins) and inorganic crystal structures. By using the small-angle scattering measurement device 1 according to the embodiment, the range of measurement and analysis can be expanded, and can be used in combination with analysis of a material with a larger space structure.

  For example, rubber products such as tires are filled with particles such as carbon black for the purpose of imparting mechanical strength and preventing deterioration due to ultraviolet light. In opaque thick rubber products, electron beam and long wavelength laser beam are not transmitted, but using the neutron probe (pulsed neutron) of the small angle scattering measurement device 1, the distribution state of carbon black particles having a diameter on the micron order is analyzed can do.

  Although the foregoing has been described based on the specific embodiment, the present invention is not limited to the above-described example. For example, the crystal array detector 20 may be detachably connected by a vacuum connection tube, and may be connected to the device body 10 as needed. The crystal array detector 20 can be applied to any scatterometry device that has a dead zone in the part of the measurement chamber in which the small angle scatter detector is arranged and in which a beam damper is provided.

  The crystal array detector 20 is not limited to the application of neutron scattering measurement, and can be used in combination with small-angle X-ray scattering measurement by combining high-intensity X-rays (radiation light) and an ultrathin film crystal. The X-rays scattered at a very small angle by the sample 30 may be selected by each analyzer crystal (for example, silicon crystal 21) for each wavelength (energy) and detected by the detector 22. In this case, argon (Ar) gas or methane gas may be used as the gas sealed in the detector 22, or a liquid detector, a semiconductor detector, or the like may be used.

  Crystals used as an analyzer in the crystal array detector 20 are not limited to Si crystals, and high purity germanium (Ge) crystal plates with few defects may be used. The number and arrangement intervals of crystal plates constituting the array are appropriately designed according to the sensitive length of the detector, the fineness of wavelength separation, and the like.

  By using the small-angle scattering measurement device 1 of the embodiment, it is possible to cover a wide q range and to measure and analyze a structure from nano level to several microns.

DESCRIPTION OF SYMBOLS 1 small angle scattering measurement apparatus 2 neutron generation target 5 collimator 7 beam damper 10 apparatus main body 19 sample scattering tank 11 small angle scattering detector (first detector)
111 Aperture 112 Neutron Detector 12 Sample Holder 20 Crystal Array Detector (Second Detector)
21, 21-1 to 21-10 Silicon crystal (analyzer crystal)
22 Detector

Claims (10)

A vacuum chamber,
A plurality of analyzer crystals disposed along the optical axis in the vacuum chamber and each held at a different angle to the optical axis;
A detector for detecting the radiation scattered by each of the analyzer crystals;
Have
A crystal array detector characterized in that each of the analyzer crystals scatters by selecting a specific wavelength and a scattering angle from scattered radiation scattered by an external sample and incident on the vacuum chamber. Assuming that the lattice spacing of the analyzer crystal is d, and the angle of the _ith analyzer crystal is θ _i ,
n × λ _i = 2d * sin θ _i
The crystal array detector according to claim 1, wherein the radiation of the wavelength λ _i satisfying the following condition is scattered by the analyzer crystal, and n is 1 / k (k is a natural number).   The crystal array detector according to claim 1 or 2, wherein each of the analyzer crystals is held in the vacuum chamber such that the angles are individually controlled.   The crystal array detector according to any one of claims 1 to 3, wherein the detector is a rod-like detector having a sensing length longer than the arrangement length of the analyzer crystal. An apparatus body comprising a sample holder for holding a sample, and a small angle scatter detector for detecting scattered radiation scattered by the sample;
A crystal array detector disposed downstream of the device body;
Have
The small angle scatter detector has an aperture on the optical axis of incident radiation incident on the device body,
The small-angle scattering measurement apparatus, wherein the crystal array detector detects, among the scattered radiations, scattered radiation of an ultra-small angle which has passed through the opening and entered the crystal array detector.   The crystal array detector has a plurality of analyzer crystals disposed along the optical axis, and incident planes of the plurality of analyzer crystals are held at different angles with respect to the optical axis. The small angle scattering measurement device according to claim 5, characterized in that:   The small-angle scattering measurement apparatus according to claim 6, wherein the crystal array detector comprises a detector that detects the ultra-small-angle scattered radiation scattered by each of the plurality of analyzer crystals.   The small-angle scattering detector includes a first detection layer formed of a plurality of rod-shaped detectors having a major axis in a first direction, and a plurality of major axes in a second direction orthogonal to the first direction. The method according to any one of claims 5 to 7, further comprising: at least a second detection layer formed of a rod-like detector, wherein the opening penetrates the first detection layer and the second detection layer. The small angle scattering measurement device according to item 1. A collimator disposed on the incident side of the device body,
And have
The small-angle scattering measurement device according to any one of claims 5 to 8, wherein the collimator aims at the opening. Irradiate the sample,
Scattered radiation small-angle scattered from the sample is detected by a first detector having an aperture,
Among the scattered radiation, a very small angle of scattered radiation which has passed through the aperture is detected by a second detector in which a plurality of crystals are arranged along an optical axis,
Small angle scattering measurement method characterized by