Article
Thermodynamics
P. G. Siddappa, Andallib Tariq
Summary: Accurately estimating thermal contact conductance (TCC) is crucial for the optimal design of cryogen-free conduction-based cooling systems. This study addresses the lack of databases and reliable correlation for TCC between bare copper contacts by performing experimental studies. The results show a non-linear variation of TCC with temperature and propose an empirical correlation for TCC estimation at cryogenic temperatures.
APPLIED THERMAL ENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Cameron Foss, Zlatan Aksamija
Summary: This study investigates the temperature-dependent thermal boundary conductance (TBC) of various beyond-graphene 2D materials on different substrates, showing the effect of temperature and encapsulation on TBC. The results reveal that some 2D materials can achieve or exceed the thermal conductivity of graphene, with the potential to tune the properties through encapsulation. Additionally, promising III-V materials are identified as potential 2D materials for thermal isolation and energy scavenging applications.
Article
Chemistry, Multidisciplinary
Luis M. Mateo, Qiang Sun, Kristjan Eimre, Carlo A. Pignedoli, Tomas Torres, Roman Fasel, Giovanni Bottari
Summary: On-surface synthesis is a powerful tool for constructing large, planar, pi-conjugated structures that are inaccessible through standard solution chemistry, with graphene nanoribbons (GNRs) holding a prime position in nanoelectronics due to their outstanding properties. Using appropriately designed molecular precursors allows the synthesis of functionalized GNRs, leading to nanostructured hybrids with superior physicochemical properties. Porphyrins (Pors) stand out among potential partners for GNRs due to their rich chemistry, robustness, and electronic richness, but constructing GNR hybrids with such pi-conjugated macrocycles is challenging and examples are scarce.
Article
Biochemistry & Molecular Biology
Bingxian Ou, Junxia Yan, Qinsheng Wang, Lixin Lu
Summary: In titanium-based metal-matrix composites (MMCs), the addition of graphene as a filler can enhance thermal conductivity. Through classical molecular dynamics simulations, we explored the thermal conductance at the titanium-graphene interface and found that the thermal boundary conductance decreases with an increasing layer number, decreases under tensile strain, and increases with compressive strain.
Review
Chemistry, Physical
K. -W. A. Chee, B. K. Ghosh, I. Saad, Y. Hong, Q. H. Xia, P. Gao, J. Ye, Z. J. Ding
Summary: Carrier-selective crystalline silicon heterojunction solar cells have achieved high lab-scale efficiencies. Apart from wafer thickness design, selecting appropriate passivation schemes and materials is crucial for industrial adoption. Reducing process complexity and recombination losses are essential for maximizing performance.
Article
Materials Science, Multidisciplinary
Ning Wei, Chujia Zhou, Zhihui Li, Bingxian Ou, Kai Zhao, Peishi Yu, Shanchen Li, Junhua Zhao
Summary: The thermal properties of aluminum/graphene composites are studied, with a focus on the thermal boundary conductance of the interface and the thermal conductivity of the composites. It is found that the thermal boundary conductance decreases with increasing layer number, and the thermal conductivity increases with graphene volume content.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Fei Cao, Yang-xi Xu, Jin-chi Sui, Xing-ji Li, Jian-qun Yang, Ying Wang
Summary: This paper investigates the electrical and structural properties of Cu/Ti/Al ohmic contacts to p-type 4H-SiC with different annealing temperatures and Cu layer thicknesses. The results show that the Cu/Ti/Al contact forms ohmic contact with a contact resistivity of 1.0×10-4 Ω·cm2 after annealing at 800 degrees C. The surface roughness and number of pits on the sample surface increase with the increase of annealing temperature.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
K. M. Yang, Q. Li, Q. Zhang, G. S. Liu, J. J. Wang, Y. F. Yang, C. X. Guo, J. M. Ni, J. Song, J. Zhang, Y. Liu, T. X. Fan
Summary: Graphene/Copper composites hold great potential in thermal-management and information-transport applications. This study investigates the intrinsic relationship between microstructural characteristics and interface stability of different Gr/Cu interfaces. The results show that Gr/{10 0} Cu interfaces have higher defect sink capability, while Gr/{111}/{100} Cu interfaces possess both high defect sink capability and good interface stability.
