Electromagnetic wave measurement device, electromagnetic wave measurement method, and electromagnetic wave measurement program

Abstract

An electromagnetic wave measurement device (1) is provided with: an electromagnetic wave irradiation unit (21 and / or 31) that irradiates a sample (S) with electromagnetic waves such as terahertz waves; an electromagnetic wave detection unit (22 and / or 32) that detects electromagnetic waves such as terahertz waves from the sample (S); a recognition unit (51 and / or 52) that recognizes the spatial variation in the internal state and / or shape of the sample (S) on the basis of the electromagnetic waves such as terahertz waves detected by the electromagnetic wave detection unit (22 and / or 32); and a spatial resolution determination unit (53) that determines, on the basis of the spatial variation in the internal state and / or shape, the spatial resolution of an electromagnetic wave such as a terahertz wave to be irradiated to each portion of an object of the same type as the sample (S).

Description

TECHNICAL FIELD

[0001] The present application relates to an electromagnetic wave measuring apparatus such as a spectrometer. BACKGROUND

[0002] In Patent Literature 1, a device is disclosed that measures the internal state of a sample using electromagnetic waves, i.e., terahertz waves, having a frequency in the terahertz (10 12 ) frequency band.

[0003] In an electromagnetic wave measuring apparatus that irradiates electromagnetic waves including terahertz waves to a sample and detects them, the spatial resolution is determined according to the cross-sectional size (hereinafter, also referred to as the beam diameter or the beam size) of the electromagnetic waves. If the beam diameter is large, the spatial resolution becomes low, and if the beam diameter is small, the spatial resolution becomes high.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent No. 6843397 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] If the spatial resolution is lowered, the measurement accuracy becomes low, but there are advantages such as a reduction in the time for scanning the sample. If the spatial resolution is increased, the time for scanning the sample becomes longer, but there are advantages such as an increase in the measurement accuracy. Thus, the setting of the spatial resolution has advantages and disadvantages.

[0009] The present application has been achieved in view of this situation, and aims to provide an electromagnetic wave measuring apparatus and the like that can set an appropriate spatial resolution for each irradiation portion of electromagnetic waves.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] To solve the above problems, an electromagnetic wave measuring apparatus according to an embodiment of the present application includes: an electromagnetic wave irradiation section that irradiates electromagnetic waves to a sample; an electromagnetic wave detection section that detects electromagnetic waves from the sample; an identification section that identifies the internal state of the sample and / or the spatial deviation of the shape, based on the electromagnetic waves detected by the electromagnetic wave detection section; and a spatial resolution determination section that determines the spatial resolution of the electromagnetic waves that should be irradiated to each portion of an object of the same kind as the sample, based on the spatial deviation of the internal state and / or the shape.

[0012] In this mode, the spatial resolution of the electromagnetic wave that should be irradiated to each portion of an object of the same kind as the sample is determined in accordance with the spatial deviation of the internal state and / or shape of the sample identified by the electromagnetic wave. For example, a higher spatial resolution is set for a portion in the sample where the spatial deviation of the internal state and / or shape is large, and a lower spatial resolution is set for a portion in the sample where the spatial deviation of the internal state and / or shape is small.

[0013] Another embodiment of the present application is an electromagnetic wave measurement method. The method includes: an electromagnetic wave irradiation step of irradiating a sample with an electromagnetic wave; an electromagnetic wave detection step of detecting the electromagnetic wave from the sample; an identification step of identifying a spatial deviation of an internal state and / or shape of the sample based on the electromagnetic wave detected in the electromagnetic wave detection step; and a spatial resolution determination step of determining a spatial resolution of the electromagnetic wave that should be irradiated to each portion of an object of the same kind as the sample based on the spatial deviation of the internal state and / or shape.

[0014] In addition, any combination of the above configuration elements or contents of converting these expressions into a method, device, system, storage medium, computer program, and the like are also included in the present application.

[0015] Effects of Invention

[0016] According to the present application, an appropriate spatial resolution can be set for each irradiation portion of the electromagnetic wave. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is an electromagnetic wave measurement device that shows a preliminary measurement on a sample.

[0018] Figure 2 is an electromagnetic wave measurement device that shows a formal measurement on an object.

[0019] Figure 3 is a specific example showing a determination process of the spatial resolution by the spatial resolution determination section.

[0020] Figure 4 is an example showing a beam size variable technique.

[0021] Figure 5 is another example showing a beam size variable technique.

[0022] Figure 6 is a flowchart showing an example of a process of a preliminary measurement on a sample and a formal measurement on an object by an electromagnetic wave measurement device. DETAILED DESCRIPTION

[0023] Hereinafter, a mode for carrying out the present application (hereinafter, also referred to as an embodiment) will be described in detail with reference to the drawings. In the description and / or the drawings, the same or equivalent constituent elements, members, processes, etc. are denoted by the same reference numerals, and repeated description will be omitted. The proportions or shapes of the parts shown in the drawings are set for the convenience of explanation, and are not to be construed limitatively unless otherwise specified. The embodiments are examples, and do not limit the scope of the present application in any way. All features recited in the embodiments and combinations thereof are not necessarily essential to the present application.

