Article
Materials Science, Multidisciplinary
Yi Feng, Robert Joynt
Summary: This paper discusses the problem of valley degeneracy in Si qubit devices and introduces the wiggle well architecture as a solution. The theoretical analysis and model calculations show the overall magnitude of the effect and its dependence on the wavelength of concentration oscillations. A selection rule is derived to limit the effectiveness of the wiggle well under certain circumstances.
Article
Biotechnology & Applied Microbiology
Yiding Shen, Kai Fang, Yun Xiang, Keyuan Xu, Liang Yu, Jiaquan Chen, Pingping Ma, Kaiyong Cai, Xinkun Shen, Jinsong Liu
Summary: Titanium (Ti) implants are commonly used for tooth loss treatment due to their excellent biocompatibility and mechanical properties. However, improving the biological properties of Ti implants to enhance osteointegration remains a challenge. Micro-arc oxidation (MAO) has been proposed as a surface modification technique to improve the comprehensive properties of Ti by forming a protective oxide layer.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2022)
Article
Physics, Applied
K. Nozawa, T. Ishiyama, T. Nishida, N. Saitoh, N. Yoshizawa, T. Suemasu, K. Toko
Summary: Using our solid-phase crystallization technology, we successfully synthesized n-type polycrystalline Ge thin films with the highest recorded electron mobility (450 cm(2) V-1 s(-1)) on insulating substrates. The density and barrier height of grain boundaries in the P-doped polycrystalline Ge layers were controlled by the underlayer type and a small amount of Sn addition. By growing at a low temperature (<400°C), we developed a GeSn layer on a heat-resistant polyimide film with the highest electron mobility (200 cm(2) V-1 s(-1)), directly on a flexible substrate. These achievements pave the way for high-performance polycrystalline Ge-based devices on inexpensive glass and flexible plastic substrates.
APPLIED PHYSICS LETTERS
(2023)
Article
Energy & Fuels
Leonie Jakob, Leonard Tutsch, Thibaud Hatt, Johan Westraadt, Sinoyolo Ngongo, Markus Glatthaar, Martin Bivour, Jonas Bartsch
Summary: A novel strategy is introduced to reduce the consumption of scarce materials in silicon heterojunction solar cells by replacing silver in the metallization and reducing the thickness of the indium tin oxide layer. A Ti layer serves as both the contact layer and capping layer, enabling the use of a thinner transparent conductive oxide. The nonaqueous electrolyte used prevents critical side reactions, and promising results are obtained with a short circuit current density of 35 mA cm(-)(2) and a cell efficiency close to 21%.
Article
Materials Science, Ceramics
Yusen Duan, Jingxian Zhang, Boan Zhou, Xiaoguang Li, Qun Wang, Ning Liu, Zhe Li, Lingfeng Wang
Summary: The study prepared high performance Si3N4 ceramic using TiO2, Y2O3, and MgO as pressureless sintering additives. Si3N4 ceramic with a relative density of 99.6% and flexural strength of 785 +/- 23.3 MPa was obtained with 3 mol% TiO2 sintered at 1800 degrees C for 2 h. After annealing at 1700 degrees C, the fracture toughness and flexural strength of samples with TiO2 additives increased, indicating improved mechanical properties after the annealing process.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Yang Zhou, Fang Yang, Cunguang Chen, Yanru Shao, Boxin Lu, Tianxing Lu, Yanli Sui, Zhimeng Guo
Summary: High-plasticity titanium materials with high oxygen content were prepared using powder metallurgy and hot rolling, resulting in increased strength due to the changes in lattice constant from the complete dissolution of oxygen and zirconium atoms. The addition of ZrO2 significantly increased both the UTS and EL of the titanium alloy, breaking the strength-ductility trade-off dilemma. The reinforcement effect of ZrO2 was calculated to be 146.7 MPa/wt% ZrO2.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Electrical & Electronic
E. Shafir, S. Zilberman, Y. London, M. Dadon, G. Berkovic, S. Vaintraub, A. Krakovich, K. Ben-Meir, T. Makmal
Summary: In this study, the results of an experiment conducted in a nuclear reactor core demonstrate that fluorine-doped fibers exhibit lower radiation-induced attenuation (RIA) than pure silica fibers at low dose levels for telecom wavelengths. However, at high dose levels, pure silica fibers show lower RIA than fluorine-doped fibers.
