Technical roadmap of ultra-thin crystalline silicon-based bioelectronics
Mingyu Sang, Kyubeen Kim, D. Lee, Young Uk Cho, Jung Woo Lee, Ki Jun Yu
IF 21.3
International Journal of Extreme Manufacturing
Abstract Ultra-thin crystalline silicon stands as a cornerstone material in the foundation of modern micro and nano electronics. Despite the proliferation of various materials including oxide-based, polymer-based, carbon-based, and two-dimensional (2D) materials, crystal silicon continues to maintain its stronghold, owing to its superior functionality, scalability, stability, reliability, and uniformity. Nonetheless, the inherent rigidity of the bulk silicon leads to incompatibility with soft tissues, hindering the utilization amid biomedical applications. Because of such issues, decades of research have enabled successful utilization of various techniques to precisely control the thickness and morphology of silicon layers at the scale of several nanometres. This review provides a comprehensive exploration on the features of ultra-thin single crystalline silicon as a semiconducting material, and its role especially among the frontier of advanced bioelectronics. Key processes that enable the transition of rigid silicon to flexible form factors are exhibited, in accordance with their chronological sequence. The inspected stages span both prior and subsequent to transferring the silicon membrane, categorized respectively as on-wafer manufacturing and rigid-to-soft integration. Extensive guidelines to unlock the full potential of flexible electronics are provided through ordered analysis of each manufacturing procedure, the latest findings of biomedical applications, along with practical perspectives for researchers and manufacturers.
Strain Engineering in Perovskites: Mutual Insight on Oxides and Halides
Min‐Ju Choi, Jung Woo Lee, Ho Won Jang
IF 26.8
Advanced Materials
Perovskite materials have garnered significant attention over the past decades due to their applications, not only in electronic materials, such as dielectrics, piezoelectrics, ferroelectrics, and superconductors but also in optoelectronic devices like solar cells and light emitting diodes. This interest arises from their versatile combinations and physiochemical tunability. While strain engineering is a recognized powerful tool for tailoring material properties, its collaborative impact on both oxides and halides remains understudied. Herein, strain engineering in perovskites for energy conversion devices, providing mutual insight into both oxides and halides is discussed. The various experimental methods are presented for applying strain by using thermal mismatch, lattice mismatch, defects, doping, light illumination, and flexible substrates. In addition, the main factors that are influenced by strain, categorized as structure (e.g., symmetry breaking, octahedral distortion), bandgap, chemical reactivity, and defect formation energy are described. After that, recent progress in strain engineering for perovskite oxides and halides for energy conversion devices is introduced. Promising methods for enhancing the performance of energy conversion devices using perovskites through strain engineering are suggested.
Vanadium in strongly correlated electron system Ni1-xVxWO4: Paradoxically boosted deNOx reaction under SOx environment via modulating electron correlation
June Won Suh, Jihye Park, Si Hoon Jeong, Gi Hyun Park, Myung Sik Choi, Changhyun Jin, Jung Woo Lee, Kimoon Lee, Kimoon Lee, Bo Ra Jeong, Hong‐Dae Kim, Sun‐Dong Kim, Hak Joo Kim, Sung Eun Kim, Yunseong Ji, Hyesung Lee, Joonho Bang, Kyu Hyoung Lee, Kyu Hyoung Lee, Seung Yong Lee
Enhanced thermal conductivity and sinterability of magnesia via nano-powder addition: Control of pore formation and densification
Dong-Myeong Kim, Hye-Jeong Jang, Young Kook Moon, Jong‑Jin Choi, Byung‑Dong Hahn, Cheol‑Woo Ahn, Jung Woo Lee, Hyun-Ae Cha
IF 6.2
Journal of the European Ceramic Society
MgO ceramics are promising candidates for high thermal conductivity applications in next-generation electronics. However, their practical application is hindered by the extremely high sintering temperature and hygroscopic instability of MgO. In this study, dense MgO ceramics were achieved through the combined use of multi-scale micro/nano MgO powders and TiO 2 /Nb 2 O 5 additives under spark plasma sintering (SPS). Notably, 5 wt.% nano-MgO combined with additives enabled densification at 1200 °C with conductivities above 41 W/m·K, demonstrating the feasibility of low-temperature processing. Finally, SPS of the optimized composition achieved nearly full density and 60 W/m·K, underscoring the synergistic effect of multi-scale mixing, additives, and applied pressure, and advancing next‑gen MgO thermal‑management materials due to improved grain-boundary connectivity and heat transport. This work provides new insights into practical route for cost-effective fabrication of high-conductivity MgO ceramics at low temperature. • The addition of nano-sized MgO to micro-sized MgO enhanced densification and thermal conductivity. • The addition of nano-sized MgO and sintering additives led to a thermal conductivity of 41 W/m·K, even at 1200 °C. • Pressure-assisted sintering minimized residual pores, yielding nearly full density and 60 W/m·K.