[0024] Figure 1 and Figure 2 The structure of an electromagnetic wave measuring apparatus 1 according to an embodiment of the present application is schematically shown. The measurement mode or purpose of the electromagnetic wave measuring apparatus 1 is not particularly limited, and for example, the internal state such as residual stress, strain, orientation, deterioration, etc. in an object O to be measured is evaluated based on the anisotropy of the refractive index and / or the anisotropy of the dielectric constant of the object O.

[0025] Figure 1 The electromagnetic wave measuring apparatus 1 is shown which performs preliminary measurement on a sample S. Figure 2 The electromagnetic wave measuring apparatus 1 is shown which performs formal measurement on an object O of the same kind as the sample S. The sample S and the object O are, for example, substantially identical products (for example, resin molded products) manufactured by the same manufacturing apparatus (for example, an injection molding machine) and / or the same manufacturing method. That is, the sample S and the object O belong to the same product group. The sample S is one or a small number of products extracted from the product group for preliminary measurement. The formal measurement performed on the object O, which is usually a large number of objects belonging to the same product group as the sample S, is performed based on the control parameters (beam size or beam movement amount) adjusted based on the preliminary measurement result of the sample S.

[0026] In Figure 1 The electromagnetic wave measuring apparatus 1 has an internal state measuring apparatus 2, a shape measuring apparatus 3, a control section 4, a calculation section 5, and a storage section 6. As long as the electromagnetic wave measuring apparatus 1 can achieve at least a part of the effects and / or advantages described below, a part of these functional modules can be omitted. These functional modules are realized by the cooperation of hardware resources such as a central calculation processing device, a memory, an input device, an output device, and a peripheral device connected to a computer, and software executed by using them. Regardless of the kind or the setting position of the computer, each of the above-mentioned functional modules can be realized by the hardware resources of a single computer, or can be realized by combining the hardware resources dispersed in a plurality of computers.

[0027] The internal state measuring device 2 measures the internal state of the sample S, such as internal stress, by irradiating the sample S located at the internal state measuring position P1 with electromagnetic waves. Specifically, the internal state measuring device 2 includes an electromagnetic wave irradiation unit 21 that irradiates the sample S located at the internal state measuring position P1 with electromagnetic waves, and an electromagnetic wave detection unit 22 that detects the electromagnetic waves from the sample S. The electromagnetic waves irradiated by the electromagnetic wave irradiation unit 21 have any frequency suitable for measuring the internal state of the sample S and the object O.

[0028] In this embodiment, terahertz waves with frequencies in the terahertz band are used as the electromagnetic waves for measurement. Terahertz waves possess intermediate properties between low-frequency radio waves and high-frequency light; for example, they can penetrate polymer materials that ordinary light cannot, just like radio waves. Furthermore, terahertz waves are strongly influenced by absorption caused by inherent vibrations in polymer materials such as biomolecules. Based on these characteristics, terahertz waves are preferably used for spectroscopic measurements of polymer materials. And, as regarding… Figure 4 The terahertz time-domain spectroscopy method, described later, is capable of operating over a wide frequency band (in... Figure 4 In the example, measurements were performed over a frequency bandwidth of approximately 1-3 THz. Given the low frequency dependence of the measurements within this wide bandwidth, terahertz waves allow for easy adjustment of the beam size by selecting the frequency range, making them suitable for... Figure 2 The control of beam size during formal measurements.

[0029] The electromagnetic wave irradiation unit 21 irradiates terahertz waves onto the measurement position on the sample S, as specified by the measurement position control unit 41 in the control unit 4. (As described later...) Figure 2 The formal measurement in China is different, when conducting... Figure 1 During the preliminary measurement, the electromagnetic wave irradiation unit 21 irradiates the sample S with terahertz waves at a constant beam size. Thus, during the preliminary measurement, the spatial resolution of the terahertz waves, determined by the beam size, is constant. Hereinafter, this constant spatial resolution during the preliminary measurement is also referred to as the reference spatial resolution. To precisely perform the spatial resolution determination process of the spatial resolution determination unit 53 in the calculation unit 5 (described later), the reference spatial resolution during the preliminary measurement is preferably the highest spatial resolution achievable by the internal state measurement device 2. In other words, the electromagnetic wave irradiation unit 21 irradiates the sample S with the smallest achievable beam size. The measurement position control unit 41 performs a two-dimensional scan so that the terahertz waves with a constant (preferably minimum) beam size from the electromagnetic wave irradiation unit 21 sequentially irradiate substantially the entire surface of the sample S.