IEEE TRANSACTIONS ON NUCLEAR SCIENCE
(2022)
Article
Polymer Science
Zhigao Liu, Jinchi Xu, Si Cheng, Zhiyong Qin, Yunlin Fu
Summary: A self-cleaning wood surface was achieved by applying a Bi2O3-doped silica-titanium composite film onto the wood surface using the sol-gel method. The study investigated the effects of different Bi doping amounts on the structure and photocatalytic properties of the modified wood. Bi2O3 doping inhibited crystal growth of TiO2 and the phase transition from anatase to rutile. In addition, Bi2O3 improved the photocatalytic activity of the composite film by reducing the grain size of TiO2 and increasing its crystallinity.
Article
Engineering, Biomedical
Aya Ali, Sheetal Chowdhury, Mary A. A. Carr, Amol V. V. Janorkar, Mary Marquart, Jason A. A. Griggs, Joel D. D. Bumgardner, Michael D. D. Roach
Summary: Titanium anodization can produce crystalline oxides that exhibit photocatalytic reactions and reduce bacteria attachment. The addition of PANI to these surfaces can increase photocatalytic activity. This study aimed to determine the optimal concentration of aniline electrolyte to maximize PCA and reduce bacterial attachment.
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS
(2023)
Article
Environmental Sciences
Xiao Qu, Jianbin Lin, Wei Qiang, Chuntao Chen, Dongping Sun
Summary: Photocatalytic activity of Titanium dioxide (TiO2) can be enhanced through structural regulation by chemical reduction method. The modified TiO2 samples show strong light absorption ability and exhibit excellent degradation performance for various organic pollutants.
Article
Materials Science, Multidisciplinary
Alestair Wilson, Erwann Fourmond, Bilel Saidi, Benjamin Fornacciari, Solene Brottet, Marc Juhel, Mickael Gros-Jean
Summary: Fine-tuning the crystallinity and doping levels of hydrogenated microcrystalline silicon thin films is crucial for obtaining high-quality above-IC image sensors. This study investigates the structural and electrical properties of RF-PECVD-deposited microcrystalline silicon contact layers, focusing on the influence of phosphine concentration on dopant concentration, active dopant concentration, and crystallinity. A high doping level of 1.7 x 10(20) cm(-3) is achieved, and different incubation layers are obtained under different deposition conditions.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2022)
Article
Engineering, Electrical & Electronic
Konstantin K. Bobkov, Egor K. Mikhailov, Tatyana S. Zaushitsyna, Andrey A. Rybaltovsky, Svetlana S. Aleshkina, Mikhail A. Melkumov, Mikhail M. Bubnov, Denis S. Lipatov, Mikhail V. Yashkov, Alexey N. Abramov, Andrey A. Umnikov, Alexey N. Guryanov, Mikhail E. Likhachev
Summary: This study systematically investigates silica-based optical fibers with an ultra-high Yb concentration. The factors limiting the increase of Yb content in glasses and fibers are revealed, and it is shown for the first time that highly Yb-doped fibers can nearly completely lose their active properties due to concentration quenching of luminescence.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Ida Tyschenko, Fedor Tikhonenko, Anton Gutakovskii, Vladimir Vdovin, Konstantin Rudenko, Vladimir Popov
Summary: In this study, high-resistance silicon layers were formed by CO+ ion implantation and subsequent annealing on silicon substrates. The structural and electric properties of the ion-implanted layers were investigated. The results showed the formation of 3C-SiC and 6H-SiC nanocrystals in the ion-implanted layers and the positive charge compensation in the buried SiO2 layer of a silicon-on-insulator structure. The origin of these results was discussed.
