研究者詳細 - 石丸　学

論文 - 石丸　学

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Explosive crystallization of sputter-deposited amorphous germanium films by irradiation with an electron beam of SEM-level energies 査読有り

Nakamura R., Matsumoto A., Ishimaru M.

Journal of Applied Physics 129 ( 21 ) 2021年06月

記述言語：英語掲載種別：研究論文（学術雑誌）

The crystallization of sputter-deposited substrate-free films of amorphous germanium was induced by electron irradiation at SEM-level energies of less than 20 keV at ambient temperature using an electron probe microanalyzer. Instantaneous crystallization, referred to as explosive crystallization, occurred consistently at 2-20 keV; the threshold of electron fluxes is 1015-1016 m−2 s−1, which is five to six orders of magnitude lower than those at 100 keV reported previously. This process is expected to be advantageous in the production of polycrystalline Ge films since it is rapid, requires little energy, and results in negligible damage to the substrate.

DOI： 10.1063/5.0052142

Kyutacar

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Nanostructures and flux pinning properties in YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7- y </inf>thin films with double perovskite Ba<inf>2</inf>LuNbO<inf>6</inf>nanorods 査読有り

Gondo M., Yoshida M., Yoshida Y., Ishimaru M., Horide T., Matsumoto K., Kita R.

Journal of Applied Physics 129 ( 19 ) 2021年05月

記述言語：英語掲載種別：研究論文（学術雑誌）

Double perovskite Ba2LuNbO6 (BLNO)-doped YBa2Cu3O7-y (YBCO) thin films are fabricated on a SrTiO3 (001) substrate by pulsed laser deposition, and their nanostructures are characterized by transmission electron microscopy and scanning transmission electron microscopy. Cross-sectional observations and elemental mapping reveal that BLNO self-assembles during thin film deposition, and consequently, nanorods extending straight from the substrate to the surface are formed in the YBCO thin films. It is confirmed that stacking faults perpendicular to the growth direction disturb the formation of BLNO nanorods. Strain maps extracted by geometric phase analysis reveal that the tensile strain occurs in the YBCO matrix around the BLNO nanorods. Misfit dislocations are periodically introduced at the interface between the nanorod and the matrix, which results in the inhomogeneous strain of YBCO around the BLNO nanorods. The superconducting properties of the YBCO + BLNO thin films are compared with those of other previously reported YBCO thin films with normal perovskite and double perovskite nanorods.

DOI： 10.1063/5.0048693

Kyutacar

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Enhancement of Thermoelectric Properties of n-Type Bi<inf>2</inf>Te<inf>3- x</inf>Se<inf>x</inf>by Energy Filtering Effect 査読有り

Kawajiri Y., Tanusilp S.A., Kumagai M., Ishimaru M., Ohishi Y., Tanaka J., Kurosaki K.

ACS Applied Energy Materials 4 ( 10 ) 11819 - 11826 2021年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

A pair of n-type Bi2Te3-xSex and p-type (Bi,Sb)2Te3 is known as a promising candidate for assembling a high thermoelectric efficiency module operating at near room temperature. While the dimensionless figure of merit (zT) of p-type (Bi,Sb)2Te3 is commonly larger than 1.0, n-type Bi2Te3-xSex has a lower zT value of μ0.8 at room temperature. Here, we aim to enhance the zT of n-type Bi2Te3-xSex through the energy filtering effect that can improve the Seebeck coefficient by adding Au. In the Bi2Te2.8Se0.2 + 5 at % Au composite, the Seebeck coefficient is significantly improved, and the electrical resistivity does not change significantly, leading to an approximately twice as high power factor as that of the non-Au-added one at near room temperature. Also, the addition of Au suppresses the thermal conductivity. These advantages result in a maximum zT of over 1.0 at room temperature and average zT value of 1.05 at T = 300-400 K, an μ75% improvement, which is comparable to those of the reported n-type Bi2Te3-based materials. Also, Au addition shows no negative effect on the mechanical properties as well as high-temperature stability of Bi2Te3-xSex. These results indicate that Au addition is a promising method to improve the thermoelectric properties of n-type Bi2Te3-xSex used for assembling a practical thermoelectric module operating at near room temperature.