[0030] The electromagnetic wave detection section 22 sequentially detects the terahertz waves from each measurement position or each irradiation position on the sample S. The electromagnetic wave detection section 22 in the illustrated example is disposed on the side opposite to the electromagnetic wave irradiation section 21 with respect to the sample S on the internal state measurement position PI, and thus detects the terahertz waves transmitted through the sample S. However, the electromagnetic wave detection section 22 can also be disposed on the same side as the electromagnetic wave irradiation section 21 with respect to the sample S on the internal state measurement position PI, and detect electromagnetic waves such as terahertz waves reflected from the sample S.

[0031] The electromagnetic wave detection section 22 supplies the detection result of the terahertz waves to the internal state recognition section 51 in the arithmetic section 5. The internal state recognition section 51 recognizes the internal state such as the internal stress of each measurement position on the sample S, based on the detection result supplied from the electromagnetic wave detection section 22. For example, by using the technology disclosed in Patent Literature 1 (including the background art thereof), it is possible to recognize the internal state of the sample S from the detection result of the terahertz waves (or electric waves). Also, in the case where the internal state measurement apparatus 2 uses general light other than terahertz waves, the internal state recognition section 51 can recognize the internal state of the sample S based on the detection result of the light, for example, by using a known spectroscopic measurement (spectrum measurement) technology.

[0032] The shape measurement apparatus 3 measures the shape of the surface or the like of the sample S on the shape measurement position P2 different from the internal state measurement position PI. The surface shape of the sample S measured by the shape measurement apparatus 3 can be the designed shape of the sample S itself, or a shape deviating from the designed shape due to a manufacturing error. The shape measurement apparatus 3 is not limited as long as it can directly or indirectly measure the external shape of the sample S. As an example, like the internal state measurement apparatus 2, the shape measurement apparatus 3 can also measure the shape of the sample S by irradiating the sample S on the shape measurement position P2 with electromagnetic waves.

[0033] The internal state measurement apparatus 2 and the shape measurement apparatus 3 at this time can be configured as a single measurement apparatus using electromagnetic waves. At this time, the internal state measurement position PI and the shape measurement position P2 are the same. However, the frequency of the electromagnetic waves used for measuring the internal state of the sample S can be different from the frequency of the electromagnetic waves used for measuring the shape of the sample S. For example, a terahertz wave or an electric wave of a low frequency (compared to light) that can transmit through the sample S can be used for the measurement of the internal state of the sample S, and light such as visible light of a high frequency (compared to an electric wave) that reflects or scatters according to the shape of the sample S can be used for the measurement of the shape of the sample S.

[0034] In the case where the shape measuring device 3 uses electromagnetic waves, an electromagnetic wave irradiation section 31 and an electromagnetic wave detection section 32 (both illustrated as "shape measuring sections") are provided similarly to the electromagnetic wave irradiation section 21 and the electromagnetic wave detection section 22 in the internal state measuring device 2. The electromagnetic wave irradiation section 31 irradiates electromagnetic waves to the sample S located on a shape measuring position P2, and the electromagnetic wave detection section 32 detects electromagnetic waves from the sample S. As described above, the electromagnetic waves irradiated by the electromagnetic wave irradiation section 31 have an arbitrary frequency suitable for measuring the external shape of the sample S.

[0035] The electromagnetic wave irradiation section 31 irradiates electromagnetic waves to a measuring position on the sample S designated by a measuring position control section 41 in the control section 4. In the case where the electromagnetic wave irradiation section 31 irradiates electromagnetic waves to the sample S, the measuring position control section 41 performs a two-dimensional scan so that the electromagnetic waves irradiated from the electromagnetic wave irradiation section 31 are sequentially irradiated to substantially the entire surface of the sample S. Figure 1 In the preliminary measurement in the internal state measuring device 2, the electromagnetic wave irradiation section 21 irradiates electromagnetic waves to the sample S with a constant beam size. Here, the constant beam size of the electromagnetic wave irradiation section 21 is preferably equal to or smaller than the constant beam size of the electromagnetic wave irradiation section 31. Hereinafter, for the sake of simplicity, the constant beam size used in the preliminary measurement by the electromagnetic wave irradiation section 21 and the electromagnetic wave irradiation section 31 is substantially equal. In other words, the reference spatial resolution in the preliminary measurement by the internal state measuring device 2 and the shape measuring device 3 is substantially equal (preferably, the highest spatial resolution that can be achieved by the internal state measuring device 2 and / or the shape measuring device 3). The measuring position control section 41 performs a two-dimensional scan so that the electromagnetic waves with the constant (preferably, the smallest) beam size from the electromagnetic wave irradiation section 31 are sequentially irradiated to substantially the entire surface of the sample S.

