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Sensors and Materials, Vol. 36, No. 8 (2024) 3465–3477
MYU Tokyo
S & M 3745

Consideration of Experiment to Introduce MEMS Devices
into Spectroscopic Systems
for Bending and Three-point Tension Tests
Akinobu Yamaguchi,1,4* Takuo Ohkochi,2,3,4 Masaki Oura,4Tokuji Yokomatsu,5 and Kensuke Kanda5
1Department of Electrical, Electronic and Communications Engineering, Faculty of Science and Engineering, Toyo

University, 2100 Kujirai, Kawagoe-city, Saitama 350-8585, Japan

2Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 3-1-2 Kouto, Kamigori,

Hyogo 678-1205, Japan

3Japan Synchrotron Radiation Research Institute, 1-1-1 Koto, Sayo, Hyogo 679–5198, Japan
4RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-gun, Hyogo 679–5148, Japan

5Graduate School of Engineering, University of Hyogo, Shosha, Himeji, Hyogo 671-2280, Japan(Received June 3, 2024; accepted July 3, 2024)

Keywords: MEMS, micro-Raman spectroscopy, PEEM, synchrotron radiation

Recently, material strength measurements have been often performed by combining
mechanical material characterization and lattice diffraction experiments using hard X-rays.
When X-ray diffraction experiments are performed simultaneously with tensile tests, plastic
deformation due to stress can be analyzed at the lattice level. Although this evaluation procedure
is suitable for materials such as metals, it does not provide information on molecular statechanges and stress-induced electronic state transitions in polymer materials. Combined with anevaluation system in the electron energy band involved in chemical bonding during the tensilestress application, the systems would advance our understanding of adhesion states such as
interfaces in polymer materials and composites. Here, we developed a MEMS-based system
aimed at implementing a Raman spectroscopy imaging system and a stress control system on asoft X-ray absorption spectroscopy and photoelectron spectroscopy microscopy (PEEM) system.
We prepared two types of MEMS device: a double-sided beam structure device and a threepoint tensile testing device. A three-point tensile MEMS was integrated into a micro-Raman
spectroscopy system to perform micro-Raman spectroscopy measurements during the tensile
testing of a silicon beam. As for the double-sided beam structure MEMS, it was successfully
introduced into the synchrotron radiation PEEM system and its operation was confirmed in
vacuum.

1.

Introduction

In recent years, there have been many reports on the creation of novel materials such asgraphene(1) and topological insulators(2) that are very interesting and have potential applications*Corresponding author: e-mail: yamaguchi054@toyo.jp

https://doi.org/10.18494/SAM5169

ISSN 0914-4935 © MYU K.K.
https://myukk.org/

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Sensors and Materials, Vol. 36, No. 8 (2024)

in low dimensions. Graphene, in particular, is a material that is expected to become a beyondCMOS material, and there are reports of field-effect transistors fabricated from graphene.(3–5)
However, it is difficult to modulate its electronic structure and express functionality by carrier
doping as freely as in semiconductor devices. Particularly in silicon-based semiconductors,
where purity can be guaranteed down to eleven nine (11N), carrier concentration control andband structure control work very effectively. In compound semiconductors, the band structure
can be controlled by crystal growth using artificial lattices and thin-film growth, which hasenabled the development of high-frequency devices such as high-electron- mobility transistors.(6)On the other hand, silicon-based semiconductors are very important devices in terms of bothcost and process, but the limits of device performance due to advances in microfabrication andthe band structure itself are becoming apparent. Therefore, in SiGe-based semiconductor
devices,(7) a band modulation mechanism based on lattice distortion has been introduced toachieve high carrier mobility. This active use of lattice distortion has the potential not only tomodulate the band structure of known material systems, but also to express new functionalities,
and the smallest mutation in nanospace has the potential to alter the properties of the entire
material system on a macroscopic scale.(8–13)
For example, elastic modulus is treated as a well-known material constant on a macroscopic
level, but from a microscopic view point, it is expressed by crystal lattice and electron
correlation.(8–19) For example, the elemental substitution or application of external stress induces
band modulation, which changes the physical properties of materials, and this physical propertychange has been studied by various methods to pursue scientific theories. For example, rareearth compounds including Ce exhibit a transition to superconductivity at low temperatures
when pressure is applied.(20,21) This phenomenon is caused by the modulation of electronic
correlations on the nano- and microscales by macroscopic pressure effects, and has beenclarified by precisely measuring macroscopic response characteristics with high sensitivity
using the de Haas–van Alphen and magnetoresistance effects, which directly enable us toobserve the Fermi surface.(20,21) The theoretical description of the microscopic picture using
physical models has revealed various physical symmetries and origins behind the phenomenon,
leading to the rediscovery of two-dimensional materials such as graphene.(8,9)
In fact, the mechanisms of adhesion, friction, rubbing, degradation, destruction, cohesion,and dispersion are not well understood. This is because the physical and chemical phenomena atinterfaces and surfaces are occured at the boundaries between different materials. Interfaces andsurfaces are often ignored in the bulk. However, in nanoscale and microscale materials anddevices, the effects of interfaces and surfaces are more pronounced.(10,22–24) Nanoscale materials
are all around us if we are aware of them. For example, the permanent magnet materials used in
motors and generators are made of sintered nano/microparticles, and recent studies have shownthat the magnetic properties of the nano/microparticles themselves and the composition ofelements and structures at their grain boundaries determine their magnetic properties. In
addition, gold colloids are used for stained glass because their color changes with the particle
size, and by modifying their surfaces with antibodies, they are used as a labeling and display
mechanism in immunochromatography, and are widely used in medical settings as kits fortesting for infectious diseases.(25,26) Antigen–antibody reactions are chemical bonding reactions
at the interface, with liquid as the surrounding environment. The mechanism of action and theSensors and Materials, Vol. 36, No. 8 (2024)