High-Mobility Tellurium Thin-Film Transistor: Oxygen Scavenger Effect Induced by a Metal-Capping Layer
Seung-Min Lee, Seong Cheol Jang, Jimin Park, Jae Won Park, Nayoung Choi, Kwun‐Bum Chung, Jung Woo Lee, Hyun‐Suk Kim
IF 4.3
Nanomaterials
With the ongoing development of electronic devices, there is an increasing demand for new semiconductors beyond traditional silicon. A key element in electronic circuits, complementary metal-oxide semiconductor (CMOS), utilizes both n-type and p-type semiconductors. While the advancements in n-type semiconductors have been substantial, the development of high-mobility p-type semiconductors has lagged behind. Recently, tellurium (Te) has been recognized as a promising candidate due to its superior electrical properties and the capability for large-area deposition via vacuum processes. In this work, an innovative approach involving the addition of a metal-capping layer onto Te thin-film transistors (TFTs) is proposed, which significantly enhances their electrical characteristics. In particular, the application of an indium (In) metal-capping layer has led to a dramatic increase in the field-effect mobility of Te TFTs from 2.68 to 33.54 cm<sup>2</sup>/Vs. This improvement is primarily due to the oxygen scavenger effect, which effectively minimizes oxidation and eliminates oxygen from the Te layer, resulting in the production of high-quality Te thin films. This progress in high-mobility p-type semiconductors is promising for the advancement of high-performance electronic devices in various applications and industries.
Glass-Forming Ability and Crystallization Behavior of Mo-Added Fe82−xSi4B12Nb1MoxCu1 (x = 0–2) Nanocrystalline Alloy
Hyun Ah Im, Subong An, Ki-bong Kim, Sangsun Yang, Jung Woo Lee, Jae Won Jeong
IF 2.5
Metals
This study investigates the effects of molybdenum (Mo) additions on the crystallization behavior and soft magnetic properties and of Fe82-xSi4B12Nb1MoxCu1 (x = 0–2) nanocrystalline alloys. Molybdenum enhances glass-forming ability (GFA) and magnetic properties by increasing negative mixing enthalpy (∆Hmix), mixing entropy (∆Smix), and atomic size mismatch (δ), which stabilize the amorphous phase. X-ray diffraction (XRD) analysis shows that Mo addition improves amorphous phase stability, further enhancing GFA. The simultaneous addition of Mo and Nb increases mixing entropy, promotes nucleation rates, and creates favorable conditions for optimizing nanocrystallization. Upon annealing, this optimized microstructure demonstrated low coercivity and high permeability. Notably, the Fe80Si4B12Nb1Mo2Cu1 ribbon, annealed at 470 °C for 10 min, exhibited exceptional soft magnetic properties, with a coercivity of 4.54 A/m, a maximum relative permeability of 48,410, and a saturation magnetization of 175.24 emu/g. High-resolution transmission electron microscopy (TEM) revealed an average crystal size of 18.16 nm. These findings suggest that Fe82-xSi4B12Nb1MoxCu1 (x = 0–2) nanocrystalline alloys are suitable for advanced electromagnetic applications pursuing miniaturization and high efficiency.