[0036] The electromagnetic wave detection section 32 sequentially detects electromagnetic waves from each measuring position or each irradiation position on the sample S. The electromagnetic wave detection section 32 in the illustrated example is provided on the side opposite to the electromagnetic wave irradiation section 31 with respect to the sample S on the shape measuring position P2, and thus detects electromagnetic waves transmitted through the sample S. However, the electromagnetic wave detection section 32 can be provided on the same side as the electromagnetic wave irradiation section 31 with respect to the sample S on the shape measuring position P2, and detect electromagnetic waves reflected from the sample S. Also, in the case where the electromagnetic waves measured by the shape measuring device 3 cannot be transmitted through the sample S, the shape measuring sections 31 and 32 (e.g., image sensors) can be respectively provided on the front side (e.g., the side of the face in Figure 1 the internal state measuring device 2) and the back side (e.g., the side of the back in Figure 1 the internal state measuring device 2) of the sample S, and respectively detect electromagnetic waves such as light reflected or scattered due to the shape of the front and back surfaces of the sample S. The shape measuring device 3 provides the measurement result of the shape of the sample S to the shape recognition section 52 in the arithmetic section 5.

[0037] As described above, the internal state measuring device 2 and the shape measuring device 3 are provided in the measurement system 1. The internal state measuring device 2 and the shape measuring device 3 are configured to measure the internal state and the shape of the sample S, respectively, and the measurement results are provided to the arithmetic section 5. Figure 1In the case where the internal state measuring device 2 and the shape measuring device 3 are different devices, and the positions at which each is disposed (the internal state measuring position PI and the shape measuring position P2) are different, a sample driving section 42 is provided which moves the sample S, which is the measurement object of the two devices, between the internal state measuring position PI at which the electromagnetic wave irradiation section 21 and the electromagnetic wave detection section 22 are disposed, and the shape measuring position P2 at which the shape measuring device 3 (the electromagnetic wave irradiation section 31 and the electromagnetic wave detection section 32) is disposed. In Figure 1 In the preliminary measurement of the sample S in the above-described embodiment, the two kinds of measurement, the measurement of the internal state based on the internal state measuring device 2 at the internal state measuring position PI, and the measurement of the shape based on the shape measuring device 3 at the shape measuring position P2, are sequentially performed; during each measurement, the sample driving section 42 drives the sample S from one of the internal state measuring position PI and the shape measuring position P2 to the other. The sample driving section 42 drives the sample S between the internal state measuring position PI and the shape measuring position P2, for example, by driving the movable stage 7 on which the sample S is placed.

[0038] The control section 4 is provided with the above-described measurement position control section 41 and the sample driving section 42. An arithmetic section 5 constituted by the same or different computer or processor as the control section 4 is provided with an internal state recognition section 51, a shape recognition section 52, a spatial resolution determination section 53, a beam size setting section 54, a beam movement amount setting section 55, and an internal state analysis section 56. Figure 2

[0039] The internal state recognition section 51 and / or the shape recognition section 52 constitute a recognition section which recognizes the spatial deviation of the internal state and / or the shape of the sample S from the electromagnetic wave detected by the electromagnetic wave detection section 22 and / or 32. Specifically, the internal state recognition section 51 recognizes the spatial deviation of the internal state of the sample S from the electromagnetic wave such as a terahertz wave detected by the electromagnetic wave detection section 22, and the shape recognition section 52 recognizes the spatial deviation of the shape of the sample S from the electromagnetic wave (which can also be a terahertz wave) detected by the electromagnetic wave detection section 32. The spatial resolution determination section 53 determines the spatial resolution of the electromagnetic wave such as a terahertz wave which should be irradiated to each portion of the object O (which is the same kind of object as the sample S) from the spatial deviation of the internal state recognized by the internal state recognition section 51 and / or the shape recognized by the shape recognition section 52. Figure 2

[0040] Figure 3 A specific example of the determination processing of the spatial resolution performed by the spatial resolution determination section 53 is shown. In Figure 3 ​​In Figures A and B, the results of a preliminary measurement of the internal stress of sample S by the internal state measuring device 2 are schematically shown by contour lines. The side lengths of the square pixels or cells in both figures correspond to the constant reference spatial resolution of the terahertz wave or the like used in the preliminary measurement. Alternatively, the size of each pixel corresponds to the constant beam size of the terahertz wave or the like used in the preliminary measurement.

[0041] exist Figure 3 In Figure A, the spatial resolution determination unit 53 determines an appropriate spatial resolution using a pixel labeled "Region A" as the object. At this time, the spatial resolution determination unit 53, for example, refers to a pixel group including "Region B" which is "Region A". Specifically, if the deviation of internal stress in "Region A" and "Region B" (identified by the internal state recognition unit 51) and / or the deviation of shape in "Region A" and "Region B" (identified by the shape recognition unit 52) ​​is below a predetermined threshold (a first threshold for spatial deviation of internal stress and / or a second threshold for spatial deviation of shape), the spatial resolution determination unit 53 will irradiate the object O (…). Figure 2 The spatial resolution of electromagnetic waves such as terahertz waves in "Region A" is set to be lower than the reference spatial resolution.

