- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Reactive ion etching of single crystal diamond by inductively coupled plasma: State of the art and catalog of recipes
摘要： Significant technology advances in the growth of single crystal diamond (SCD) have over the past decade led to commercial offerings of high quality SCD substrates, typically available in the form of well specified plates of several square millimeters in size [1]. At the same time, the cost of such plates has considerably decreased [2], which has triggered important research and development efforts aiming to exploit the exceptional optical [3], thermal [4] and mechanical properties [5] of SCD for a variety of applications in electronics [6], photonics [7–10], optics and opto-mechanics [11] and quantum technologies [12].
关键词： Single Crystal Diamond,State of the Art,Reactive Ion Etching,Catalog of Recipes,Inductively Coupled Plasma
更新于2025-09-23 15:21:01
-
Role of microstructure and structural disorder on tribological properties of polycrystalline diamond films
摘要： Polycrystalline diamond films with systematic change in microstructure that varies from microcrystalline to nanocrystalline structure are synthesized on Si by hot filament chemical vapor deposition. The morphology and structural properties of the grown diamond films are analyzed using field emission scanning electron microscope (FESEM), atomic force microscope (AFM), X-ray diffraction and Raman spectroscopy. The average roughness and grain size of the diamond films decrease with increase in CH4 to H2 ratio from 0.5 to 3%. Also, structural disorder in these diamond films increases with decrease in grain size as evidenced from Raman spectroscopy. The coefficient of friction (CoF) is found to be very low for all the films. However, the average CoF is found to increase from 0.011 ± 0.005 to 0.03 ± 0.015 as the grain size decrease from ～1 μm down to ～20 nm. Post analysis of wear track by FESEM, AFM based nanoscale friction and Raman spectroscopy reveal that microcrystalline diamond undergoes shear induced amorphization with negligible wear rate while nanocrystalline diamond films undergo shear induced plastic deformation without amorphization. A comprehensive mechanism for the observed CoF is discussed in the framework of microstructure, structural disorder and shear induced tribo-chemical reactions at the sliding interface.
关键词： Raman spectroscopy,Tribology,Diamond,Scanning electron microscopy,Hot filament CVD,Atomic force microscopy
更新于2025-09-23 15:21:01
-
A study of deformation behavior and phase transformation in 4H-SiC during nanoindentation process via molecular dynamics simulation
摘要： The deformation behavior and phase transformation of 4H silicon carbide (4H-SiC) during nanoindentation process is investigated with a cube corner diamond indenter through molecular dynamics simulation. It is found through the research that the basal dislocations are most likely to be generated in (0001) face and the indentation process contributes to the distortion of 4H-SiC lattice. In addition, phase transformation from 4H-SiC to 3C-SiC is firstly observed via MD simulations during indentation process. Cross-sectional observation in (12 10) plain shows that 3C-SiC layers appear firstly during nanoindentation process, and the layers are observed at small indentation depth. 3C-SiC grain is generated based on 3C-SiC layers, and the transformation is more likely to appear at larger indentation depth. The phase transformation from 4H-SiC to 3C-SiC results from the shear stress induced by indenter during loading process. 3C-SiC grain and layers are both generated from the slip of 3C seeds under the influence of shear stress, and the condition of 3C-SiC grain formation is stricter. Moreover, the P-h curve is studied and the vertical deformation mode during indentation process on 4H-SiC can be reflected on P-h curve as small pop-in events. The findings are meaningful for the study of deformation mechanism of SiC and the application of SiC in precision machining.
