Ion-beam synthesis of epitaxial Au nanocrystals in MgO

2004 ◽  
Vol 19 (5) ◽  
pp. 1311-1314 ◽  
Author(s):  
S. Thevuthasan ◽  
V. Shutthanandan ◽  
C.M. Wang ◽  
W.J. Weber ◽  
W. Jiang ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Single Crystal ◽  
Ion Beam ◽  
Three Dimensional ◽  
Subsequent Annealing ◽  
Two Dimensional ◽  
Epitaxial Relationship ◽  
High Quality ◽  
Au Nanoclusters ◽  
Au Clusters

The formation of Au nanoclusters in MgO using ion implantation and subsequent annealing was investigated. Approximately 1200 and 1400 Au2+ ions/nm2 were implanted in MgO(100) substrates at 300 and 975 K, respectively. Subsequent annealing in air for 10 h at 1275 K promoted the formation of Au nanostructures in MgO. The sample implanted at 300 K showed severe radiation damage. In addition, two-dimensional plateletlike structures with possible composition of Au and MgO were formed during implantation in the sample that was implanted at 300 K. In contrast, Au implantation at 975 K promoted the nucleation of Au nanostructures during implantation. Subsequent annealing of both samples show three-dimensional clusters in MgO. However, the 975 K implanted sample shows clean, high-quality, single-crystal Au clusters that have an epitaxial relationship to MgO(100).

Investigation of Ga ion implantation-induced damage in single-crystal 6H-SiC

2018 ◽  
Vol 1 (2) ◽  
pp. 115-123 ◽  
Author(s):  
Zhongdu He ◽  
Zongwei Xu ◽  
Mathias Rommel ◽  
Boteng Yao ◽  
Tao Liu ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Single Crystal ◽  
Focused Ion Beam ◽  
Electron Backscatter Diffraction ◽  
Ion Beam ◽  
Implantation Dose ◽  
Formation Mechanisms ◽  
Schematic Model ◽  
Dose Threshold ◽  
Before And After

In order to investigate the damage in single-crystal 6H-silicon carbide (SiC) in dependence on ion implantation dose, ion implantation experiments were performed using the focused ion beam technique. Raman spectroscopy and electron backscatter diffraction were used to characterize the 6H-SiC sample before and after ion implantation. Monte Carlo simulations were applied to verify the characterization results. Surface morphology of the implantation area was characterized by the scanning electron microscope (SEM) and atomic force microscope (AFM). The ‘swelling effect’ induced by the low-dose ion implantation of 1014−1015 ions cm−2 was investigated by AFM. The typical Raman bands of single-crystal 6H-SiC were analysed before and after implantation. The study revealed that the thickness of the amorphous damage layer was increased and then became saturated with increasing ion implantation dose. The critical dose threshold (2.81 × 1014−3.26 × 1014 ions cm−2) and saturated dose threshold (˜5.31 × 1016 ions cm−2) for amorphization were determined. Damage formation mechanisms were discussed, and a schematic model was proposed to explain the damage formation.

Preparation of single-crystal metal substrates for the growth of high-quality two-dimensional materials

2021 ◽  
Vol 8 (1) ◽  
pp. 182-200
Author(s):  
Yanglizhi Li ◽  
Luzhao Sun ◽  
Haiyang Liu ◽  
Yuechen Wang ◽  
Zhongfan Liu
Keyword(s):  
Single Crystal ◽  
2D Materials ◽  
Controlled Growth ◽  
Two Dimensional ◽  
High Quality ◽  
Metal Substrates ◽  
Recent Advances ◽  
Two Dimensional Materials

Recent advances on preparing single-crystal metals and their crucial roles in controlled growth of high-quality 2D materials are reviewed.