[0042] The result, such as Figure 3 As shown in Figure B, in the formal measurement of object O, electromagnetic waves such as terahertz waves with a larger beam size (i.e., lower spatial resolution than the reference spatial resolution) are irradiated onto "region A". Figure 3 The spatial deviations in internal stress and / or shape of sample S in Figure A, which are related to "Region A" at the reference spatial resolution, are small (below a predetermined threshold). Therefore, even if... Figure 3 As shown in Figure B, "region A" is "enlarged," allowing for proper formal measurement of object O. Thus, according to this embodiment, for portions of object O where a decrease in measurement accuracy has a relatively minor impact, measurement time can be shortened by reducing spatial resolution (increasing beam size).

[0043] On the other hand, Figure 3 If the internal stress and / or shape deviation in "Region A" and "Region B" of Figure A exceeds a predetermined threshold, the spatial resolution determination unit 53 will illuminate the object O ( Figure 2 The spatial resolution of electromagnetic waves such as terahertz waves in "Region A" is maintained at the (highest) reference spatial resolution. Thus, according to this embodiment, for parts of the object O where the reduction in measurement accuracy is significant, measurement accuracy can be maintained by increasing the spatial resolution (reducing the beam size).

[0044] The spatial resolution determination unit 53 sequentially performs the following steps on virtually all pixels on the sample S: Figure 3 The process for determining the spatial resolution of the example "Region A" is described. The result is as follows: Figure 3 In the pixel map of the object O (or sample S) shown, the spatial resolution applied to each pixel is set separately.

[0045] The beam size setting unit 54 sets the spatial resolution determined by the spatial resolution determining unit 53 for each pixel in the target object O to the standard setting for the actual measurement. Figure 2 The beam size of electromagnetic waves such as terahertz waves irradiating each pixel is determined by the spatial resolution determined by the spatial resolution determination unit 53 and / or the beam size set by the beam size setting unit 54. The beam movement setting unit 55 sets the amount of beam movement, such as terahertz waves, during the two-dimensional scanning of the object O in the actual measurement, based on the spatial resolution determined by the spatial resolution determination unit 53 and / or the beam size set by the beam size setting unit 54. For example, in the area where a reference spatial resolution is applied (an area with large spatial deviations in internal stress and / or shape), the beam movement setting unit 55 sets a beam movement of 1 pixel per movement. Furthermore, as... Figure 3 In Figure B, "Region A" is a region with a lower spatial resolution than the reference spatial resolution (a region with smaller spatial deviations in internal stress and / or shape). The beam movement amount setting unit 55 sets a beam movement amount of multiple pixels (equivalent to...) within this region. Figure 3 (The length of the side of “Region A” in Figure B).

[0046] The beam size of each pixel set by the beam size setting unit 54 and the beam movement during two-dimensional scanning set by the beam movement setting unit 55 are used as the formal measurement on the object O. Figure 2 The control information used in the ) is stored in storage unit 6.

[0047] Figure 2 The electromagnetic wave measuring device 1 in the middle performs measurement based on the control information (beam size and beam movement) stored in the storage unit 6, and compares the beam with the electromagnetic wave measurement information stored in the storage unit 6. Figure 1 The sample S to be measured is the same type of object O as the object to be formally measured. Figure 2 In the electromagnetic wave measuring device 1, there are an internal state measuring device 2, a control unit 4, a calculation unit 5, and a storage unit 6.

[0048] Internal state measuring device 2 can be connected with Figure 1The apparatus used for preliminary measurement can be the same as or different from that used in the previous measurement. The internal state measuring device 2 measures the internal state of the object O, such as internal stress, by irradiating it with electromagnetic waves. Specifically, the internal state measuring device 2 includes an electromagnetic wave irradiation unit 21 that irradiates electromagnetic waves onto the object O and an electromagnetic wave detection unit 22 that detects the electromagnetic waves from the object O. The electromagnetic waves irradiated by the electromagnetic wave irradiation unit 21 have an arbitrary frequency suitable for measuring the internal state of the object O. Preferably, the internal state measuring device 2 is equipped with an electromagnetic wave irradiation unit 21 that irradiates electromagnetic waves onto the object O. Figure 1 The terahertz waves used in the preliminary measurement are essentially the same as those used in the measurement of electromagnetic waves.

