Article
Chemistry, Multidisciplinary
Ondrej Dyck, Andrew R. Lupini, Stephen Jesse
Summary: The scanning transmission electron microscope is being developed into a platform for atomic-scale material manipulation and fabrication, offering new capabilities and applications. This approach may significantly impact research in microelectronics, quantum information science, and catalysis, by enabling precise control over atomic-scale structure and chemistry, and providing a better understanding of atomic-scale processes for larger-scale synthesis.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Ondrej Dyck, Andrew R. Lupini, Stephen Jesse
Summary: The engineering of quantum materials involves the development of tools for synthesis and characterization challenges. One key factor is atomic-scale modification for desired atomic structures. The use of scanning transmission electron microscopes (STEMs) allows for atomic-scale material manipulation but obstacles like in situ material delivery exist. This article presents progress on in situ thermal deposition platform for synthesis processes in a scanning transmission electron microscope.
Article
Chemistry, Multidisciplinary
Ondrej Dyck, Sinchul Yeom, Andrew R. Lupini, Jacob L. Swett, Dale Hensley, Mina Yoon, Stephen Jesse
Summary: Atomic-scale engineering combines bottom-up and top-down approaches to achieve atomic-scale precision patterning in twisted bilayer graphene, using an aberration-corrected scanning transmission electron microscope (STEM) and controlled ejection of carbon atoms. The application of global and local parameters allows for spontaneous arrangement of atoms and migration of adatoms on the material surface. Image-based feedback control facilitates the attachment of arbitrary patterns of atoms and atom clusters with limited human intervention. The role of substrate temperature in adatom and vacancy diffusion is studied through simulations.
ADVANCED MATERIALS
(2023)
Article
Physics, Fluids & Plasmas
R. Mark Bradley, Patrick D. Shipman
Summary: In this study, the patterns created by scanning an atomic force microscope tip over a polymer surface were investigated using a mesoscopic model. The research discovered that the steady-state solution is only stable below a critical value, beyond which periodic stick-slip motion occurs.
Article
Chemistry, Multidisciplinary
Ha Rim Lee, Da Woon Kim, Alfi Rodiansyah, Boklae Cho, Joonwon Lim, Kyu Chang Park
Summary: The structural properties of CNT cold cathodes, such as aspect ratio and tip diameter, significantly influence electron beam properties, including beam size and brightness, ultimately determining the resolution of secondary electron images obtained by SEM systems equipped with CNT cold cathode modules. Investigating these correlations is crucial for understanding the contributions of edge-emitted electrons to the total field emission current and establishing a basic model for advanced electron devices.
Article
Chemistry, Multidisciplinary
Ondrej Dyck, Andrew R. Lupini, Stephen Jesse
Summary: In this study, we demonstrate an electron beam direct-write process in an aberration-corrected scanning transmission electron microscope. This process differs from conventional electron-beam-induced deposition techniques as it uses a different mechanism and elemental tin (Sn) as a precursor to enable atom-by-atom direct writing. The atomic-sized electron beam is used to generate chemically reactive point defects in a graphene substrate, allowing the precursor atoms to migrate and bond to the defect sites for deposition.
Article
Materials Science, Multidisciplinary
Shuai Tang, Jie Tang, Eiji Okunishi, Yuki Ninota, Akira Yasuhara, Jun Uzuhashi, Tadakatsu Ohkubo, Masaki Takeguchi, Jinshi Yuan, Lu-Chang Qin
Summary: In this study, a new cold field-emission electron source utilizing a LaB6 nanoneedle has been developed, which significantly improves the resolution of transmission electron microscopes (TEM). Compared with existing electron sources, this new source exhibits a smaller energy spread and higher emission current stability. The LaB6 nanoneedle cold field-emission electron source has important implications for high-resolution imaging in TEM, as well as cryogenic electron microscopy, scanning electron microscopy, electron beam lithography, and other electron beam technologies.