3467

electronic state at such sites are still largely unknown.
In view of the above, it is essential to elucidate the governing factors and mechanisms ofaction of nano- and microscale mechanical properties in order to understand the fundamental
physical and chemical mechanisms. For this purpose, a system that can measure electronic states
and chemical bonding at surfaces and interfaces while controlling mechanical specifics in a
microregion is demanded.(23,24)
Therefore, in this study, we focused on micro electro mechanical systems (MEMS) devices,
whose mechanical behavior can be controlled by electrical stimuli and vice versa.(16,17,27–30)
Synchrotron radiation analysis is a very powerful analytical tool, but especially for soft X-ray
analysis, devices must be manipulated in vacuum, and it is difficult to introduce ordinary
mechanical tensile testing machines and actuators into a vacuum chamber. Therefore, as
schematically illustrated in Fig. 1(a), we will construct an experimental system to perform
synchrotron radiation analysis and micro-Raman spectroscopy measurements using MEMS
devices.

2.

Experimental Procedure

MEMS design was conducted to realize MEMS devices for in-plane three-point tensile test
and out-of-plane bending deformation, schematically illustrated in Fig. 2 and Fig. 3, respectively.

(a)

(b)

Fig. 1. (Color online) (a) Schematic of synchrotron radiation analysis and Raman spectroscopy for a sample
strained by using MEMS device. (b) Layout of MEMS device on silicon wafer generated from CAD data.

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Sensors and Materials, Vol. 36, No. 8 (2024)

Cross section
Bottom electrodeHole diameter : 480 μm

Upper electrode 1
Cross section
tensile distortion

Si beam

Raman measurement area

Upper electrode 2

Upper electrode (Ti/Pt)

PZT

Thin Si beamSi
substrate

Upper electrode 3

Sisubstrate
Bottom electrode (Ti/Pt)

Si beam：thickness 5μm
2 × 2 mm2

Si substrate thickness：530 μm

Fig. 2. (Color online) Overview of a three-point tensile test MEMS device. The substrate size is 2 × 2 mm2. The
three-point tensile test mechanism structure is located at the center. The silicon island at the center is strained by
PZT in three directions and subjected to tensile or compressive stress. A schematic of the MEMS cross-sectional
shape is shown in the inset.

Cross section
Double-sided folded beam
Cross section

Upper electrode (Ti/Pt)

PZT

Thin Si beamSi
substrate

Si
substrate
Bottom electrode (Ti/Pt)

Bottom electrodeSi substrate thickness：530 μm

Upper electrodeSi beam：thickness 5μm
2 × 2 mm2

Fig. 3. (Color online) Overview of a MEMS device with a double-sided beam structure. The substrate size is 2 × 2mm 2. Multiple double-sided beams are arranged in a row, and when voltage is applied to the top and bottom
electrodes, the beams bend to enable bending tests. A schematic of the MEMS cross-sectional shape with respect tothe beam structure is shown in the inset.