[0049] The electromagnetic wave irradiation unit 21 irradiates terahertz waves onto the measurement position on the object O specified by the measurement position control unit 41 in the control unit 4. (This is in contrast to the above.) Figure 1 The preparatory measurements differ from those taken during the initial measurement process. Figure 2 During the formal measurement, the electromagnetic wave irradiation unit 21 irradiates the object O with terahertz waves of variable beam size for each measurement position (pixel). Therefore, a beam size control unit 43, which serves as an electromagnetic wave size control unit, is provided in the control unit 4. The beam size control unit 43 controls the beam size of the electromagnetic waves irradiated by the electromagnetic wave irradiation unit 21 at each measurement position of the object O based on the spatial resolution determined by the spatial resolution determination unit 53 based on the preliminary measurement of the sample S. Specifically, the beam size control unit 43 utilizes the beam size of each measurement position (pixel) stored in the storage unit 6. Since the measurement position or irradiation position of the electromagnetic wave irradiation unit 21 can be obtained from the measurement position control unit 41 in the same control unit 4, the beam size control unit 43 can apply the beam size corresponding to that measurement position (pixel) to the electromagnetic wave irradiation unit 21.

[0050] like Figure 3 As described above, in areas where the spatial deviations in internal stress and / or shape of the sample S and the object O are large, the highest reference spatial resolution is typically applied. Therefore, the beam size control unit 43 typically applies the smallest beam size to the electromagnetic wave irradiation unit 21. Furthermore, in areas where the spatial deviations in internal stress and / or shape of the sample S and the object O are small, such as... Figure 3 In Figure B, "Region A" uses an adjusted spatial resolution lower than the reference spatial resolution. Therefore, the beam size control unit 43 will set a beam size larger than the minimum beam size (in...). Figure 3 In the example of Figure B, 9 pixels are used in the electromagnetic wave irradiation section 21.

[0051] Figure 4An example of a beam-size variable technology for applications such as terahertz waves is shown, where the beam size control unit 43 and the electromagnetic wave irradiation unit 21 are configured. This technology is based on Huygens' principle, utilizing the characteristic that the rectilinear propagation of diffracted electromagnetic waves varies with frequency. Higher frequency electromagnetic waves have stronger rectilinear propagation, while lower frequency electromagnetic waves have weaker rectilinear propagation. For example... Figure 4 As illustrated, choosing a relatively high frequency band (approximately 2-3 THz in the illustrated example) results in stronger linear propagation of the beam and a smaller beam diameter. Conversely, choosing a relatively low frequency band (approximately 1-3 THz in the illustrated example) results in weaker linear propagation of the beam and a larger beam diameter. Additionally, Figure 4 In this context, "parallel" and "perpendicular" represent the polarization directions of terahertz waves, respectively.

[0052] Figure 5 Another example of variable beam size technology is shown. In this example, an aperture mechanism 23 or aperture for controlling the beam size is disposed between the electromagnetic wave irradiation unit 21 and the object O. The beam size control unit 43 controls the opening size of the aperture mechanism 23 according to the beam size stored in the storage unit 6 for each measurement position (pixel), thereby controlling the size of the beam irradiating the object O.

[0053] As another example of variable beam size technology, when the electromagnetic wave irradiation unit 21 and / or the electromagnetic wave detection unit 22 are composed of multiple elements in an array, the beam size control unit 43 controls the actual number of elements used to achieve the same effect as controlling the beam size irradiated on the target object O.

[0054] and Figure 1 Similar to the preliminary measurement, the measurement position control unit 41 performs a two-dimensional scan so that terahertz waves with variable beam sizes from the electromagnetic wave irradiation unit 21 sequentially irradiate substantially the entire surface of the object O. The amount of beam movement during the two-dimensional scan is always one pixel at a time in the preliminary measurement, which always uses a reference spatial resolution of one pixel. However, in the actual measurement, the beam size is variable via the beam size control unit 43, and is therefore controlled accordingly by the measurement position control unit 41. For example, in... Figure 3 In Figure B, "Region A," in an area where the adjusted spatial resolution is lower than the reference spatial resolution, the measurement position control unit 41 applies a beam movement amount of multiple pixels to the internal state measurement device 2. Figure 1 The beam movement amount is set and stored in the storage unit 6 for each measurement position (pixel), and the beam movement amount control in the two-dimensional scanning described above is performed.

[0055] The electromagnetic wave detection section 22 sequentially detects terahertz waves from each measurement position or each irradiation position on the object O. The electromagnetic wave detection section 22 in the illustrated example is provided on the side opposite to the electromagnetic wave irradiation section 21 with respect to the object O, and thus detects terahertz waves that have transmitted through the object O. However, the electromagnetic wave detection section 22 can also be provided on the same side as the electromagnetic wave irradiation section 21 with respect to the object O, and detect electromagnetic waves such as terahertz waves that have reflected from the object O.

[0056] The detection result of the terahertz waves in the electromagnetic wave detection section 22 is provided to the internal state analysis section 56 in the arithmetic section 5. The internal state analysis section 56 can be the same as the internal state identification section 51 utilized at the time of the preliminary measurement in Figure 1 The internal state analysis section 56 identifies the internal stress and the like on the internal state on each measurement position on the object O, based on the detection result provided from the electromagnetic wave detection section 22. In addition, the internal state analysis section 56 also refers to the beam size information (or the frequency band information for controlling the beam size) of each measurement position (pixel) stored in the storage section 6, in the analysis of the internal state of the object O.