DOI： 10.1021/acsaem.1c02560

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Structure analysis of Hf<inf>0.5</inf>Zr<inf>0.5</inf>O<inf>2</inf> thin films crystallized from amorphous phase by thermal annealing below 500°C 査読有り

Fujio R., Ishimaru M., Migita S., Uchida N.

2021 Silicon Nanoelectronics Workshop, SNW 2021 2021年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Hf0.5Zr0.5O2, (HZO) films are anticipated as a noval insulating material for ferroelectric field-effect transistors. These materials are fabricated by crystallization of amorphous HZO, and therefore knowledge of crystallization processes is required. We examined thermally-induced crystallization processes of amorphous HZO prepared by sputtering using x-ray diffraction and transmission electron microscopy. It was found that a metastable orthorhombic phase is formed in 10 nm thick HZO films after thermal annealing at 500°C.

DOI： 10.1109/SNW51795.2021.00018

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アモルファスGeSnの結晶化におけるSnの振る舞い招待有り査読有り

石丸　学, 仲村龍介

まてりあ 59 ( 12 ) 662 - 668 2020年12月

Combined effect of nanorod and stacking fault for improving nanorod interface in YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7-δ</inf>nanocomposite films 査読有り

Horide T., Ishimaru M., Sato K., Matsumoto K.

Superconductor Science and Technology 33 ( 11 ) 2020年11月

記述言語：英語掲載種別：研究論文（学術雑誌）

Self-organized nanorods in YBa2Cu3O7-δ films are important pinning centers from the technical and fundamental views. While influence of nanoscale factors (>4-5 nm) on the vortex pinning has already been discussed in detail, the interface control of nanorods (at the smaller scale) has not yet been performed. Here, it is demonstrated that the stacking faults can control the nanorod interface to improve the vortex pinning. The stacking faults were formed across the nanorods by post-annealing the YBa2Cu3O7-δ films containing BaMO3 (M = Zr, Sn, Hf) nanorods. The strong bonding between YBa2Cu3O7-δ and BaMO3 varies the atomic position of YBa2Cu3O7-δ, degrading an interface sharpness and an elementary pinning force of the nanorod. Scanning transmission electron microscopy and density functional theory calculation clarified that the stacking faults broke the strong bonding between YBa2Cu3O7-δ and BaMO3 at the nanorod interface, and reduced the local strain around the nanorods, improving the elementary pinning force. As a result, the critical current density was improved in low temperature and low magnetic field when magnetic field was aligned with the c-axis. Thus, the combined effect of nanoinclusions and crystalline defects, in the present case, nanorods and stacking faults, can control the interface of nanoinclusion pinning centers, opening the interface design to realize the ideal pinning situation.

DOI： 10.1088/1361-6668/abaebf

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Dual-Beam Irradiation Stability of Amorphous Silicon Oxycarbide at 300°C and 500°C 査読有り

Su Q., Greaves G., Donnelly S.E., Mizuguchi S., Ishimaru M., Nastasi M.

JOM 72 ( 11 ) 4002 - 4007 2020年11月

記述言語：英語掲載種別：研究論文（学術雑誌）

The irradiation stability of a material in the temperature range from 300°C to 500°C represents an important step for a variety of nuclear applications. Here we used dual-beam irradiation to investigate the response of an amorphous silicon oxycarbide (SiOC) to extreme environments (temperature and irradiation). The amorphous SiOC was prepared in thin film form by sputtering and then fabricated into cross-sectional transmission electron microscopy (TEM) specimens, and finally irradiated with helium (He) and krypton (Kr) ions inside a TEM. In-situ TEM observations revealed that He bubble and void formation are highly suppressed after irradiation up to 95 dpa with simultaneous He implantation up to 231 at.%. Atomic pair-distribution functions suggested that the amorphous structures are almost the same before and after irradiation, and no crystallization, nor phase separation was detected. This study demonstrates the stability of amorphous SiOC under dual-beam irradiation at nuclear reactor operation temperatures, suggesting that this material is applicable as a structural material for advanced nuclear reactors.

DOI： 10.1007/s11837-020-04332-z

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Simultaneous achievement of high J <inf>c</inf>and suppressed J <inf>c</inf>anisotropy by hybrid pinning in YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7</inf>three-phase-nanocomposite film 査読有り

Horide T., Torigoe K., Ishimaru M., Kita R., Awaji S., Matsumoto K.