Sensors and Materials, Vol. 36, No. 8 (2024)

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Originally, an electrostatic actuator structure was frequently used, but a prototype was developed
to determine whether an in-plane three-point tensile test structure based on an out-of-planebending deformation element structure using lead zirconate titanate, Pb(Zr, Ti)O3 (PZT), would
be possible. There are two reasons: One is that there was an experimental report indicating thatthe electronic state of graphene can be significantly modulated by in-plane three-point tensile,(8,9)
so we considered a device structure that can perform the in-plane three-point tensile test with a
MEMS structure. The other was to fabricate the in-plane three-point tensile test device at thesame time as a MEMS with a cantilever structure using PZT, which has been proven to be a
driving source, in order to improve the efficiency of the process and device fabrication.
Piezoelectric analysis (static analysis) was performed on the two designed device structuresusing a MEMS simulator, FEMTET.(31) The piezoelectric layer was divided into two layers witha mesh size of 5 μm. The lower electrode of the piezoelectric layer was set as GND and voltage
was applied to the upper electrode. The aim of this study was to perform an in-plane tensilecompression test of the center using out-of-plane bending deformation with PZT. As shown in
(a)

4.0
3.0
2.0

Raman measurement/imaging area

1.0
0.0

X’
100

0

X

200

300

400

X’

Distortion distributionX
Z (nm)
160
110
75
24

Displacement along z-axis

-10

(b)
1.0

X’

0.8
0.6
0.4
0.2

0

X

100

200

300

400

500

X’

PEEM measurement area

X

Fig. 4. (Color online) Simulation results of strain evaluation for MEMS and optical photographs of prepared
MEMS devices: (a) three-point tensile test type and (b) double-sided beam structure type. The spatial variation of
distortion along the positions X – X’ is shown in each graph.

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Sensors and Materials, Vol. 36, No. 8 (2024)

Fig. 4(a), the simulation results show that the center of the in-plane three-point tensile device hasan almost constant height in the Z-direction, but the strain distribution spreads isotropicallyfrom the center with a spatial gradient in the in-plane direction. On the other hand, as an out-ofplane bending deformation element using PZT, simulation evaluation was also conducted for a
double-sided symmetric folded-beam structure element. The results are shown in Fig. 4(b). As
expected, the strain distributions related to out-of-plane bending deformation were obtained forthe cantilever beam structure element. The same fabrication process was used to fabricate bothdevices by changing the lithography patterns.
MEMS devices that realize the three-point tensile test and double-sided symmetric foldedbeam structures are prepared on a silicon substrate. Figure 1(b) shows a conceptual diagram ofthe structure of these MEMS devices exploited from the actual CAD data. The MEMS elements
to be fabricated are 2 × 2 mm2 in size and were constructed using multiple simultaneous
semiconductor processes on a wafer. Figure 2 shows the structure of the MEMS device for thethree-point tensile test. The beam structure with a thickness of 5 μm was configured at 120°, andthin film fabrication was performed on it using a sputtering system in the following
configuration: bottom electrode (Ti/Pt)/thin PZT film/top electrode (Ti/Pt)/polyimide protective
layer. The details of the fabrication procedure are described in Refs. 27–30. By applying voltage
to the top and bottom electrodes (GND), a three-point tensile test can be performed. A schematicof the cross section near the center of the hole is shown in Fig. 2.
Similarly, a MEMS device with a double-sided symmetric folded-beam structure wasconstructed by changing the pattern using the same process. Figure 3 shows a schematic
diagram. The device size is also 2 × 2 mm2, with a beam structure of 5 μm thickness. Thin films
were fabricated using a sputtering system, consisting of a bottom electrode, a PZT thin film, top
electrode, and a polyimide protective film on top of the beam structure. By applying electricalpressure to the top and bottom electrodes, the PZT develops a piezoelectric effect, causing thebeam structure to rise and fall while flexing.(27–30) Both optical photographs of the actual
MEMS devices fabricated are shown in Figs. 4(a) and 4(b), respectively.
The purpose of this study is to confirm whether MEMS devices can be incorporated into
synchrotron radiation analysis and micro-Raman spectroscopy systems. For the micro-Raman
spectroscopy system, the three-point tensile-type MEMS device was fixed under the lens toprevent it from moving. As schematically illustrated in the inset of Fig. 5(a), the device was set
and Raman spectra were measured at the center of the triangle beams. In particular, we will
implement the device in an X-ray magnetic circular dichroism (XMCD) photoelectron emission
microscopy (PEEM) system using a synchrotron radiation analysis system at BL17SU in
SPring-8. Since the PEEM using soft X-rays also needs to operate in an ultrahigh-vacuum(UHV) apparatus, we will determine whether the MEMS devices can operate by introducing
them into the system in which we have been conducting RF application and heating
experiments.(32–35) In other words, a mechanical strain application mechanism using MEMS will
be introduced as a novel experimental mechanism to the synchrotron radiation photoelectron
spectroscopy microscopy system, which has an operando experimental environmental and isequipped with current and voltage application mechanisms.