[0057] Figure 6 is a flowchart showing an example of the processing based on the preliminary measurement of the sample S and the formal measurement of the object O by the electromagnetic wave measurement apparatus 1 according to the present embodiment. In this drawing, the preliminary measurement and the formal measurement are shown as a series of processes in one flowchart, but the preliminary measurement and the formal measurement can be performed as different processes on different dates and times, for example. In addition, "S" in the flowchart indicates a step or a process. S1 to S11 are processes of the preliminary measurement of the sample S Figure 1 ), and S12 is a process of the formal measurement of the object O Figure 2 ).

[0058] In S1, the shape measurement apparatus 3 measures the shape of the sample S located on the shape measurement position P2. As described above, the spatial resolution in S1 is the highest reference spatial resolution and is constant. "Xmin" is the minimum distance that can be identified at this reference spatial resolution, and corresponds to the length of the side of the square-shaped pixel in Figure 3 After S1, the sample S is driven from the shape measurement position P2 to the internal state measurement position PI by the sample drive section 42. In S2, the internal state measurement apparatus 2 measures the internal state of the sample S by irradiating electromagnetic waves such as terahertz waves on the sample S located on the internal state measurement position PI. As described above, the spatial resolution in S2 is the highest reference spatial resolution and is constant, and is equal to the spatial resolution in S1. In addition, S2 can be performed first, and then S1 can be performed.

[0059] In S3, the spatial resolution determination section 53 selects the spatial resolution to be used in the formal measurement of the object O, as described in Figure 3One pixel shown as an object of the determination processing of the spatial resolution is taken as "Region A", and "Region B" containing it is set. In S4, the spatial resolution determination section 53 evaluates the spatial deviation of the internal state of the plurality of pixels within "Region B" recognized by the internal state recognition section 51 from the measurement result of S2. In S5, the spatial resolution determination section 53 determines whether the spatial deviation of the internal state of the plurality of pixels within "Region B" in S4 is equal to or less than a predetermined first threshold value. In the case where it is determined as "Yes" in S5, the internal state within "Region B" is substantially uniform, and S7 is entered. In the case where it is determined as "No" in S5, the internal state within "Region B" is not uniform, and S6 is entered.

[0060] In S6, the spatial resolution determination section 53 determines whether the difference between the average value of the internal state parameter (internal stress, etc.) within "Region A" and the average value of the internal state parameter within "Region B" is equal to or less than a predetermined third threshold value. In the case where it is determined as "Yes" in S6, the internal state substantially linearly changes from "Region A" to "Region B", and the processing equivalent to the case where it is "Yes" in S5 is also acceptable, and thus S7 is entered. In the case where it is determined as "No" in S6, the internal state nonlinearly changes from "Region A" to "Region B", and if "Region A" is expanded as in S9 described later, the measurement accuracy can greatly deteriorate, and thus S10 is entered, and "Region A" is determined without expansion. Figure 3 In the case where it is determined as "No" in S6, "Region A" is not expanded, and the internal state parameter (internal stress, etc.) of the pixel of "Region A" is determined as the minimum region in the initial state shown in Fig. A in

[0061] In S7, the spatial resolution determination section 53 evaluates the spatial deviation (height difference, etc.) of the shape of the plurality of pixels within "Region B" recognized by the shape recognition section 52 from the measurement result of S1. In S8, the spatial resolution determination section 53 determines whether the spatial deviation of the shape of the plurality of pixels within "Region B" in S7 is equal to or less than a predetermined second threshold value. In the case where it is determined as "Yes" in S8, the shape within "Region B" is substantially uniform, and S9 is entered. In the case where it is determined as "No" in S8, the shape within "Region B" is not uniform (for example, a concave-convex shape), and if "Region A" is expanded as in S9 described later, the measurement accuracy can greatly deteriorate, and thus S10 is entered, and "Region A" is determined without expansion.

[0062] In S9, as the change from Fig. A to Fig. B in Figure 3 In S9, as the change from Fig. A to Fig. B in Figure 3"Region B" of FIG. A) in S10. Then, a new "Region B" containing the expanded "Region A" is set. Thereafter, the processes of S4 to S9 are repeated until "Region A" is determined in S10. In S11, it is determined whether or not the evaluation of all pixels on the sample S (determination of the spatial resolution by the spatial resolution determination section 53) is completed. In the case where it is determined "No" in S11, the processes of S3 to S10 are repeated until it is determined "Yes" in S11. If it is determined "Yes" in S11, the preliminary measurement of the sample S ends. In the following S12, the formal measurement of the object O is performed by the internal state measurement device 2 or the like in accordance with the spatial resolution on each pixel or each measurement position determined in S10.