Superconductor Science and Technology 33 ( 10 ) 2020年10月

記述言語：英語掲載種別：研究論文（学術雑誌）

Nanoscale pinning centers are introduced into YBa2Cu3O7 (YBCO) films and tapes to improve vortex pinning and critical current density (J c) for coated conductor application. While pinning with a single type of pinning center has been mainly investigated, hybrid pinning with multiple types of pinning center is expected to be more promising for simultaneously achieving high J c values and suppressing J c anisotropy. In the present study, a three-phase-nanocomposite film consisting of an YBCO matrix, BaHfO3 nanorods and Y-O nanoparticles was fabricated. A global pinning force maximum (F p,max, where F p = J c B) of 1.57 TN m-3 at 4.2 K, which is as high as the record level of F p,max, was achieved by the hybrid pinning of BaHfO3 nanorods and Y-O nanoparticles. Furthermore, the hybrid pinning improved the angular dependence of J c. The pinning contribution from nanoparticles increased with lowering temperature, which can explain the high J c at low temperature. Thus, the present study successfully demonstrates a highly effective structure that can simultaneously achieve suppressed J c anisotropy and a record level of J c.

DOI： 10.1088/1361-6668/aba544

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Dual crystallization modes of sputter-deposited amorphous SiGe films 査読有り

Okugawa M., Nakamura R., Numakura H., Ishimaru M., Yasuda H.

Journal of Applied Physics 128 ( 1 ) 2020年07月

記述言語：英語掲載種別：研究論文（学術雑誌）

The crystallization behavior of sputter-deposited films of amorphous Si (a-Si) and SiGe alloys (a-SiGe) induced by electron irradiation at room temperature and by thermal annealing was investigated by in situ transmission electron microscopy. On electron irradiation at room temperature, extremely rapid crystallization, so-called explosive crystallization, occurred at a higher electron flux but not at a lower electron flux. On in situ thermal annealing, explosive crystallization occurred preferentially and partially at low temperatures in Ge-rich a-SixGe100-x for x < 50 but not for x > 50. These results indicate that the increase of Si content in a-SiGe prevents the occurrence of explosive crystallization. We previously proposed that explosive crystallization can occur in pristine a-Ge films via the interface of a liquid-like, high-density amorphous state at the growth front. An increase in the instability of this high-density amorphous state caused by the increase of Si in a-SiGe apparently gives rise to the suppression of explosive crystallization.

DOI： 10.1063/5.0010202

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Effects of hydrogen on structure and crystallization behavior of sputter-deposited amorphous germanium films 査読有り

Hanya Y., Nakamura R., Okugawa M., Ishimaru M., Oohata G., Yasuda H.

Japanese Journal of Applied Physics 59 ( 7 ) 2020年07月

記述言語：英語掲載種別：研究論文（学術雑誌）

We examined by transmission electron microscopy the structure and crystallization behavior of hydrogenerated and non-hydrogenerated amorphous germanium films (a-Ge:H and a-Ge) prepared by sputtering to figure out the effects of hydrogen on them. In pair-distribution function, first and second peaks at the interatomic distance of 0.26 and 0.40 nm, respectively, were found to be higher and sharper in a-Ge:H than in a-Ge; therefore amorphous structure was organized in a more ordered state within a short range by hydrogeneration. On thermal annealing, fine nanograins (FGs) of about 10 nm in size appeared preferentially at 350 °C and above in a-Ge:H, which is in contrast with the formation of coarse particles of about 100 nm in size at 500 °C in a-Ge. Hydrogeneration would make a certain number of short-range ordered clusters distributed in the amorphous matrix, inducing the preferential formation of FGs at lower temperatures.

DOI： 10.35848/1347-4065/ab9cd9

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Liquid-mediated crystallization of amorphous GeSn under electron beam irradiation 査読有り

Inenaga K., Motomura R., Ishimaru M., Nakamura R., Yasuda H.