Article
Chemistry, Physical
Jin Hyuck Heo, Fei Zhang, Jin Kyoung Park, Hyong Joon Lee, David Sunghwan Lee, Su Jeong Heo, Joseph M. Luther, Joseph J. Berry, Kai Zhu, Sang Hyuk Im
Summary: Surface engineering of the CsPbI3 layer with oxidized Ti3C2Tx MXene nanoplates via spray coatings resulted in highly efficient and stable p-i-n-structured CsPbI3 perovskite solar cells. The addition of OMXene provided a physical barrier against moisture and improved charge separation at the perovskite-electron transporting layer interface, leading to the demonstration of efficient CsPbI3/OMXene-based p-i-n devices with good stability.
Article
Nanoscience & Nanotechnology
Pei Cui, Panpan Zhang, Xueli Chen, Xiuli Chen, Tao Wan, Yu Zhou, Mingru Su, Yunjian Liu, Haolan Xu, Dewei Chu
Summary: TiNb2O7 has shown great potential as an anode material for lithium-ion batteries due to its high specific capacity and safety. However, its poor ion and electron conductivity have limited its further development. In this study, we successfully improved the ion and electron transport of TiNb2O7 by doping with chlorine and creating oxygen vacancies. These modifications regulated the energy band and crystal structure, leading to enhanced lithium-ion transport behavior and superior rate performance.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Rodrigo Blasco, Arantzazu Nunez-Cascajero, Marco Jimenez-Rodriguez, Daniel Montero, Louis Grenet, Javier Olea, Fernando B. Naranjo, Sirona Valdueza-Felip
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2019)
Article
Physics, Condensed Matter
Rodrigo Blasco, Sirona Valdueza-Felip, Daniel Montero, Michael Sun, Javier Olea, Fernando B. Naranjo
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2020)
Article
Chemistry, Physical
J. Olea, S. Algaidy, A. del Prado, E. Garcia-Hemme, R. Garcia-Hernansanz, D. Montero, D. Caudevilla, G. Gonzalez-Diaz, E. Soria, J. Gonzalo
JOURNAL OF ALLOYS AND COMPOUNDS
(2020)
Article
Chemistry, Physical
Sirona Valdueza-Felip, Rodrigo Blasco, Javier Olea, Alba Diaz-Lobo, Alejandro F. Brana, Fernando B. Naranjo
Article
Nanoscience & Nanotechnology
Hemi H. Gandhi, David Pastor, Tuan T. Tran, Stefan Kalchmair, Lachlan A. Smillie, Jonathan P. Mailoa, Ruggero Milazzo, Enrico Napolitani, Marko Loncar, James S. Williams, Michael J. Aziz, Eric Mazur
Article
Physics, Applied
Hemi H. Gandhi, David Pastor, Tuan T. Tran, S. Kalchmair, L. A. Smilie, Jonathan P. Mailoa, Ruggero Milazzo, Enrico Napolitani, Marco Loncar, James S. Williams, Michael J. Aziz, Eric Mazur
PHYSICAL REVIEW APPLIED
(2020)
Article
Nanoscience & Nanotechnology
Eric Garcia-Hemme, Daniel Caudevilla, Sari Algaidy, Francisco Perez-Zenteno, Rodrigo Garcia-Hernansanz, Javier Olea, David Pastor, Alvaro del Prado, Enrique San Andres, Ignacio Martil, German Gonzalez-Diaz
Summary: This study presents the potential of Ti hyperdoped-Si as a material for room-temperature infrared photodetection technologies. Through a combination of ion implantation and laser-based methods, thin hyperdoped single-crystal Si layers with high Ti concentrations were obtained. The research reveals that transport in the Ti hyperdoped Si/p-Si photodiode is dominated by two mechanisms at different bias levels and proposes a model to relate optoelectronic mechanisms to sub-bandgap optical transitions.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
D. Caudevilla, S. Algaidy, F. Perez-Zenteno, S. Duarte-Cano, R. Garcia-Hernansanz, J. Olea, E. San Andres, A. del Prado, R. Barrio, I Torres, E. Garcia-Hemme, D. Pastor
Summary: In this study, we have successfully hyperdoped germanium with tellurium and investigated its electrical properties and absorption characteristics. The hyperdoped layers exhibit good crystallinity and sub-bandgap absorption, making them a promising candidate for a new generation of short-wavelength-infrared photodetectors.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