关键词： molecular dynamics simulation,cube corner diamond indenter,3C-SiC grain,4H-SiC,phase transformation,3C-SiC layer
更新于2025-09-23 15:21:01
-
Kinetics of graphitization of thin diamond-like carbon (DLC) films catalyzed by transition metal
摘要： In this paper, we have studied the kinetics of graphitization at 773K of thin diamond-like carbon (DLC) films coated with minute amount of Ni metallic particles. DLC films are deposited at room temperature by pulsed laser deposition (PLD) on a transparent quartz substrate, and Ni is deposited on the surface of DLC using molecular beam epitaxy technique at room temperature. The ultra-high vacuum thermal (range 573-873K with 60 min annealing treatments) and kinetic (range 30-3760 min at 773K) behaviors of the deposited films are investigated. Surface and interface characterizations indicate that the growth of graphitic sp2 clusters starts at temperatures lower than 573K. The kinetics of graphitization is recorded at 773K. Thus, the continuous growth of graphitic clusters leads to a long-range kinetics. These clusters are responsible for the increase in the electrical conductivity and carrier mobility, reaching values of 6.103 Siemens/cm and 20 V/cm2?s, respectively. This continuous change is not only explained by the nucleation and growth of graphitic clusters, but also by some reorientation of them alongside both the surface and the quartz substrate. The obtained results demonstrate that thermally post-treated catalytic metal/DLC films are promising materials for conductive electrodes and sensing applications.
关键词： Raman spectroscopy,thermal treatment,electric transport measurements,optical transmission and absorption,diamond-like carbon,thin graphite films,pulsed laser deposition,metal catalyst
更新于2025-09-23 15:21:01
-
Influence of pore size of Ti substrate on structural and capacitive properties of Ti/boron doped diamond electrode
摘要： This work is aimed at understanding the influence of pore size of titanium (Ti) substrate on the capacitive properties of boron doped diamond (BDD) electrode. BDD films were deposited on Ti substrates with five different pore sizes - 2.5, 5.0, 20.0, 30.0, 50.0 mm - using hot filament chemical vapor deposition (HFCVD). The pore size of substrate was found to cause significant variations in surface structure and capacitive properties of the Ti/BDD electrodes. The optimum pore size that resulted in best surface structure and capacitive properties was found to be 30.0 mm. The Ti30.0/BDD electrode was found to possess higher sp2-C bonds content, sp3-C bond with doped boron atom, more closely interlaced grains and bigger specific surface area than other electrodes. The maximum capacitance obtained for Ti30.0/BDD electrode was 53.3 mF cm-2, with minimum impedance value Rct of 4.8 U. The minimum capacitance of 1.07 mF cm-2 was obtained for the Ti50/BDD electrode, and the maximum impedance value Rct of 290 U was obtained by the Ti20.0/BDD electrode. Furthermore, the Ti30/BDD electrode possessed a favorable electrochemical stability of capacitance retention of 89.3% after 2070 cycles. A mechanism by which pore size affects the capacitance properties of the Ti/BDD electrode is proposed and discussed in this paper.
关键词： Capacitive property,Porous titanium substrate,Boron doped diamond,Surface structure
更新于2025-09-23 15:21:01
-
Creating a switchable optical cavity with controllable quantum-state mapping between two modes
摘要： We describe how an ensemble of four-level atoms in the diamond-type configuration can be applied to create a fully controllable effective coupling between two cavity modes. The diamond-type configuration allows one to use a bimodal cavity that supports modes of different frequencies or different circular polarisations, because each mode is coupled only to its own transition. This system can be used for mapping a quantum state of one cavity mode onto the other mode on demand. Additionally, it can serve as a fast opening high-Q cavity system that can be easily and coherently controlled with laser fields.
关键词： cavity modes,diamond-type configuration,high-Q cavity,laser fields,quantum state mapping
更新于2025-09-23 15:21:01
-
Simultaneous Nano-Texturing onto a CVD-Diamond Coated Piercing Punch with Femtosecond Laser Trimming
摘要： In this study, a CVD (Chemical Vapor Deposition)-diamond coated tungsten carbide cobalt (WC (Co)) punch was trimmed to adjust its surface roughness and to significantly reduce its edge curvature for fine piercing by femtosecond laser processing. Through this laser trimming, the surface quality of the diamond coating and the punch edge profile were improved to less than 0.5 μm at the maximum roughness and 2 μm in the edge width, respectively. In parallel with this improvement of surface quality, the side surface of the diamond coating was modified to include nano-textures via the LIPSS (Laser Induced Periodic Surface Structuring) process. Through the fine piercing process, this nanotexture was transcribed onto the pierced hole surface together with fine shearing of the hole by piercing. WLI (White-Light Interferometry) and SEM (Scanning Electron Microscopy) were utilized to describe this transcription of nanotextures during the piercing process. These semi-regular nanotextures with an LIPSS period of 300 nm on the pierced hole surface induced a blue colored surface plasmon.