[0063] The present application has been described above according to the embodiments. The combination of each constituent element or each process in the embodiments as examples can have various modifications, and such modifications are included in the scope of the present application, as is apparent to those skilled in the art.

[0064] In addition, the configuration, action, and function of each device or each method described in the embodiments can be realized by a hardware resource or a software resource, or by a cooperation of a hardware resource and a software resource. As the hardware resource, for example, a processor, a ROM, a RAM, and various integrated circuits can be used. As the software resource, for example, an operating system, an application, and the like can be used.

[0065] Industrial Applicability

[0066] The present application relates to an electromagnetic wave measurement device such as a spectrometer and the like.

[0067] Explanation of Symbols

[0068] 1 - electromagnetic wave measurement device, 2 - internal state measurement device, 3 - shape measurement device, 6 - storage section, 21 - electromagnetic wave irradiation section, 22 - electromagnetic wave detection section, 23 - diaphragm mechanism, 41 - measurement position control section, 42 - sample drive section, 43 - beam size control section, 51 - internal state recognition section, 52 - shape recognition section, 53 - spatial resolution determination section, 54 - beam size setting section, 55 - beam movement amount setting section, 56 - internal state analysis section, P1 - internal state measurement position, P2 - shape measurement position.

Claims

1. An electromagnetic wave measuring apparatus comprising: an electromagnetic wave irradiation section that irradiates an electromagnetic wave to a sample; an electromagnetic wave detection section that detects the electromagnetic wave from the sample; an identification section that identifies a spatial deviation of an internal state and / or a shape of the sample based on the electromagnetic wave detected by the electromagnetic wave detection section; and a spatial resolution determination section that determines a spatial resolution of the electromagnetic wave that should be irradiated to each portion of an object of the same kind as the sample based on the spatial deviation of the internal state and / or the shape.

2. The electromagnetic wave measuring apparatus according to claim 1, wherein the electromagnetic wave irradiation section irradiates the electromagnetic wave of a reference spatial resolution to the sample, and the spatial resolution determination section sets the spatial resolution of the electromagnetic wave that should be irradiated to a portion where the spatial deviation of the internal state and / or the shape is below a threshold to be lower than the reference spatial resolution.

3. The electromagnetic wave measuring apparatus according to claim 1, comprising: an internal state identification section that identifies the spatial deviation of the internal state of the sample; and a shape identification section that identifies the spatial deviation of the shape of the sample, wherein the spatial resolution determination section determines the spatial resolution based on the spatial deviations of the internal state and the shape.

4. The electromagnetic wave measuring apparatus according to claim 3, wherein the electromagnetic wave irradiation section irradiates the electromagnetic wave of a reference spatial resolution to the sample, and the spatial resolution determination section sets the spatial resolution of the electromagnetic wave that should be irradiated to a portion where the spatial deviation of the internal state is below a first threshold and the spatial deviation of the shape is below a second threshold to be lower than the reference spatial resolution.

5. The electromagnetic wave measuring apparatus according to claim 3, comprising: a sample driving section that moves the sample between an internal state measurement position where the electromagnetic wave irradiation section and the electromagnetic wave detection section are provided and a shape measurement position where the shape is measured.

6. The electromagnetic wave measuring apparatus according to any one of claims 1 to 5, comprising: an electromagnetic wave size control section that controls a size of the electromagnetic wave irradiated by the electromagnetic wave irradiation section to the object based on the spatial resolution determined by the spatial resolution determination section.

7. The electromagnetic wave measuring apparatus according to any one of claims 1 to 5, wherein the electromagnetic wave is a terahertz wave.

8. The electromagnetic wave measuring apparatus according to any one of claims 1 to 5, wherein the internal state includes an internal stress of the sample.

9. An electromagnetic wave measuring method comprising: an electromagnetic wave irradiation step of irradiating an electromagnetic wave to a sample; an electromagnetic wave detection step of detecting the electromagnetic wave from the sample; an identification step of identifying a spatial deviation of an internal state and / or a shape of the sample based on the electromagnetic wave detected in the electromagnetic wave detection step; and a spatial resolution determination step of determining a spatial resolution of the electromagnetic wave that should be irradiated to each portion of an object of the same kind as the sample based on the spatial deviation of the internal state and / or the shape.

10. An electromagnetic wave measuring program that causes a computer to execute the following steps: an electromagnetic wave irradiation step of irradiating an electromagnetic wave to a sample; ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ an electromagnetic wave detecting step of detecting the electromagnetic wave from the sample; an identifying step of identifying a spatial deviation of an internal state and / or a shape of the sample based on the electromagnetic wave detected in the electromagnetic wave detecting step; and a spatial resolution determining step of determining a spatial resolution of the electromagnetic wave that should be irradiated to each portion of an object of the same kind as the sample based on the spatial deviation of the internal state and / or the shape. ​

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