Article
Chemistry, Physical
Sami Ullah, Gary Wan, Christos Kouzios, Cameron Woodgate, Mattia Cattelan, Neil Fox
Summary: Wideband gap diamond-based materials are being studied for energy harvesting and quantum applications, with Sn identified as a potential candidate for negative electron affinity on diamond surfaces. Experimental results show that SnO termination on diamond surfaces can lead to NEA and reduce the work function, making it a stable option for device applications. The intercalation of Li with SnO planes enhances the stability of LiO termination on diamond surfaces and reduces the work function even further, showing potential for more efficient diamond surface terminations.
APPLIED SURFACE SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Alex K. Schenk, Michael J. Sear, Nikolai Dontschuk, Anton Tadich, Alastair Stacey, Chris I. Pakes
Summary: This study investigated the fluorination of the silicon-terminated diamond surface using a molecular fluorine source. The results showed that the fluorine source reacted with the silicon termination, resulting in an inhomogeneous fluorinated surface. Even after the removal of the fluorine source, partial fluorination remained. The study demonstrated the potential of the silicon-terminated diamond surface for modifying the surface properties of diamond.
DIAMOND AND RELATED MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Patrick R. Raffaelle, George T. Wang, Alexander A. Shestopalov
Summary: The focus of this study was to demonstrate the vapor-phase halogenation of Si(100) and evaluate the inhibiting ability of the halogenated surfaces towards atomic layer deposition of aluminum oxide (Al2O3). The results showed that halogenated surfaces effectively inhibited the formation of aluminum oxide, with chlorinated surfaces exhibiting the best stability.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Chenxi Li, Eliezer F. Oliveira, Abhijit Biswas, Anand B. Puthirath, Xiang Zhang, Atin Pramanik, Elias J. Garratt, Mahesh R. Neupane, Bradford B. Pate, Anthony Glen Birdwell, Tony G. Ivanov, Tanguy Terlier, Robert Vajtai, Pulickel M. Ajayan
Summary: Diamond surface functionalization has attracted significant research interest, particularly H-termination due to its ability to enhance surface conductivity. This study focused on exploring the attachment of different functional groups, such as nitrogen and sulfur heteroatoms, on the diamond surface and their impact on electronic structure. The functionalized diamond surfaces were found to possess higher conductivity than H-terminated diamonds and showed a downshift in the conduction band minimum and valence band maximum, indicating a reduced bandgap. These findings suggest the potential of heteroatom functionalizations on diamond surfaces for various electronic applications.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Tetsuya Tatsuishi, Kyotaro Kanehisa, Taisuke Kageura, Takahiro Sonoda, Yuki Hata, Kazuto Kawakatsu, Takashi Tanii, Shinobu Onoda, Alastair Stacey, Shozo Kono, Hiroshi Kawarada
Summary: This paper presents a new methodology for fabrication of 2D aligned NV ensembles by using pure diamond growth and high nitrogen coverage on (111) surface. The resulting 2D NV ensembles have high alignment ratio and long coherence time. Introducing thermal annealing of the nitrogen termination improves alignment rate.
Article
Chemistry, Physical
Ramiz Zulkharnay, Neil L. Allan, Paul W. May
Summary: Surface modification of diamond with the addition of metals or other electropositive adsorbates can result in negative electron affinity (NEA). Scandium adsorption on diamond is energetically favorable, especially on the oxygenated surface. Most stable scandium adsorption configurations possess NEA, with the highest NEA value found on the oxygenated diamond surface.
Article
Materials Science, Multidisciplinary
Mengmeng Gong, Qiliang Wang, Nan Gao, Hongdong Li
Summary: Three types of nitrogen coverage configurations on diamond (100) surface were predicted to be dynamically and thermally stable, with positive electron affinities. The energy levels of N-termination contribute to the bandgap of bulk diamond, providing theoretical guidance for the design and fabrication of N-terminated diamond-based electronic devices.
DIAMOND AND RELATED MATERIALS
(2021)
Article
Chemistry, Physical
T. V. Pavlova, V. M. Shevlyuga, B. V. Andryushechkin, K. N. Eltsov
Summary: This study reports the removal of individual halogen atoms from Si(100)-2x1-Cl and -Br surfaces in STM. The charge states of DBs formed on the Si surface can be manipulated, allowing for tuning the reactivity of the Cl- and Br-terminated surfaces.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
B. Oslinker, D. Hoxley, A. Tadich, A. Stacey, S. Yianni, R. Griffin, E. Gill, C. I. Pakes, A. K. Schenk
Summary: High-resolution core-level photoemission and Kelvin probe were used to investigate the surface transfer doping of oxidised silicon-terminated (111) diamond with the molecular acceptor MoO3. It was found that a downward shift in the Fermi level position, indicating p-type surface doping, was only observed for MoO3 coverages in the range of 0.2-0.6 ML and above. For lower MoO3 coverages, the appearance of distinct charge states of MoO3 could be attributed to electron transfer from surface charge traps with a estimated density in the range of 1-3 x 1013 cm-2. Atomic force microscopy imaging indicated significant disorder on the (111) diamond surface compared to similarly prepared (100) diamond surfaces.
