1
|
Wang Y, Ding J, Fan Z, Tian L, Li M, Lu H, Zhang Y, Ma E, Li J, Shan Z. Tension-compression asymmetry in amorphous silicon. NATURE MATERIALS 2021; 20:1371-1377. [PMID: 34059813 DOI: 10.1038/s41563-021-01017-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
Hard and brittle materials usually exhibit a much lower strength when loaded in tension than in compression. However, this common-sense behaviour may not be intrinsic to these materials, but arises from their higher flaw sensitivity to tensile loading. Here, we demonstrate a reversed and unusually pronounced tension-compression asymmetry (tensile strength exceeds compressive strength by a large margin) in submicrometre-sized samples of isotropic amorphous silicon. The abnormal asymmetry in the yield strength and anelasticity originates from the reduction in shear modulus and the densification of the shear-activated configuration under compression, altering the magnitude of the activation energy barrier for elementary shear events in amorphous Si. In situ coupled electrical tests corroborate that compressive strains indeed cause increased atomic coordination (metallization) by transforming some local structures from sp3-bonded semiconducting motifs to more metallic-like sites, lending credence to the mechanism we propose. This finding opens up an unexplored regime of intrinsic tension-compression asymmetry in materials.
Collapse
Affiliation(s)
- Yuecun Wang
- Center for Advancing Materials Performance from the Nanoscale and Hysitron Applied Research Center in China, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
| | - Jun Ding
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
| | - Zhao Fan
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Lin Tian
- Institute of Materials Physics, University of Göttingen, Niedersachsen, Germany
| | - Meng Li
- Center for Advancing Materials Performance from the Nanoscale and Hysitron Applied Research Center in China, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
| | - Huanhuan Lu
- Center for Advancing Materials Performance from the Nanoscale and Hysitron Applied Research Center in China, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
| | - Yongqiang Zhang
- Center for Advancing Materials Performance from the Nanoscale and Hysitron Applied Research Center in China, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
| | - En Ma
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China.
| | - Ju Li
- Department of Nuclear Science and Engineering, Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Zhiwei Shan
- Center for Advancing Materials Performance from the Nanoscale and Hysitron Applied Research Center in China, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China.
| |
Collapse
|
2
|
Kumar N, Kozakov AT, Nezhdanov AV, Garakhin SA, Polkovnikov VN, Chkhalo NI, Mashin AI, Nikolskii AV, Scrjabin AA. Phonon, plasmon and electronic properties of surfaces and interfaces of periodic W/Si and Si/W multilayers. Phys Chem Chem Phys 2021; 23:15076-15090. [PMID: 34231591 DOI: 10.1039/d1cp01986d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The phonon and plasmon excitations and electronic properties of interfaces of periodic W/Si and Si/W multilayer structures were investigated. The Boson band originated from quasilocal surface acoustic phonons for ultrathin Si layers, excited by Raman scattering. In confined Si layers, a small fraction of crystalline Si nanoclusters were embedded within a large volume fraction of amorphous Si (a-Si) nanoclusters. The size of the a-Si nanoclusters was smaller for the thinner Si layer in the periodic layers. The plasmon energy in the Si layer was blueshifted with a decrease in the thickness of this layer. This was explained by the size-dependent quantization of plasmon shift. The valence band spectra comprised a substantial fine structure, which is associated with the interaction of valence orbitals of the W and Si atoms at the interface boundaries. For thinner Si layers, the binding interaction of W5d and Si3p states leads to the splitting of the density of states near the Fermi level in the energy range of 1.5-5 eV. However, the energy splitting with two maxima was observed at 0.7 and 2.4 eV for thicker layers. Thus, the results of X-ray photoelectron spectroscopy have indicated that the interface of W/Si multilayers consists of metal-enriched tungsten silicide. Both the atomic structure and the elemental composition of the silicide were modified with a change in the thickness of the Si layers. This novel investigation could be essential for designing nanomirrors with higher reflectivity.
Collapse
Affiliation(s)
- Niranjan Kumar
- Institute for Physics of Microstructures RAS, Afonino, Nizhny Novgorod 603087, Russia.
| | - Alexey T Kozakov
- Research Institute of Physics, Southern Federal University, 194 Stachki Avenue, Rostov-on-Don 344090, Russia.
| | - Aleksey V Nezhdanov
- Laboratory of Functional Nanomaterials, Lobachevsky State University, Nizhny Novgorod 603950, Russia
| | - Sergey A Garakhin
- Institute for Physics of Microstructures RAS, Afonino, Nizhny Novgorod 603087, Russia.
| | | | - Nikolay I Chkhalo
- Institute for Physics of Microstructures RAS, Afonino, Nizhny Novgorod 603087, Russia.
| | - Aleksandr I Mashin
- Laboratory of Functional Nanomaterials, Lobachevsky State University, Nizhny Novgorod 603950, Russia
| | - Anatolay V Nikolskii
- Research Institute of Physics, Southern Federal University, 194 Stachki Avenue, Rostov-on-Don 344090, Russia.