Article
Mechanics
I Sevostianov, M. Kachanov
Summary: This study examines the incremental normal compliance of an irregular contact between two elastic half spaces, modeling the contact as an external crack. By utilizing an approximate expression for stress intensity factor and Rice's theorem, the crack compliance is evaluated. The results are applicable to a wide range of contact shapes and include the formulation of bounds similar to Hill's comparison theorem. Additionally, the study explores the relationship between elasticity and conductivity in contact conductance.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2021)
Article
Engineering, Electrical & Electronic
Tao Lin, Jianan Xie, Shaohuan Ning, Zekun Ma, Yan Mu, WanJun Sun, Sha Yang
Summary: Ni/Ge/Ni/Au multi-layer metal electrodes were prepared on N-GaAs substrate by electron-beam evaporation to investigate the effect of annealing process parameters on N-GaAs ohmic contacts. It was found that the metal-semiconductor contact changed from Schottky contact to ohmic contact as the annealing temperature increased. The specific contact resistivity of n-GaAs samples reached a minimum value at an annealing temperature of 420°C.
MICROELECTRONIC ENGINEERING
(2022)
Article
Energy & Fuels
Leo Basset, Wilfried Favre, Olivier Bonino, Julien Sudre, Gilles Menard, Jean-Pierre Vilcot
Summary: The influence of light on the contact resistivity of the electron and hole contacts of a silicon heterojunction cell was studied using the transfer length method. Results showed that measurements are more accurate in darkness and at high injection levels. Careful attention to passivation properties is needed when fabricating TLM samples.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Chemistry, Physical
Jiarui Zhu, Shuhui Huang, Zhongnan Xie, Hong Guo, Hui Yang
Summary: The study investigated the interfacial thermal conductivity of copper-graphene composites and its influencing factors. Results showed that an increase in graphene layers leads to a decrease in thermal boundary conductance, which stabilizes when the number of layers exceeds five. The atomic structure of the copper matrix, matrix length, and graphene vacancy rate also affect thermal boundary conductance.
Article
Chemistry, Physical
Zilei Wang, Jian He, Wenjie Wang, Hao Lin, Zhiyuan Xu, Qiming Liu, Shanglong Peng, Juan Hou, Deyan He, Pingqi Gao
Summary: This study investigates solution-processed alkali metal acetates as effective electron-selective contacts in c-Si solar cells, demonstrating a significant reduction in contact resistivity and high-quality surface passivation. The development of such electron-selective contacts shows enormous potential for low-cost and high-efficiency c-Si solar cells.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Chemistry, Physical
Gen Li, Bing-Zhong Hu, Wen-Hao Mao, Nuo Yang, Jing-Tao Lu
Summary: This study investigates nonequilibrium heat transport in current-carrying single-molecular junctions using machine-learning potential and molecular dynamics. The results show that single-molecular junctions with graphene electrodes generate significantly less heating than those with gold electrodes, which is attributed to the better phonon spectral overlap of graphene with molecular vibrations.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Shuhui Tao, Qian Zhang, Andrea Vezzoli, Cezhou Zhao, Chun Zhao, Simon J. Higgins, Alexander Smogunov, Yannick J. Dappe, Richard J. Nichols, Li Yang
Summary: In this study, the single-molecular conductance of a redox active viologen molecular bridge between Au|graphene electrodes was investigated in an electrochemical gating configuration. The results showed a clear off-on-off conductance switching behavior through gating of the redox state. The study also revealed that substituting one gold contact for a graphene one had a significant impact on the junction conductance values. The experimental data was compared against two theoretical models, providing insights into the charge state evolution of the molecule with electrode potential and the sequential charge transport through the redox center in the adiabatic limit. This work opens perspectives for graphene-based molecular transistors with more effective gating and a better understanding of electrochemical electron transfer at the single molecular level.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Multidisciplinary Sciences
Jeremy T. Robinson, James Culbertson, Morgann Berg, Taisuke Ohta
SCIENTIFIC REPORTS
(2018)
Article
Physics, Applied
S. G. Walton, B. M. Foley, J. Tomko, D. R. Boris, E. D. Gillman, S. C. Hernandez, A. Giri, Tz B. Petrova, R. E. Hopkins
JOURNAL OF APPLIED PHYSICS
(2018)
Article
Nanoscience & Nanotechnology
Zachariah Hennighausen, Christopher Lane, Abdelkrim Benabbas, Kevin Mendez, Monika Eggenberger, Paul M. Champion, Jeremy T. Robinson, Arun Bansib, Swastik Kar
ACS APPLIED MATERIALS & INTERFACES
(2019)
Article
Nanoscience & Nanotechnology
David A. Kidwell, Woo-Kyung Lee, Keith Perkins, Kathleen M. Gilpin, Thomas J. O'Shaughnessy, Jeremy T. Robinson, Paul E. Sheehan, Shawn P. Mulvaney
ACS APPLIED MATERIALS & INTERFACES
(2019)
Article
Multidisciplinary Sciences
Jose J. Fonseca, Andrew L. Yeats, Brandon Blue, Maxim K. Zalalutdinov, Todd Brintlinger, Blake S. Simpkins, Daniel C. Ratchford, James C. Culbertson, Joel Q. Grim, Samuel G. Carter, Masa Ishigami, Rhonda M. Stroud, Cory D. Cress, Jeremy T. Robinson
NATURE COMMUNICATIONS
(2020)
Article
Materials Science, Multidisciplinary
Brandon T. Blue, Glenn G. Jernigan, Duy Le, Jose J. Fonseca, Stephanie D. Lough, Jesse E. Thompson, Darian D. Smalley, Talat S. Rahman, Jeremy T. Robinson, Masahiro Ishigami
Article
Multidisciplinary Sciences
Soren Ulstrup, Roland J. Koch, Simranjeet Singh, Kathleen M. Mccreary, Berend T. Jonker, Jeremy T. Robinson, Chris Jozwiak, Eli Rotenberg, Aaron Bostwick, Jyoti Katoch, Jill A. Miwa
Article
Chemistry, Multidisciplinary
Gregory M. Stephen, Aubrey T. Hanbicki, Timo Schumann, Jeremy T. Robinson, Manik Goyal, Susanne Stemmer, Adam L. Friedman
Summary: The research demonstrates robust spin transport in Cd3As2 films with long spin-coherence lengths and high spin diffusion lengths, which are essential steps towards realizing spintronic devices.