DIAMOND AND RELATED MATERIALS
(2023)
Article
Chemistry, Physical
F. N. Li, Y. Li, H. W. Bao, H. X. Wang, F. Ma
Summary: In this study, hydroxyl terminated diamond (OH-diamond) was obtained by hydroxide ion treatments in deionized water, and its surface was chemically functionalized with carboxyl groups. Silanization was achieved by condensation reaction of 3-aminopropyltriethoxysilane (APTES) with the surface C-OH groups. The stability of OH-diamond surface was investigated through simulations and calculations.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Wei Shen, Gai Wu, Lijie Li, Hui Li, Sheng Liu, Shengnan Shen, Diwei Zou
Summary: This study investigates the effects of different surface modifications on diamond (110) surface on NV centers and finds that the oxygen-terminated and nitrogen-terminated, as well as hydrogen-terminated surfaces may not be suitable for shallow NV centers, while the fluorine-terminated surface is a promising candidate.
Article
Chemistry, Physical
Yan-Feng Wang, Wei Wang, Jinjia Wei, Bo Jiao, Defei Xu, Xiaohui Chang, Haris Naeem Abbasi, Wangzhen Song, Genqiang Chen, Hong-Xing Wang
Summary: A novel method of electrochemically modifying hydrogen-terminated diamond surface with LiF dielectric in MISFETs was proposed in this communication, resulting in the formation of CeF bonds. A model was introduced to explain the electrochemistry modification on MISFETs, with the theoretical electrolysis voltage of F- calculated to be around 3.8V in line with the experimental value of -5V.
Article
Engineering, Electrical & Electronic
Yu Fu, Te Bi, Yuhao Chang, Ruimin Xu, Yuehang Xu, Hiroshi Kawarada
Summary: In this study, excellent electrical performances were achieved for diamond metal-oxide-semiconductor field-effect transistors (MOSFETs) using chemical-vapor-deposition grown SiO2 as the filling insulator. The surfaces of the SiO2 films were treated with oxygen plasma to remove the carbon-rich layer. The devices exhibited high on-off ratios and subthreshold slopes at elevated temperatures, indicating potential applications in industrial settings.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Jesus Canas, Daniel F. Reyes, Alter Zakhtser, Christian Dussarrat, Takashi Teramoto, Marina Gutierrez, Etienne Gheeraert
Summary: The synthesis development of silicon oxide atomic layer deposition has opened the possibility of using it as a dielectric material in diamond electronics. The study of the heterojunction between deposited silicon oxide and oxygen-terminated diamond has provided insights into the properties and interface of the materials.
Article
Chemistry, Physical
Pengfei Qiao, Kang Liu, Sen Zhang, Zhenhua Su, Bing Dai, Jiecai Han, Jiaqi Zhu
Summary: The energy band diagram of the Si-treated diamond surface was investigated experimentally, which showed similarities to a hydrogen-terminated surface. This may be the origin of the reported C-Si diamond two-dimensional hole gas channel.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Coatings & Films
Aaqil Rifai, Daniel Creedon, Nhiem Tran, Maryam Hejazi, David Garrett, Andrew D. Greentree, Elena Pirogova, Alastair Stacey, Kate Fox
Summary: The desire for diamond as a conformal thin-film coating for 3D devices due to its extreme hardness, durability, and biocompatibility has led to recent advancements in microwave plasma CVD techniques. By using in-cavity Faraday cages to isolate the 3D samples from the microwave cavity, more uniform growth of CVD polycrystalline diamond coatings on complex-shaped structures has been demonstrated. This technique disrupts the distribution of the microwave plasma around the 3D structure but still allows for growth of relatively uniform micro-crystalline and faceted PCD films over the entire exposed 3D sample surface.