Structure Refinement of CePtSi and Hydrogenation Behavior of CePdGe, CePtSi and CePtGe

2007 ◽  
Vol 62 (4) ◽  
pp. 613-616 ◽  
Author(s):  
Wilfried Hermes ◽  
Ute Ch. Rodewald ◽  
Bernard Chevalier ◽  
Rainer Pötgena
Keyword(s):  
Single Crystal ◽  
Diffraction Data ◽  
Structure Refinement ◽  
Three Dimensional ◽  
Subsequent Annealing ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydride Formation ◽  
Arc Melting ◽  
Cerium Compounds

The intermetallic cerium compounds CePdGe, CePtSi, and CePtGe were synthesized from the elements by arc-melting and subsequent annealing. The structure of CePtSi was refined from single crystal X-ray diffraction data: LaPtSi-type (ordered α-ThSi2 version), 141md, a = 419.6(1) and c = 1450.0(5) pm, wR2 = 0.0490, 362 F2 values and 16 variables. The Pt-Si distances within the three-dimensional [PtSi] network are 242 pm, indicating strong Pt-Si interactions. Hydrogenation of the three compounds at 623 K and 4 MPa H2 gave no indication for hydride formation.

Two-dimensional (PEA)2PbBr4 perovskite single crystals for a high performance UV-detector

2019 ◽  
Vol 7 (6) ◽  
pp. 1584-1591 ◽  
Author(s):  
Yunxia Zhang ◽  
Yucheng Liu ◽  
Zhuo Xu ◽  
Haochen Ye ◽  
Qingxian Li ◽  
...  
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
High Performance ◽  
Two Dimensional ◽  
Uv Detector ◽  
High Quality ◽  
Photo Response ◽  
Response Performance

A centimeter-sized high-quality two-dimensional (PEA)2PbBr4 single crystal was prepared, which exhibited superior UV photo-response performance.

scholarly journals On the correctness of mathematical models of time-of-flight cathodoluminescence of direct-gap semiconductors

2019 ◽  
Vol 30 ◽  
pp. 07014
Author(s):  
Mikhail A. Stepovich ◽  
Dmitry V. Turtin ◽  
Elena V. Seregina ◽  
Veronika V. Kalmanovich
Keyword(s):  
Electron Beam ◽  
Gallium Nitride ◽  
Initial Data ◽  
Mathematical Models ◽  
Single Crystal ◽  
Three Dimensional ◽  
Time Of Flight ◽  
Semiconductor Material ◽  
Two Dimensional ◽  
Cathodoluminescence Intensity

Two-dimensional and three-dimensional mathematical models of diffusion and cathodoluminescence of excitons in single-crystal gallium nitride excited by a pulsating sharply focused electron beam in a homogeneous semiconductor material are compared. The correctness of these models has been carried out, estimates have been obtained to evaluate the effect of errors in the initial data on the distribution of the diffusing excitons and the cathodoluminescence intensity.

Microstructure of precipitated Au Nanoclusters in Single Crystal MgO

2002 ◽  
Vol 738 ◽  
Author(s):  
C. M. Wang ◽  
S. Thevuthasan ◽  
V. Shutthanandan ◽  
A. Cavanagh ◽  
J. Walton ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Single Crystal ◽  
Critical Size ◽  
Gold Nanoclusters ◽  
Interface Structure ◽  
Feature Size ◽  
Au Nanoclusters ◽  
Au Clusters ◽  
Transmission Electron ◽  
Relationship Of

ABSTRACTGold nanoclusters dispersed in single crystal MgO were prepared by ion implantation and subsequent annealing at 1000 °C. The morphological feature, size, crystallographic orientation of the Au nanoclusters with respect to the MgO matrix, and the interface structure between the Au nanoclusters and MgO were investigated using transmission electron microscopy. During annealing, the Au clusters nucleate coherently in the MgO lattice, leading to an epitaxial orientation relationship of [010] MgO// [010]Au and (200)MgO//(200)Au that is maintained for all the Au clusters. A critical size for the coherent-semicoherent interface transition is observed to be in the range from ∼5 to 8 nm for Au clusters in MgO. Au clusters larger than this critical size exhibit faceting on the {001} planes. The precipitated Au also exhibits internal dislocations.