Journal of Applied Physics 127 ( 20 ) 2020年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

Crystallization processes of amorphous germanium–tin (GeSn) under low-energy electron-beam irradiation were examined using transmission electron microscopy (TEM). Freestanding amorphous GeSn thin films were irradiated with a 100 keV electron beam at room temperature. The amorphous GeSn was athermally crystallized by electron-beam irradiation, when the electron flux exceeded the critical value. Heterogeneous structures consisting of nano- and micro-crystallites were formed after crystallization of amorphous GeSn with ∼24 at. % Sn in the as-sputtered amorphous state. In situ TEM observations of structural changes under electron-beam irradiation revealed that random nucleation and growth of nanocrystallites occur at the early stage of crystallization, followed by rapid formation of micro-grains surrounding the nanocrystals. It has been suggested that the growth of micro-grains progresses via supercooled liquid Sn at the amorphous/crystalline interface. The resultant GeSn grains with a size of a few micrometers contained ∼15 at. % Sn, much larger than the solubility limit of Sn in Ge (∼1 at. % Sn).

DOI： 10.1063/5.0006416

Kyutacar

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Deposition-temperature dependence of vortex pinning property in YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7</inf>+BaHfO<inf>3</inf> films 査読有り

Horide T., Torigoe K., Kita R., Nakamura R., Ishimaru M., Awaji S., Matsumoto K.

Materials Transactions ( 日本金属学会 ) 61 ( 3 ) 449 - 454 2020年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

Improvement of critical current density (Jc) in magnetic fields is required in YBa2Cu3O7 films, and process parameters should be optimized for controlling pinning centers. In the present study, a deposition temperature was varied in pulsed laser deposition of YBa2Cu3O7+BaHfO3 films to control the nanorod structure, and its influence on Jc was analyzed. The YBa2Cu3O7+BaHfO3 film deposited at 850°C exhibited pinning force maximum (Fp,max.) as high as 413GN/m3 at 40 K, while the Fp,max. for the deposition temperature of 850°C at 77K was smaller than that in the YBa2Cu3O7+BaHfO3 film deposited at 900°C. A critical temperature decreased and matching field increased with decreasing the deposition temperature. Increase in deposition temperature is effective in improving the Fp,max. in high temperatures, since the critical temperature and matching field dependences of Jc value dominate the Fp,max. On the other hand, low deposition temperature improves the Fp,max. in low temperatures since the Fp shift in accordance with matching field is dominant to the Fp,max. Thus, the deposition temperature should be set in pulsed laser deposition of YBa2Cu3O7 films containing nanorods considering the Jc variation with critical temperature and matching field.

DOI： 10.2320/matertrans.MT-M2019303

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Carrier and heat transport properties of poly-crystalline GeSn films for thin-film transistor applications 査読有り

Uchida N., Hattori J., Lieten R., Ohishi Y., Takase R., Ishimaru M., Fukuda K., Maeda T., Locquet J.

Journal of Applied Physics 126 ( 14 ) 2019年10月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 Author(s). Thin-film transistors (TFTs) on insulator substrates are widely used in applications from liquid crystal displays to sensor devices. However, insulator substrates with low heat conductivity lead to unfavorable self-heating effects in the channel regions. Herein, the carrier and heat transport properties of polycrystalline GeSn films on SiO2/Si substrates were improved by suppressing Sn segregation in the films to fabricate GeSn channel TFTs. Alloying with 5.5% Sn enabled the formation of larger grains than those in poly-Ge films after low-temperature annealing (below 520 °C) without Sn segregation. In addition, the films had a hole mobility of 40 cm2 V-1 s-1 at a hole density of 1.1 × 1018 cm-3 and a thermal conductivity of 12.1 Wm-1 K-1 at room temperature. The temperature dependences of the carrier and heat transport properties of the poly-GeSn films were investigated to accurately simulate a device with a poly-GeSn channel TFT. This was achieved by using the carrier transport measurements and numerical simulations of the heat transport in the Debye model. The simulated device allowed an accurate assessment of the self-heating effects of the TFT and thus provides a design guide for TFTs.

DOI： 10.1063/1.5085470

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Thermoelectric Property in Orthorhombic-Domained SnSe Film 査読有り

Horide T., Murakami Y., Hirayama Y., Ishimaru M., Matsumoto K.