SURFACE & COATINGS TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Nitu Syed, Alastair Stacey, Ali Zavabeti, Chung Kim Nguyen, Benedikt Haas, Christoph T. Koch, Daniel L. Creedon, Enrico Della Gaspera, Philipp Reineck, Azmira Jannat, Matthias Wurdack, Sarah E. Bamford, Paul J. Pigram, Sherif Abdulkader Tawfik, Salvy P. Russo, Billy J. Murdoch, Kourosh Kalantar-Zadeh, Chris F. McConville, Torben Daeneke
Summary: In this study, ultrathin indium nitride nanosheets were synthesized using a liquid metal-based printing method and a microwave plasma-enhanced nitridation reaction. The nanosheets exhibited high carrier mobilities and quantized states, making them promising for applications in optoelectronic devices and 2D heterostructures.
Article
Physics, Applied
Steve A. Yianni, Martin Hofmann, Alex K. Schenk, Christoph Reuter, Ivo W. Rangelow, Christopher I. Pakes
Summary: This article demonstrates a method for direct-write modification of a diamond surface at the nanometer scale. By using an atomic force microscope tip as an emission source and the surface conductivity of hydrogen-terminated diamond, nano-structuring of diamond surfaces is achieved under ambient conditions. The experimental results show that features on the micrometer scale can be controllably created on the diamond surface.
APPLIED PHYSICS LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Alex K. Schenk, Michael J. Sear, Nikolai Dontschuk, Anton Tadich, Alastair Stacey, Chris I. Pakes
Summary: This study investigated the fluorination of the silicon-terminated diamond surface using a molecular fluorine source. The results showed that the fluorine source reacted with the silicon termination, resulting in an inhomogeneous fluorinated surface. Even after the removal of the fluorine source, partial fluorination remained. The study demonstrated the potential of the silicon-terminated diamond surface for modifying the surface properties of diamond.
DIAMOND AND RELATED MATERIALS
(2022)
Article
Physics, Multidisciplinary
Marco Capelli, Lukas Lindner, Tingpeng Luo, Jan Jeske, Hiroshi Abe, Shinobu Onoda, Takeshi Ohshima, Brett Johnson, David A. Simpson, Alastair Stacey, Philipp Reineck, Brant C. Gibson, Andrew D. Greentree
Summary: The nitrogen-vacancy colour centre in diamond is an important solid-state quantum system with various applications. This study reveals that nearby nitrogen impurities can quench the emission of nitrogen-vacancy centres, resulting in a reduced fluorescence quantum yield. The researchers also measured the emission properties of these centres in synthetic diamond samples with different concentrations of nitrogen impurities. The results show that increasing nitrogen density leads to a decrease in lifetime and fluorescence quantum yield of nitrogen-vacancy centres.
NEW JOURNAL OF PHYSICS
(2022)
Article
Chemistry, Physical
Samira Falahatdoost, Andre Chambers, Alastair Stacey, Steven Prawer, Arman Ahnood
Summary: The study investigates the impact of various oxygen treatment methods on nitrogen-doped ultrananocrystalline diamond (N-UNCD) and finds that oxygen furnace annealing greatly enhances its near-infrared photoresponsivity. The improvement in photo current is mainly attributed to the changes in chemical species on the surface. This finding positions N-UNCD as a promising candidate for next-generation photoelectrodes in photobiomodulation.
SURFACES AND INTERFACES
(2022)
Article
Physics, Applied
S. C. Scholten, G. J. Abrahams, B. C. Johnson, A. J. Healey, I. O. Robertson, D. A. Simpson, A. Stacey, S. Onoda, T. Ohshima, T. C. Kho, J. Ibarra Michel, J. Bullock, L. C. L. Hollenberg, J-P Tetienne
Summary: Magnetic imaging with nitrogen-vacancy centers in diamond, known as quantum diamond microscopy, is used to map charge currents in solid-state devices. This study applies this technique to photovoltaic (PV) devices and develops a widefield nitrogen-vacancy microscope for independent stimulus and measurement. The results demonstrate the imaging of magnetic field and photocurrents in prototype PV devices, offering a versatile analysis platform for research on emerging PV technologies.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Applied
Alexander A. Wood, Alastair Stacey, Andy M. Martin
Summary: Researchers demonstrate a quantum sensing technique that surpasses the sensitivity of conventional T2*-limited dc magnetometry by more than an order of magnitude. By using rotating nitrogen-vacancy centers in a diamond, they achieve enhanced magnetic sensitivity and investigate the relationship between measurement time, rotation speed, and sensitivity. This method selectively up-converts the dc field of interest while preserving quantum coherence of the sensor.