Mechanoimmunological Control of Metastatic Site Selection
Yassmin A. Elbanna, María Tello‐Lafoz, Andrea Holland, Ye Zhang, J.W. Kwak, Zhenghan Wang, Anatoliy Yakimov, Myra Dada, Samuel Vayner, Sarah M. Duquette, Young Hun Kim, Tejus Bale, Benjamin Y. Winer, Kenny K H Yu, Joan Massagué, Jung Woo Lee, Ori Barzilai, Scott R. Manalis, Morgan Huse
bioRxiv (Cold Spring Harbor Laboratory)
Cancer cells alter their mechanical properties in response to the rigidity of their environment. Here, we explored the implications of this environmental mechanosensing for anti-tumor immunosurveillance using single cell biophysical profiling and metastasis models. Cancer cells stiffened in more rigid environments, a biophysical change that sensitized them to cytotoxic lymphocytes. In immunodeficient mice, this behavior manifested in the outgrowth of stiffer metastatic cells in the rigid bone than in the soft lung, while in immunocompetent hosts, it led to preferential elimination of stiffer cancer cells and suppression of bone metastasis. Environmentally-induced cell stiffening and immune sensitization both required Osteopontin, a secreted glycoprotein that is upregulated during bone colonization. Analysis of patient metastases spanning mechanically distinct tissues revealed associations between environmental rigidity, immune infiltration, and cancer cell stiffness consistent with mechanically driven immunosurveillance. These results demonstrate how environmental mechanosensing modulates anti-tumor immunity and suggest a mechanoimmunological basis for metastatic site selection.
Technical roadmap of ultra-thin crystalline silicon-based bioelectronics
Mingyu Sang, Kyubeen Kim, D. Lee, Young Uk Cho, Jung Woo Lee, Ki Jun Yu
IF 21.3
International Journal of Extreme Manufacturing
Abstract Ultra-thin crystalline silicon stands as a cornerstone material in the foundation of modern micro and nano electronics. Despite the proliferation of various materials including oxide-based, polymer-based, carbon-based, and two-dimensional (2D) materials, crystal silicon continues to maintain its stronghold, owing to its superior functionality, scalability, stability, reliability, and uniformity. Nonetheless, the inherent rigidity of the bulk silicon leads to incompatibility with soft tissues, hindering the utilization amid biomedical applications. Because of such issues, decades of research have enabled successful utilization of various techniques to precisely control the thickness and morphology of silicon layers at the scale of several nanometres. This review provides a comprehensive exploration on the features of ultra-thin single crystalline silicon as a semiconducting material, and its role especially among the frontier of advanced bioelectronics. Key processes that enable the transition of rigid silicon to flexible form factors are exhibited, in accordance with their chronological sequence. The inspected stages span both prior and subsequent to transferring the silicon membrane, categorized respectively as on-wafer manufacturing and rigid-to-soft integration. Extensive guidelines to unlock the full potential of flexible electronics are provided through ordered analysis of each manufacturing procedure, the latest findings of biomedical applications, along with practical perspectives for researchers and manufacturers.
Strain Engineering in Perovskites: Mutual Insight on Oxides and Halides
Min‐Ju Choi, Jung Woo Lee, Ho Won Jang
IF 26.8
Advanced Materials
Perovskite materials have garnered significant attention over the past decades due to their applications, not only in electronic materials, such as dielectrics, piezoelectrics, ferroelectrics, and superconductors but also in optoelectronic devices like solar cells and light emitting diodes. This interest arises from their versatile combinations and physiochemical tunability. While strain engineering is a recognized powerful tool for tailoring material properties, its collaborative impact on both oxides and halides remains understudied. Herein, strain engineering in perovskites for energy conversion devices, providing mutual insight into both oxides and halides is discussed. The various experimental methods are presented for applying strain by using thermal mismatch, lattice mismatch, defects, doping, light illumination, and flexible substrates. In addition, the main factors that are influenced by strain, categorized as structure (e.g., symmetry breaking, octahedral distortion), bandgap, chemical reactivity, and defect formation energy are described. After that, recent progress in strain engineering for perovskite oxides and halides for energy conversion devices is introduced. Promising methods for enhancing the performance of energy conversion devices using perovskites through strain engineering are suggested.
Vanadium in strongly correlated electron system Ni1-xVxWO4: Paradoxically boosted deNOx reaction under SOx environment via modulating electron correlation
June Won Suh, Jihye Park, Si Hoon Jeong, Gi Hyun Park, Myung Sik Choi, Changhyun Jin, Jung Woo Lee, Kimoon Lee, Kimoon Lee, Bo Ra Jeong, Hong‐Dae Kim, Sun‐Dong Kim, Hak Joo Kim, Sung Eun Kim, Yunseong Ji, Hyesung Lee, Joonho Bang, Kyu Hyoung Lee, Kyu Hyoung Lee, Seung Yong Lee