ACS Applied Materials and Interfaces 11 ( 30 ) 27057 - 27063 2019年07月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 American Chemical Society. Single-crystal SnSe exhibits extremely high thermoelectric properties, and fabrication of SnSe films is promising for practical application and basic research on properties. However, the high thermoelectric properties have not yet been reported in SnSe films and their thermoelectric properties and nanostructure have not yet been analyzed in detail. In the present study, a-axis-oriented epitaxial SnSe films were prepared to discuss the thermoelectric properties of the SnSe films. While the electrical conductivity of the films was orders of magnitude smaller than that in the single crystals at room temperature, surprisingly, the thermoelectric property (power factor) of the films was slightly higher than that in the single crystals at high temperatures (∼300 °C). The SnSe films contained orthorhombic domain boundaries with a spacing of several hundred nanometers. The orthorhombic domain boundaries caused carrier scattering and degraded the mobility of the films at room temperature, but their effect decreased with increasing temperature. Thus, the carrier scattering at domain boundaries results in characteristic temperature dependence of thermoelectric properties in the SnSe films. High thermoelectric properties at high temperatures were successfully achieved in the SnSe films in spite of the existence of domain boundaries, demonstrating the possibility of high-performance of SnSe thermoelectric films.

DOI： 10.1021/acsami.9b04868

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Observation of inhomogeneous depinning in YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7</inf> composite multilayers 査読有り

Horide T., Ishimaru M., Matsumoto K.

Superconductor Science and Technology 32 ( 8 ) 2019年06月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 IOP Publishing Ltd. Composite multilayer films (CMLs) comprising YBa2Cu3O7 + BaHfO3 (4.7 vol%)/YBa2Cu3O7 + BaHfO3 (3.1 vol%) were fabricated, and vortex behavior in the CMLs was evaluated to discuss inhomogeneous depinning of vortices. Magnetic field and angular dependences of critical current density (J c) in the CMLs were similar to those in the YBa2Cu3O7 + BaHfO3 (4.7 vol%) single layer film (SL). Variation of the CML structure shifted the matching field effect in global pinning force and irreversibility temperature. The J c in the YBa2Cu3O7 + BaHfO3 (4.7 vol%) SL was smaller than that in the YBa2Cu3O7 + BaHfO3 (3.1 vol%) SL, suggesting that vortices preferentially moved along the low-J c layers in the CMLs. The high-J c layers pinned the vortices in the low-J c layers, resulting in a shift of the matching field effect. These observations are characteristic of inhomogeneous depinning of vortices in the CMLs. The inhomogeneous depinning as well as pinned configuration should be considered for understanding J c and for structural design of pinning centers in YBa2Cu3O7 films.

DOI： 10.1088/1361-6668/ab1d2c

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Direct observations of crystallization processes of amorphous GeSn during thermal annealing: A temperature window for suppressing Sn segregation 査読有り

Higashiyama M., Ishimaru M., Okugawa M., Nakamura R.

Journal of Applied Physics 125 ( 17 ) 2019年05月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 Author(s). The solubility limit of tin (Sn) in germanium (Ge) is very small, and, therefore, it is difficult to synthesize high Sn concentration GeSn crystals by conventional methods. An amorphous phase can contain elements beyond the solubility limit of the crystal state, and, therefore, recrystallization of the amorphous alloy is one of the possible ways to realize materials far from the equilibrium state. To suppress Sn precipitation during thermal annealing, knowledge of crystallization processes is required. In the present study, amorphous GeSn thin films with different Sn concentrations were prepared by sputtering, and their crystallization processes were examined by in situ transmission electron microscopy. It was found that the crystallization temperature decreases with increasing Sn concentration, and it became lower than the eutectic temperature when the Sn concentration exceeded ∼25 at. %. Radial distribution function analyses revealed that phase decomposition occurs in the amorphous state of the specimens which crystallize below the eutectic temperature, and Sn crystallites were simultaneously precipitated with crystallization. On the other hand, no remarkable phase decomposition was detected in amorphous GeSn with <25 at. % Sn. Sn precipitation occurred at a higher temperature than the crystallization in these specimens, and the difference between the crystallization and Sn precipitation temperatures became large with decreasing Sn concentration. Because of the existence of this temperature difference, a temperature window for suppressing Sn segregation existed. We demonstrated that large GeSn grains with high Sn concentration could be realized by annealing the specimens within the temperature window.