Sensors and Materials, Vol. 36, No. 8 (2024)

3471

514 cm -1

(a)

(b)
!"#

460

480

500 520 540 560
Raman shift (cm -1)

580! " # "intensity$%&$' ( $) &' *%+" , - .%/ unit)
$&' 0
Raman
(arb.

! " # "intensity$%&$' ( $) &' *%+" , - .%/ unit)
$&' 0
Raman
(arb.

Lens
×50

600

490

521 cm -1

+7 V
0V
-7V

500

510

520

530

540

Raman shift (cm -1)

Fig. 5. (Color online) Raman spectra at the central Si island of a three-point tensile test-type MEMS device. (a)Raman spectra measurement results over a wide range when electric voltages of +7, 0, and −7V were applied. (b)Raman spectra with extended Raman spectra shown in (a). The device and Raman spectroscopy arrangements areschematically shown in the inset.

3.

Results and Discussion

Before these operando experiments and analyses, we confirmed the operation of the MEMS
device by introducing it into the micro-Raman spectrometer. First, to confirm the drive of the
MEMS device by the Raman microscope, we determined whether the Raman shift caused by the
distortion of the silicon beams could be observed or not. The center of the MEMS device for thethree-point tensile test has an exposed silicon surface as shown in Fig. 4(a). The Raman spectrum
was measured by focusing the objective lens (×50) of the microscopic Raman spectrometer at thecenter of three-point tensile devices illustrated schematically in Fig. 4(a). The measurement
results are shown in Fig. 5. In the absence of strain in the crystal, the optical mode of Si (F2gmode) is triple degenerate with Raman activity, and only one Raman band is observed at
520 cm−1.(36–39) Upon the application of uniaxial or biaxial stress, the triple degenerate modes aredegenerate and split into singlet and doublet modes. In a backscattering configuration, only the
LO mode, in which the atoms mutate in the <001> direction, is observed. That is, only the singlet
mode corresponds to the mode observed at 514 cm−1. When the strain ε is applied, thewavenumber shift Δω for each Raman mode is known to be proportional to the strain. (36–39)∆ω = ω − ω0 = bε ,(1)where ω and ω0 are the Raman wavenumber obtained when the strain is applied and the original
Raman wavenumber obtained in the absence of strain, respectively. The proportionality
coefficient b for the LO mode is reported to be b ~723 ± 15 cm–1. Given a strain of 1 × 10 –4, awavenumber change of about 0.7 cm–1 should be obtained. With the device design used in this

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Sensors and Materials, Vol. 36, No. 8 (2024)