| | - Anton A Scrjabin
- Research Institute of Physics, Southern Federal University, 194 Stachki Avenue, Rostov-on-Don 344090, Russia.
| |
Collapse
|
3
|
Wang Y, Liang B, Xu S, Tian L, Minor AM, Shan Z. Tunable Anelasticity in Amorphous Si Nanowires. NANO LETTERS 2020; 20:449-455. [PMID: 31804092 DOI: 10.1021/acs.nanolett.9b04164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In situ bending tests of amorphous Si nanowires (a-Si NWs) found different elastic behavior depending on whether they were straight or curved to begin with. The axially straight NWs exhibit pure elastic deformation; however, the axially curved NWs exhibit obvious anelastic behavior when they are bent in the direction of original curvature. On the basis of STEM-EELS analysis, we propose that the underlying mechanism for this anelastic behavior is a bond-switching assisted redistribution of the nonuniform density (structure) in the curved NWs under the inhomogeneous stress field. This mechanism was further supported by the fact that the originally straight a-Si NWs also display similar anelasticity with the as-grown curved NWs after focused ion beam irradiation that can cause nonuniform structure distribution. As compared to what has been reported in other 1D materials, the anelasticity of a-Si NWs can be tuned by modifying their morphology, controlling the loading direction, or irradiating them via ion beam. Our findings suggest that a-Si NWs could be a promising material in the nanoscale damping systems, especially the semiconductor nanodevices.
Collapse
Affiliation(s)
- Yuecun Wang
- Center for Advancing Materials Performance from the Nanoscale (CAMP-NANO) and Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials , Xi'an Jiaotong University , Xi'an 710049 , P. R. China
| | - Beiming Liang
- Center for Advancing Materials Performance from the Nanoscale (CAMP-NANO) and Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials , Xi'an Jiaotong University , Xi'an 710049 , P. R. China
| | - Shuigang Xu
- Department of Physics , The Hong Kong University of Science and Technology , Hong Kong , P.R. China
| | - Lin Tian
- Center for Advancing Materials Performance from the Nanoscale (CAMP-NANO) and Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials , Xi'an Jiaotong University , Xi'an 710049 , P. R. China
- Institute of Materials Physics , University of Göttingen , Göttingen 37077 , Germany
| | - Andrew M Minor
- Department of Materials Science and Engineering , University of California , Berkeley , California 94720 , United States
- National Center for Electron Microscopy, Molecular Foundry , Lawrence Berkeley National Laboratory , 1 Cyclotron Road , Berkeley , California 94720 , United States
| | - Zhiwei Shan
- Center for Advancing Materials Performance from the Nanoscale (CAMP-NANO) and Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials , Xi'an Jiaotong University , Xi'an 710049 , P. R. China
| |
Collapse
|
4
|
Gerbig Y, Michaels C. In-situ Raman spectroscopic measurements of the deformation region in indented glasses. JOURNAL OF NON-CRYSTALLINE SOLIDS 2019; 530:https://doi.org/10.1016/j.jnoncrysol.2019.119828. [PMID: 32855570 PMCID: PMC7448610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This paper describes the design and integration of a custom-built optical instrument for in-situ Raman microscopy suitable for collecting high-quality spectroscopic data during the indentation of glass materials. It will further show that the reported experimental setup enables meaningful in-situ spectroscopic observations during indentation of fused silica at forces in the millinewton range. The aim of the paper is to demonstrate the vital importance of matching the analysis volume of the Raman microscope with the indentation-induced deformation volume to capture the full extent of the related spectral alterations by minimizing spectral contributions from the unperturbed bulk material (in-situ and ex-situ) and indenter probe (in-situ only). In this context, the paper will also touch upon possible pitfalls in ex-situ and in-situ Raman measurements on indented glasses in cases where the analysis and deformation volumes are not well matched and describe the misinterpretations that may result.
Collapse
Affiliation(s)
- Y.B. Gerbig
- Material Measurement Laboratory, 100 Bureau Drive, Gaithersburg, MD 20899, United States
| | - C.A. Michaels
- Material Measurement Laboratory, 100 Bureau Drive, Gaithersburg, MD 20899, United States
| |
Collapse
|
5
|
Gerbig YB, Michaels CA, Cook RF. In situ observations of Berkovich indentation induced phase transitions in crystalline silicon films. SCRIPTA MATERIALIA 2016; 120:19-22. [PMID: 27325910 PMCID: PMC4908827 DOI: 10.1016/j.scriptamat.2016.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The pressure induced phase transitions of crystalline Si films were studied in situ under a Berkovich probe using a Raman spectroscopy-enhanced instrumented indentation technique. The observations suggested strain and time as important parameters in the nucleation and growth of high-pressure phases and, in contrast to earlier reports, indicate that pressure release is not a precondition for transformation to high pressure phases.
Collapse
Affiliation(s)
- Yvonne B Gerbig
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA; School of Engineering & Applied Science, The George Washington University, Washington, DC 20052, USA
| | - Chris A Michaels
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Robert F Cook
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| |
Collapse
|