Article
Multidisciplinary Sciences
Maxim K. Zalalutdinov, Jeremy T. Robinson, Jose J. Fonseca, Samuel W. LaGasse, Tribhuwan Pandey, Lucas R. Lindsay, Thomas L. Reinecke, Douglas M. Photiadis, James C. Culbertson, Cory D. Cress, Brian H. Houston
Summary: The authors present high frequency 2D acoustic cavities operating in the 50-600GHz range, showing quality factors approaching the limit set by lattice anharmonicity. Functionality expanded by heterogeneities (steps and interfaces) is demonstrated through coupled cavities and frequency comb generation.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Cherrelle J. Thomas, Jose J. Fonseca, Catalin D. Spataru, Jeremy T. Robinson, Taisuke Ohta
Summary: Efforts are being made to control the nature of interactions between ultrathin semiconductors and metals, with a focus on the impact on electronic properties. Photoelectron spectroscopy study on WS2 films supported by gold shows variations in occupied electronic states at the G point with WS2 thickness and alignment with crystalline grains of underlying Au. Interactions with interfacing materials alter the electronic properties of 2D layered materials beyond electron screening and defects.
Article
Chemistry, Multidisciplinary
Gregory M. Stephen, Ivan Naumov, Nicholas A. Blumenschein, Y. -J. Leo Sun, Jennifer E. DeMell, Sharmila N. Shirodkar, Pratibha Dev, Patrick J. Taylor, Jeremy T. Robinson, Paul M. Campbell, Aubrey T. Hanbicki, Adam L. Friedman
Summary: Heterostructures are important tools for studying new physics and device functionalities, and now there are more available materials for it. This study combines graphene and PST to create a hybrid system with enhanced properties. Experimental measurements show higher carrier mobility and magnetoresistance compared to the individual materials. The results suggest the presence of proximity-induced interface states with hybrid properties in these materials.
Article
Chemistry, Multidisciplinary
Alex Boehm, Jose J. Fonseca, Konrad Thurner, Joshua D. Sugar, Catalin D. Spataru, Jeremy T. Robinson, Taisuke Ohta
Summary: Engineering the transition metal dichalcogenide (TMD)-metal interface is critical for the development of twodimensional semiconductor devices. By studying the electronic structures of WS2-Au and WSe2-Au interfaces, we reveal nanoscale heterogeneities that affect the local Schottky barrier height. The variations in TMD work function and binding energies are attributed to different crystallite orientations in the Au contact. Leveraging this understanding, we develop Au processing techniques to reduce heterogeneity and improve TMD-Au interfaces.
Article
Chemistry, Physical
Glenn G. Jernigan, Jose J. Fonseca, Cory D. Cress, Mikhail Chubarov, Tanushree H. Choudhury, Jeremy T. Robinson
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Article
Nanoscience & Nanotechnology
Todd H. Brintlinger, Susan Buckhout-White, Nabil D. Bassim, Divita Mathur, Anirban Samanta, Jeremy T. Robinson, Juan-Carlos Idrobo, Rhonda M. Stroud, Ellen R. Goldman, Mario G. Ancona
ACS APPLIED NANO MATERIALS
(2020)
Article
Materials Science, Multidisciplinary
Woo-Kyung Lee, Jeremy J. Pietron, David A. Kidwell, Jeremy T. Robinson, Christopher L. McGann, Paul E. Sheehan, Shawn P. Mulvaney
JOURNAL OF MATERIALS CHEMISTRY C
(2019)