PHYSICAL REVIEW APPLIED
(2022)
Article
Materials Science, Multidisciplinary
B. Oslinker, D. Hoxley, A. Tadich, A. Stacey, S. Yianni, R. Griffin, E. Gill, C. I. Pakes, A. K. Schenk
Summary: High-resolution core-level photoemission and Kelvin probe were used to investigate the surface transfer doping of oxidised silicon-terminated (111) diamond with the molecular acceptor MoO3. It was found that a downward shift in the Fermi level position, indicating p-type surface doping, was only observed for MoO3 coverages in the range of 0.2-0.6 ML and above. For lower MoO3 coverages, the appearance of distinct charge states of MoO3 could be attributed to electron transfer from surface charge traps with a estimated density in the range of 1-3 x 1013 cm-2. Atomic force microscopy imaging indicated significant disorder on the (111) diamond surface compared to similarly prepared (100) diamond surfaces.
DIAMOND AND RELATED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Pin Lyu, Joachim Sodequist, Xiaoyu Sheng, Zhizhan Qiu, Anton Tadich, Qile Li, Mark T. Edmonds, Meng Zhao, Jesuis Redondo, Martin Svec, Peng Song, Thomas Olsen, Jiong Lu
Summary: In this study, researchers demonstrated the experimental results of obtaining spin-correlated flat-band states and bandgap in a monolayer of magnetic chromium tribromide (CrBr3) grown on graphene by electric field modulation. Scanning tunneling spectroscopy (STS) studies showed that the interflat-band spacing and bandgap of CrBr3 can be continuously tuned by injecting carriers into the CrBr3/graphene system. This is due to the self-screening effect of CrBr3 induced by the injected carriers, which dominates over the weakened remote screening of the graphene substrate caused by the decreased carrier density. Precise tuning of spin-correlated flat-band states and bandgap in 2D magnets through electrostatic modulation of Coulomb interactions not only provides effective strategies for optimizing spin transport channels but also has the potential to influence exchange energy and spin-wave gap, thereby raising the critical temperature for magnetic order.
Article
Materials Science, Multidisciplinary
Kaijian Xing, Daniel L. Creedon, Golrokh Akhgar, Steve A. Yianni, Jeffrey C. McCallum, Lothar Ley, Dong-Chen Qi, Christopher Pakes
Summary: The observation of a strong and tunable spin-orbit interaction (SOI) in surface-conducting diamond opens up a new avenue for building diamond-based spintronics. By adopting a significantly improved theoretical magnetotransport model, the reduced magnetoconductance can be accurately explained both within and outside the quantum diffusive regime. Furthermore, local hole mobilities as high as 1000-3000 cm2/V s have been observed, indicating the possibility of diamond-based electronics with ultrahigh hole mobilities at cryogenic temperatures.
Article
Engineering, Electrical & Electronic
Kaijian Xing, Patjaree Aukarasereenont, Sergey Rubanov, Ali Zavabeti, Daniel L. Creedon, Wei Li, Brett C. Johnson, Christopher Pakes, Jeffrey C. McCallum, Torben Daeneke, Dong-Chen Qi
Summary: Graphene is a promising material with unique electrical and optical properties, but its high production cost and complex fabrication process have limited its widespread application. Therefore, developing a simple, low-cost, and efficient method for graphene production is of great significance.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
Manjith Bose, Daniel L. Creedon, Anders Barlow, Michael Stuiber, Georgina M. Klemencic, Soumen Mandal, Oliver Williams, Grant van Riessen, Christopher Pakes
Summary: Nanoscale superconducting quantum interference devices (nano-SQUIDs) with Dayem bridge junctions and a physical loop size of 50 nm have been fabricated in boron-doped nanocrystalline diamond films. The nonhysteretic operation of the unshunted device can be maintained in high magnetic fields, and it exhibits low flux noise and high spin sensitivity. At elevated magnetic fields, the nano-SQUID output voltage shows flux modulation, but with an increased period due to additional phase bias induced by vortices penetrating the nano-SQUID electrodes.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Golrokh Akhgar, Qile Li, Iolanda Di Bernardo, Chi Xuan Trang, Chang Liu, Ali Zavabeti, Julie Karel, Anton Tadich, Michael S. Fuhrer, Mark T. Edmonds
Summary: Understanding the air stability of MnBi2Te4 thin films is crucial for electronic devices. After exposure to air, a 2 nm thick oxide layer forms on the surface, protecting the underlying layers. The samples still exhibit metallic conduction and minimal doping. This research opens up new possibilities for handling and preparing MnBi2Te4 devices.
ACS APPLIED MATERIALS & INTERFACES
(2022)