study, it is possible to give a strain of 1 × 10 –4, as shown in Figs. 2 and 3, but it is difficult to
detect this wavenumber shift because the wavenumber resolution of the Raman spectrometer is a
few cm–1. However, since the spectral measurement is performed and the waveform changes in
response to the MEMS device driven, it can be inferred that the Raman shift is caused by theadded distortion. Originally, since distortion is added when the device is fabricated, a Raman
band of 521 cm–1 without distortion and a Raman band of 514 cm–1 corresponding to the LOmode are detectable. Therefore, we will confirm that this system and the R&D direction aresuitable for our purpose by observing how much the intensity ratio of the two changes when thedevice is driven.
As for the excitation laser wavelength and penetration depth, the wavelength of the laser
source in our micro-Raman spectrometer was 785 nm, so the penetration depth into crystalline
Si is considered to be about 10 μm. In this case, the thickness of the Si beam structure is 5 μm, so
we can assume that we are observing the stress of the entire beam structure. On the other hand,when compressive stress is applied, the Raman lines shift to the high-wavenumber side. In Fig.
5, two Raman lines at 514 and 521 cm−1 are detected. The difference in Raman intensity between
them indicates that tensile stress is applied. Figure 5(a) shows that there are only the earlier two
Raman lines even when the measurement area is expanded. To measure the Raman spectralchange in detail when voltage is applied to the MEMS device, the measurement area is expanded
and the dependence of the Raman spectra on the application of voltage is compared in Fig. 5(b).
In Fig. 5(b), it is clear that when voltage is applied to the MEMS device, the Raman lines shiftslightly, but intensity changes occur. For each Raman shift, the voltage dependence of theintensity is shown in Fig. 6(a): the peak intensity at 521 cm−1 is almost independent of voltage,
while the peak intensity at 514 cm−1 shows voltage dependence. To illustrate this point, the(b) 0.960

(a)

0.955

RRatio = R521 / R514 (arb. unit)

Raman intensity (arb. unit)

514 cm -1

521 cm -1

-10

-5

0
Voltage (V)

5

10

0.950

0.945
0.940
0.935
0.930
-10

-5

0

5

10

Voltage (V)Fig. 6. (Color online) (a) Electric voltage dependences of Raman intensities at 514 and 521 cm−1. (b) Raman
intensity ratio is defined as Rr = R521/R514, where R521 and R514 are the Raman intensities at 521 and 514 cm−1,
respectively.

Sensors and Materials, Vol. 36, No. 8 (2024)

3473

voltage dependence of the Raman peak intensity, Rratio = R521/R514, is shown in Fig. 6(b). It isfound that the Raman intensity ratio increases with voltage when a positive voltage is applied.
Next, micro-Raman mapping was performed on the observed area, a 30 × 30 μm 2 region witha 1 μm step. Figures 7(a) and 7(b) show the peak mappings at 514 and 521 cm−1, respectively. It
can be seen that the spatial distribution of the Raman peak intensity changes with the applicationof voltage. This indicates that there is stress distribution within the silicon beam due to tensilestress caused by MEMS. In other words, the stress distribution is not uniform, indicating that
there are local fluctuations. Probably, the origin is the spatial distribution of local strain during
the device fabrication, i.e., the microfabrication and deposition of PZT and other films. After thedevice fabrication is finished, distortion due to its own weight and vibration during transportation
may also generate strain distribution, although it is a very delicate structure.
From the above, it was found that tensile stress can be controlled by MEMS devices.
Therefore, a basic experiment was conducted to introduce MEMS devices into a soft X-ray
PEEM system. The experiment was conducted in the PEEM apparatus installed at BL17SU in
SPring-8. In our previous studies,(32–35) a current electrode terminal for introducing microwaves
was installed in this apparatus to directly observe the vortex swirling behavior of magnetic
disks. In this study, we connected a MEMS device to this current electrode terminal to determine
whether the MEMS device can operate in the UHV environmental state. Figure 8(a) shows aschematic setup of the MEMS device in the PEEM system with electrodes wired to the powersource. Figure 8(b) shows an optical photograph of the MEMS element after it was wired to thesample holder of the PEEM apparatus with a double-sided beam-structure-type MEMS device.
(i)

(i)

(b) 521 cm -1

+5 V

(ii)

+5 V (ii)

0V

0V

-5 V

(iii)

(iii)

-5 V

Raman intensity (arb. unit)(a) 514 cm -1

500

0

30 μm

30 μm
Fig. 7. (Color online) Spatial distribution mappings of Raman peaks at (a) 514 and (b) 521 cm−1 when the electric
voltages of (i) +5, (ii) 0, and (iii) −5 V were applied.

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Sensors and Materials, Vol. 36, No. 8 (2024)

(b)

(a)

(c)

Magnified Image
ScreenProjection Lens

X-raysorHg-light

Aperture

Electrode

870 μmPhotoelectrons

Electrodes

Electrode

Wiring connection with silver paste and tungsten wire

SampleFig. 8. (Color online) (a) Schematic of device arrangement and PEEM observation setup. (b) Optical image of adouble-sided beam-structure-type MEMS device after it is mounted in a PEEM holder at BL17SU in SPring-8. (c)PEEM observation image of a double-sided beam.