R. Garcia-Hernansanz, S. Duarte-Cano, F. Perez-Zenteno, D. Caudevilla, S. Algaidy, E. Garcia-Hemme, J. Olea, D. Pastor, A. Del Prado, E. San Andres, I Martil, E. Ros, J. Puigdollers, P. Ortega, C. Voz
Summary: According to intermediate band theory, this study used a hyperdoped semiconductor approach to create a proof of concept for different silicon-based intermediate band solar cells. The results showed an increase in external quantum efficiency in the silicon sub-bandgap region, suggesting potential applications in solar cells and infrared photodetectors. To understand the transport mechanisms in hyperdoped semiconductors within a solar cell, J-V characteristics were measured at different temperatures and a new model with three elements was proposed.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
J. Olea, G. Gonzalez-Diaz, D. Pastor, E. Garcia-Hemme, D. Caudevilla, S. Algaidy, F. Perez-Zenteno, S. Duarte-Cano, R. Garcia-Hernansanz, A. del Prado, E. San Andres, I Martil
Summary: In this study, Si samples were implanted with high doses of Ti and processed using rapid thermal annealing (RTA) to recover crystal quality, with some samples processed by pulsed-laser melting for comparison. The electronic transport properties were measured at variable temperatures and analyzed. The results showed that the surface layers of RTA samples had negligible conductivity due to defects, while the implantation tail region had measurable conductivity due to high electron mobility. This region exhibited the activation of a very shallow donor and a deep donor level, with the suggestion that it originated from Ti-Si complexes. A decoupling effect between the implanted layer and the substrate was also observed, and a bilayer model was used to fit the measured properties.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
J. Olea, G. Gonzalez-Diaz, D. Pastor, E. Garcia-Hemme, D. Caudevilla, S. Algaidy, F. Perez-Zenteno, S. Duarte-Cano, R. Garcia-Hernansanz, A. del Prado, E. San Andres, I Martil, Yao-Jen Lee, Tzu-Chieh Hong, Tien-Sheng Chao
Summary: Microwave annealing (MWA) processes were used for the first time to obtain Ti supersaturated Si. High Ti doses were ion implanted on Si substrates and subsequently MWA processed to recrystallize the amorphous layer. The resulting layers were monocrystalline with a high density of defects. Ti depth profiles indicate that diffusion is avoided once recrystallization is produced. Finally, the electronic transport properties measurements point to a decoupling effect between the Si:Ti layer and the substrate. The implanted layer present also a shallow donor and very high Hall mobility.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Energy & Fuels
R. Garcia-Hernansanz, F. Perez-Zenteno, S. Duarte-Cano, D. Caudevilla, S. Algaidy, E. Garcia-Hemme, J. Olea, D. Pastor, A. del Prado, E. San Andres, I. Martil, E. Ros, J. Puigdollers, P. Ortega, C. Voz
Summary: In this article, the effect of the inversion charge (Q(inv)) in a solar cell based on the hole-selective characteristic of substoichiometric molybdenum oxide (MoOx) and vanadium oxide (VOx) deposited directly on n-type silicon is studied. The capacitance-voltage (C-V) curves of the solar cells are measured at different frequencies, and the variation of space charge and the existence of Q(inv) in the c-Si inverted region are explained. The high-frequency capacitance measurements follow the Schottky metal-semiconductor theory, indicating a low inversion charge influence. However, an increase in capacitance is observed at frequencies lower than 20 kHz, which is related to the contribution of the inversion charge. Furthermore, the built-in voltage potential is obtained and new evidence about the conduction process in this structure is shown. This article provides a better understanding of the transition metal oxide/n-type crystalline silicon heterocontact.
IEEE JOURNAL OF PHOTOVOLTAICS
(2023)