关键词： diamond-coated WC (Co) punch,concurrent transcription of nanotextures,surface plasmon,simultaneous nanotexturing,femtosecond laser trimming,fine piercing
更新于2025-09-23 15:21:01
-
Non-flipping <sup>13</sup> C spins near an NV center in diamond: hyperfine and spatial characteristics by density functional theory simulation of the C <sub/>510</sub> [NV]H <sub/>252</sub> cluster
摘要： Single NV centers in diamond coupled by hyperfine interaction (hfi) to neighboring 13C nuclear spins are now widely used in emerging quantum technologies as elements of quantum memory adjusted to a nitrogen-vacancy (NV) center electron spin qubit. For nuclear spins with low flip-flop rate, single shot readout was demonstrated under ambient conditions. Here we report on a systematic search for such stable NV?13C systems using density functional theory to simulate the hfi and spatial characteristics of all possible NV?13C complexes in the H-terminated cluster C510[NV]-H252 hosting the NV center. Along with the expected stable ‘NV-axial?13C’ systems wherein the 13C nuclear spin is located on the NV axis, we found for the first time new families of positions for the 13C nuclear spin exhibiting negligible hfi-induced flipping rates due to near-symmetric local spin density distribution. Spatially, these positions are located in the diamond bilayer passing through the vacancy of the NV center and being perpendicular to the NV axis. Analysis of available publications showed that, apparently, some of the predicted non-axial near-stable NV?13C systems have already been observed experimentally. A special experiment performed on one of these systems confirmed the prediction made.
关键词： density functional theory,diamond,NV centers
更新于2025-09-23 15:21:01
-
Switchable Complementary Diamond-ring-shaped Metasurface for Radome Application
摘要： Microwave radomes exhibiting bandpass behavior are highly desirable for antenna systems. However, most of these radomes are not frequency switchable owing to their fixed structures. Here, a switchable metasurface based on complementary diamond-ring-shaped resonators is proposed for radomes. The microwave properties of the metasurface are investigated via simulations and experiments at X-band. By adjusting the rotation angle θ from 0° to 90°, the bandpass frequency is switched from 11.0 GHz to 9.4 GHz. Two passbands appear for 0° < θ < 90°. In addition, the bandwidth can also be tuned by adjusting the rotation angle. This approach paves the way for designing switchable microwave radomes.
关键词： Switchable,Complementary diamond-ring-shaped resonator,Radomes,Metasurfaces
更新于2025-09-23 15:21:01
-
Fluorescent Nanodiamonds || Color Centers in Diamond
摘要： In this chapter, we will discuss the key features of nanodiamonds that are relevant to the development of fluorescent nanodiamonds (FNDs) and their many uses in biotechnology and beyond. Up till now, we have surveyed nanotechnology in previous chapters starting with its historical development and focusing, in particular, on the nanocarbon materials. With a general introduction to nanodiamonds (Chapter 2), we have learned some methods commonly used to prepare man‐made diamonds and the fundamental properties shared by all diamonds and nanodiamonds alike. In this and the following two chapters, we are about to find out that nanodiamonds can glow (Chapter 3), support (Chapter 4), and is safe to use (Chapter 5). These unique features have made nanodiamonds a superior material for a fast‐growing list of applications at present time and in the coming future.
关键词： biotechnology,fluorescent nanodiamonds,diamond,nanodiamonds,color centers
更新于2025-09-23 15:21:01