The center of the MEMS device has a double-sided beam structure, and the actual PEEM
observation results at a low magnification are shown in Fig. 8(c). Next, Fig. 9(a) shows the PEEM
observation image when a DC voltage of −5 V is applied to the double-sided beam structuretype MEMS device. The near-center position of the detector at which the PEEM image can befocused and observed clearly is read from the device settings. From the positional relationshipbetween the detector and the sample surface, the displacement of the MEMS element due tobending stress is investigated. The distance between the detector and the sample surface isdetermined to be 1.84 mm when the detector is focused as shown in Fig. 9(a). Next, when thevoltage is changed to 0 V, the focus is displaced. Figure 9(b) shows the PEEM observation image
obtained before focusing when the voltage is set to 0 V. Comparing Fig. 9(a) with Fig. 9(b), we
found that the focus was clearly shifted. The out-of-focus observation image was refocused bycontrolling the distance between the detector and the sample surface so that the PEEM
observation image became clear again; the detector position when the PEEM observation image
was in focus was read as 1.93 mm. This process was performed while varying the voltage
applied to the MEMS device, and the voltage dependence of the distance between the sample
surface and the detector is shown in Fig. 9(c). The voltage dependence of the distance between
the sample surface and the PEEM detector indicates that there is some hysteresis when a positive
voltage is applied. However, the results show that the bending displacement of the MEMS
device’s cantilever beam changes almost linearly, indicating that the displacement of about
200 μm can be controlled when the voltage is increased from −5 to +5 V. The above results showthat the MEMS device works as expected in the UHV environmental experimental state.
By using MEMS devices, we found that PEEM observation and micro-Raman spectroscopic
mapping can be performed while conducting tensile stress tests, even with small sample sizes.
The system can be operated in vacuum and can be applied to synchrotron radiation analysis
using soft X-rays. Using this system, we were able to construct an environment in which theSensors and Materials, Vol. 36, No. 8 (2024)(a) DC: -5V(b) DC: 0V

3475

(c)
Sample distance (mm)2.05Sample distance: 1.84 mm

Sample distance: 1.93 mm

2.00
1.95
1.90
1.85
-4

-2

0

2

4

DC voltage (V)Fig. 9. (Color online) PEEM observation of a single beam of a double-sided beam-structure-type MEMS device.
(a) PEEM image of the single beam when focusing at an electric voltage of −5 V applied to the MEMS device. The
distance between the sample surface and the PEEM detector was 1.84 mm. (b) PEEM image when the electric
voltage was set to 0 V. The image is not focused at this time and is unclear. The distance between the sample surface
and the PEEM detector was adjusted to obtain a clear PEEM image. Then, the distance was 1.93 mm. The distancewhen the electric voltage was applied to the MEMS device was changed by repeating this operation. By measuring
this distance, the operating range of the beam when the electric voltage is applied to the MEMS device can be
examined. The data obtained in this way are summarized in (c), indicating the electric voltage dependence of the
distance.

electronic and chemical states of a sample mounted on a MEMS device or an adhesive interface
can be directly measured while mechanically modulating the state of the sample.

4.

Conclusion

To investigate the chemical and electronic states of a sample when mechanical strain isapplied, basic introduction experiments were conducted on the electrically controlled mechanicalstress application mechanism using MEMS devices. We succeeded in introducing a three-point
tensile MEMS device and a double-sided beam structure MEMS device, both of which are
driven by PZT. In combination with micro-Raman spectroscopy, we succeeded in detecting theRaman signal change by tensile testing in the region where the silicon beams of the MEMS
device were exposed. We also succeeded in introducing the MEMS device into an ultrahighvacuum chamber and demonstrated that the system can be combined with PEEM observation.
This system is expected to provide a procedure to quantitatively and systematically evaluatemechanical stress changes in chemical and electronic states in the adhesive region, as well as
chemical state changes in polymer materials and other materials due to the application of stress.

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Sensors and Materials, Vol. 36, No. 8 (2024)

Acknowledgments
The experiments at BL17SU in SPring-8 were performed with the approval of JASRI(Proposal Nos. 2021B1171 and 2021A1414) and RIKEN (Proposal Nos. 20200081, 20210016,
20220084, and 20230020). This work was partially supported by Futaba Foundation, Amano
Institute of Technology, and the Hyogo Science and Technology Association.

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