DOI： 10.1063/1.5086480

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Compositional effects on radiation tolerance of amorphous silicon oxycarbide 査読有り

Mizuguchi S., Inoue S., Ishimaru M., Su Q., Nastasi M.

Journal of Nuclear Materials 518 241 - 246 2019年05月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 Elsevier B.V. Relationships between amorphous structures and radiation tolerance of silicon oxycarbide (SiOC) glasses with different composition, SiO 2 :SiC = 2:1 (SiO 2 -rich), 1:1 (equiatomic), and 1:2 (SiC-rich), were examined by transmission electron microscopy and atomic pair-distribution function (PDF). These specimens were irradiated with 120 keV helium (He) ions at room temperature. The PDF results indicated that the structure of SiOC alloys are almost the same in irradiation and implantation regions. It was found that SiO 2 -rich specimens show a greater radiation resistance than SiC-rich ones: the formation of He bubbles was highly suppressed in the SiO 2 -rich and equiatomic compositions after even 90 at.% He implantation, whereas pronounced swelling occurred in the SiC-rich composition. The first sharp diffraction peak revealed that the size of network voids formed by connecting the SiO x C 4-x tetrahedra in SiO 2 -rich and equiatomic specimens is much larger than the diameter of He atom, suggesting that He atoms can easily migrate in the amorphous SiOC networks.

DOI： 10.1016/j.jnucmat.2019.03.012

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Nonlocal self-organization of long stacking faults from highly strained nanocomposite film of complex oxide 査読有り

Horide T., Ishimaru M., Sato K., Matsumoto K.

Physical Review Materials 3 ( 1 ) 2019年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 American Physical Society. Elastic strain and defects are important key words for controlling structure and properties in films. While epitaxial strain and misfit dislocations have been discussed in conventional films, the evolution of strain and defect can be significantly varied by nanocomposite strain and complicated defects in oxides. In the present study, long stacking faults with a spacing of 5-30 nm and a length of >500nm were self-organized by ex situ annealing highly strained nanocomposite films of YBa2Cu3O7-δ(YBCO)+BaMO3(M=Hf,Sn). It is surprising that the nonlocal nature of stacking faults, namely, the structural correlation over >500nm, was observed in spite of the local configuration of the nanocomposite interface. This kind of structural variation was not observed in the pure YBCO film without nanorods, even when the same annealing was performed. A strain energy analysis showed that the stacking fault formation led to the strain energy minimum by reducing the nanocomposite strain. The layered structure of YBCO stacking faults and the large nanocomposite strain realized the present nonlocal self-organization, which is not observed in the conventional systems with epitaxial strain and misfit dislocations.

DOI： 10.1103/PhysRevMaterials.3.013403

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特集にあたって査読有り

石丸学

顕微鏡 ( 公益社団法人日本顕微鏡学会 ) 54 ( 3 ) 109 - 109 2019年01月

低エネルギー電子線照射によるアモルファスGeSnの結晶化査読有り

石丸学, 仲村龍介

顕微鏡 ( 公益社団法人日本顕微鏡学会 ) 54 ( 3 ) 126 - 130 2019年01月

担当区分：筆頭著者記述言語：日本語掲載種別：記事・総説・解説・論説等（学術雑誌）

<p>材料が照射場に曝されると欠陥が導入され，欠陥蓄積に伴い構造変化が引き起こされる．照射環境下における材料の損傷過程は，「はじき出し効果」と「電子励起効果」によるものに大別される．電子線照射においては，加速電圧が高いときには前者が，低いときには後者が顕著になる．これらの効果は構造解析に対して負の影響を与えるため，電子顕微鏡観察に際しては極力避けるべきものである．一方，照射効果を利用することにより，通常の手法では実現することが難しい平衡状態から離れた材料の創製が可能である．本稿では，低エネルギー電子線照射によるアモルファスの結晶化を利用して，次世代フレキシブルディスプレイとしての応用が期待されている多結晶GeSn薄膜を，非熱的過程により作製した例を紹介する．</p>

DOI： 10.11410/kenbikyo.54.3_126

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130007783749

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