Structuring of Conducting Polymers by Ion Implantation

1995 ◽  
Vol 396 ◽  
Author(s):  
Klaus Edinger ◽  
Stefanie Schiestel ◽  
Gerhard K. Wolf
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ion Implantation ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Electrochemical Behaviour ◽  
Three Dimensional ◽  
Electrochemical Treatment ◽  
Lateral Structures ◽  
Scanning Electron

AbstractConducting polypyrrole polymer films have been modified by ion implantation. The resulting cross linking leads to changes in resistivity and electrochemical behaviour. By ion implantation through masks or with a focused ion beam lateral structures can be produced which can be imaged by scanning electron microscopy and optical absorption. The implanted polypyrrole layers can be removed by electrochemical treatment while not implanted regions can be electroplated. Therefore in combination with electrochemical treatment three dimensional structures have been generated and were investigated by atomic force microscopy. In order to study structures in the submicrometer range implantation experiments with a focused ion beam were performed and the minimal line widths were investigated by scanning electron microscopy.

Single Crystal Silicon Membranes

1987 ◽  
Vol 115 ◽  
Author(s):  
Andres Fernandez ◽  
P. Hren ◽  
K. C. Lee ◽  
J. Silcox
Keyword(s):  
Ion Implantation ◽  
Single Crystal ◽  
Single Crystal Silicon ◽  
Silicon Wafers ◽  
Subsequent Annealing ◽  
Crystal Silicon ◽  
Anodic Etching ◽  
Silicon Membranes

ABSTRACTSelf-supporting, thin single crystal membranes can be fabricated from silicon wafers using ion implantation, anodic etching and subsequent annealing. Typically, membranes approximately 1200Å thick and about 250μm in diameter are formed in wafers 4 mil thick. Discs surrounding the membranes can be cut out to provide suitable TEM samples. In this paper, the steps for preparing such samples are presented with as much attention paid to experimental details as possible.

scholarly journals Direct Growth of Antimonene on C-Plane Sapphire by Molecular Beam Epitaxy

2020 ◽  
Vol 10 (2) ◽  
pp. 639
Author(s):  
Minghui Gu ◽  
Chen Li ◽  
Yuanfeng Ding ◽  
Kedong Zhang ◽  
Shunji Xia ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Molecular Beam Epitaxy ◽  
Sapphire Substrate ◽  
Molecular Beam ◽  
Three Dimensional ◽  
High Mobility ◽  
Two Dimensional ◽  
Large Area ◽  
High Quality ◽  
Direct Growth

Monolayer antimony (antimonene) has been reported for its excellent properties, such as tuneable band gap, stability in the air, and high mobility. However, growing high quality, especially large-area antimonene, remains challenging. In this study, we report the direct growth of antimonene on c-plane sapphire substrate while using molecular beam epitaxy (MBE). We explore the effect of growth temperature on antimonene formation and present a growth phase diagram of antimony. The effect of antimony sources (Sb2 or Sb4) and a competing mechanism between the two-dimensional (2D) and three-dimensional (3D) growth processes and the effects of adsorption and cracking of the source molecules are also discussed. This work offers a new method for growing antimonene and it provides ideas for promoting van der Waals epitaxy.

scholarly journals Using a Three-Dimensional Reduction Method in the High-Efficiency Grain Selector and Corresponding Grain Selection Mechanism

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1781
Author(s):  
Xintao Zhu ◽  
Fu Wang ◽  
Shuaipeng Zhang ◽  
Tobias Wittenzellner ◽  
Jessica Frieß ◽  
...  
Keyword(s):  
Single Crystal ◽  
High Efficiency ◽  
Turbine Blades ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Two Dimensional ◽  
Selection Mechanism ◽  
Dimensional Reduction Method ◽  
Optimization Parameters ◽  
Dimensional Coupling

In the development of a high-efficiency grain selector, the spiral selectors are widely used in Ni-based single crystal (SX) superalloys casting to produce single crystal turbine blades. For the complex three-dimensional structure of the spiral, a 2D grain selector was designed to investigate in this paper. As a result, the parameters of two-dimensional grain selection bond and the corresponding grain selection mechanism were established, and the three-dimensional grain selection bond was designed again by means of two-dimensional coupling optimization parameters.

Sign in / Sign up

Export Citation Format

Share Document