Article
Materials Science, Ceramics
Ashkan Farazin, Saeid Sahmani, Maryam Soleimani, Amin Kolooshani, Saeed Saber-Samandari, Amirsalar Khandan
Summary: The study investigated the impact of TiO2 nanoparticles on the properties of PCL porous bone implants, revealing that the addition of TiO2 can alter the physical and mechanical characteristics of the scaffolds, as well as slow down the degradation rate. The fabricated bio-nanocomposite scaffolds demonstrated high total porosity and pore sizes suitable for bone cell growth, indicating potential for use as bone substitutes.
CERAMICS INTERNATIONAL
(2021)
Article
Instruments & Instrumentation
Peng Li, Yongjian Shao, Ke Xu, Xiaohui Qiu
Summary: The multi-probe atomic force microscope (MP-AFM) system developed allows for up to four probes to perform functions such as topography mapping, probing electrical properties, and local temperature measurement independently. The system uses the optical beam deflection method to measure the deflection of each cantilever and features a compact optical design and rigid actuators. High-resolution imaging in air and multi-functional characterization were demonstrated with this system.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Chemistry, Analytical
Luke Oduor Otieno, Bernard Ouma Alunda, Jaehyun Kim, Yong Joong Lee
Summary: Improving the imaging rate of a high-speed atomic force microscope requires specialized hardware and software, with ongoing efforts to enhance general applications. A compact HS-AFM scan-head design with minimal Z-scanner loading is presented in this study as an efficient solution for faster imaging.
Article
Biochemistry & Molecular Biology
Gregory Effantin, Akiko Fujiwara, Takeru Kawasaki, Takashi Yamada, Guy Schoehn
Summary: The phi RSA1 bacteriophage isolated from Ralstonia solanacearum exhibits unique structural characteristics, predominantly composed of a polymer of the gp8 protein, unlike other bacteriophages in terms of stabilization.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Materials Science, Multidisciplinary
O. Dyck, M. Ziatdinov, S. Jesse, F. Bao, A. Yousefzadi Nobakht, A. Maksov, B. G. Sumpter, R. Archibald, K. J. H. Law, S. Kalinin
Summary: The structure, bonding, and chemical dynamics of reactions at surfaces and interfaces are closely tied to the energetic landscape where each atom resides. Moving atoms under electron beam excitation can be utilized to probe energy landscapes along confined step edges, offering insights into atomic-scale potentials and the possibility for predictive atom-by-atom fabrication.
Article
Engineering, Electrical & Electronic
Shenghang Zhai, Jialin Shi, Peng Yu, Tie Yang, Yang Yang, Chanmin Su, Lianqing Liu
Summary: This study proposes a displacement sensing method with wide bandwidth and subnanometer resolution, which is not only insensitive to the material properties of the measured sample but it is also not in contact with the sample. The proposed method has a resolution of 0.21 nm, a range of 5 μm, and a bandwidth of about 515 Hz, making it suitable for micro-nano manufacturing, measurement, and motion control systems.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Biophysics
Xinfeng Shi, David Cantu-Crouch, Vinay Sharma, John Pruitt, George Yao, Kyoko Fukazawa, James Yuliang Wu, Kazuhiko Ishihara
Summary: A silicone hydrogel contact lens material with unique chemical and physical structure was enhanced through surface modification using a bioinspired MPC polymer, resulting in improved surface characteristics such as hydrophilicity and lubricity. The hydrated MPC polymer layer on the surface led to softer surface properties and reduced friction, which are expected to contribute to excellent ocular performance.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2021)
Article
Engineering, Chemical
Shizhong Cheng, Mao Sheng, Peng Xu
Summary: This study introduces an advanced technique combining SEM, EDS, and AFM to obtain the mechanical properties of organic-rich shale with high resolution. The results provide insights into the microscale mechanical properties of shale and can guide the design of hydraulic fracture optimization parameters. AFM demonstrates great potential in characterizing individual mineral components, crack topography, and mechanical properties in shale, including the layered distribution of minerals around fractures and the detection of cracks in the clay mineral layer.