scholarly journals Simulation-Based Development of a New Cylindrical-Cavity Microwave-Plasma Reactor for Diamond-Film Synthesis

Crystals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 320 ◽  
Author(s):  
Qijun Wang ◽  
Gai Wu ◽  
Sheng Liu ◽  
Zhiyin Gan ◽  
Bo Yang ◽  
...  
Keyword(s):  
Cylindrical Cavity ◽  
Microwave Plasma ◽  
Plasma Reactor ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Optical Microscope ◽  
Plasma Chemical Vapor Deposition ◽  
Atomic Force ◽  
Single Crystal Diamond ◽  
Film Synthesis

A 2.45 GHz microwave-plasma chemical-vapor deposition (MPCVD) reactor was designed and built in-house by collaborating with Guangdong TrueOne Semiconductor Technology Co., Ltd. A cylindrical cavity was designed as the deposition chamber and a circumferential coaxial-mode transformer located at the top of the cavity was adopted as the antenna. Two quartz-ring windows that were placed far away from the plasma and cooled by water-cooling cavity walls were used to affix the antenna to the cavity and act as a vacuum seal for the reactor, respectively. This design improved the sealing and protected the quartz windows. In addition, a numerical simulation was proposed to predict the electric-field and plasma-density distributions in the cavity. Based on the simulation results, a microwave-plasma reactor with TM021 mode was built. The leak rate of this new reactor was tested to be as low as 1 × 10−8 Pa·m3·s−1, and the maximal microwave power was as high as 10 kW. Then, single-crystal diamond films were grown with the morphology and crystalline quality characterized by an optical microscope, atomic force microscope (AFM), Raman spectrometer, photoluminescence (PL) spectrometer, and high-resolution X-ray diffractometer. It was shown that the newly developed MPCVD reactor can produce diamond films with high quality and purity.

scholarly journals Damage-free highly efficient plasma-assisted polishing of a 20-mm square large mosaic single crystal diamond substrate

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Nian Liu ◽  
Kohki Sugawara ◽  
Naoya Yoshitaka ◽  
Hideaki Yamada ◽  
Daisuke Takeuchi ◽  
...  
Keyword(s):  
Single Crystal ◽  
Microwave Plasma ◽  
Removal Rate ◽  
Chemical Vapor ◽  
Plasma Chemical Vapor Deposition ◽  
Highly Efficient ◽  
Atomic Force ◽  
Diamond Substrate ◽  
Single Crystal Diamond ◽  
Measurement Results

Abstract Plasma-assisted polishing (PAP) as a damage-free and highly efficient polishing technique has been widely applied to difficult-to-machine wide-gap semiconductor materials such as 4H-SiC (0001) and GaN (0001). In this study, a 20-mm square large mosaic single crystal diamond (SCD) substrate synthesized by microwave plasma chemical vapor deposition (CVD) was polished by PAP. Argon-based plasma containing oxygen was used in PAP to modify the surface of quartz glass polishing plate, and a high material removal rate (MRR) of 13.3 μm/h was obtained. The flatness of SCD polished by PAP measured by an interferometer was 0.5 μm. The surface roughness measured by both scanning white light interferometer (SWLI) (84-μm square) and atomic force microscope (AFM) (5-μm square) was less than 0.5 nm Sq. The micro-Raman spectroscopy measurement results of mosaic SCD substrate processed by PAP showed that residual stress and non-diamond components on the surface after PAP processing were below the detection limit.

scholarly journals Synthesis of ultrasmooth nanostructured diamond films by microwave plasma chemical vapor deposition using a He/H2/CH4/N2gas mixture

2006 ◽  
Vol 21 (10) ◽  
pp. 2675-2682 ◽  
Author(s):  
S. Chowdhury ◽  
Damon A. Hillman ◽  
Shane A. Catledge ◽  
Valery V. Konovalov ◽  
Yogesh K. Vohra
Keyword(s):  
Gas Flow ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Optical Emission ◽  
X Ray Diffraction ◽  
Plasma Chemical Vapor Deposition ◽  
Force Microscopy ◽  
Atomic Force ◽  
Gas Flow Ratio

Ultrasmooth nanostructured diamond (USND) films were synthesized on Ti–6Al–4V medical grade substrates by adding helium in H2/CH4/N2plasma and changing the N2/CH4gas flow from 0 to 0.6. We were able to deposit diamond films as smooth as 6 nm (root-mean-square), as measured by an atomic force microscopy (AFM) scan area of 2 μm2. Grain size was 4–5 nm at 71% He in (H2+ He) and N2/CH4gas flow ratio of 0.4 without deteriorating the hardness (∼50–60 GPa). The characterization of the films was performed with AFM, scanning electron microscopy, x-ray diffraction (XRD), Raman spectroscopy, and nanoindentation techniques. XRD and Raman results showed the nanocrystalline nature of the diamond films. The plasma species during deposition were monitored by optical emission spectroscopy. With increasing N2/CH4feedgas ratio (CH4was fixed) in He/H2/CH4/N2plasma, a substantial increase of CN radical (normalized by Balmer Hαline) was observed along with a drop in surface roughness up to a critical N2/CH4ratio of 0.4. The CN radical concentration in the plasma was thus correlated to the formation of ultrasmooth nanostructured diamond films.

scholarly journals Fabrication of a Micron-Scale Three-Dimensional Single Crystal Diamond Channel Using a Micro-Jet Water-Assisted Laser

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3006
Author(s):  
Qiang Wei ◽  
Xiaofan Zhang ◽  
Fang Lin ◽  
Ruozheng Wang ◽  
Genqiang Chen ◽  
...  
Keyword(s):  
Single Crystal ◽  
Cross Sections ◽  
Microwave Plasma ◽  
Three Dimensional ◽  
Chemical Vapor ◽  
Optical Microscope ◽  
Epitaxial Lateral Overgrowth ◽  
Plasma Chemical Vapor Deposition ◽  
Lateral Overgrowth ◽  
Single Crystal Diamond

Two types of a trench with conventional vertical and new reverse-V-shaped cross-sections were fabricated on single crystal diamond (SCD) substrate using a micro-jet water-assisted laser. In addition, a microwave plasma chemical vapor deposition device was used to produce multiple micrometer-sized channels using the epitaxial lateral overgrowth technique. Raman and SEM methods were applied to analyze both types of growth layer characterization. The hollowness of the microchannels was measured using an optical microscope. According to the findings, the epitaxial lateral overgrowth layer of the novel reverse-V-shaped trench produced improved SCD surface morphology and crystal quality.

scholarly journals Fabrication of Micron Scale Three-Dimensional Single Crystal Diamond Channel: by Micro-Jet Water-Assist Laser

2021 ◽  
Author(s):  
Qiang Wei ◽  
Xiaofan Zhang ◽  
Fang Lin ◽  
Ruozheng Wang ◽  
Genqiang Chen ◽  
...  
Keyword(s):  
Microwave Plasma ◽  
Three Dimensional ◽  
Chemical Vapor ◽  
Optical Microscope ◽  
Epitaxial Lateral Overgrowth ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
Lateral Overgrowth ◽  
Single Crystal Diamond ◽  
Micrometer Size

Two types of trenches cross-section in conventional vertical and brand new reverse-V-shape have fabricated on SCD substrate by micro-jet water-assist laser, the epitaxial lateral overgrowth technique has applied by microwave plasma chemical vapor deposition system in forming multiple micrometer-size channels. Raman and SEM techniques have applied in analyze both types growth layer characterization. Optical microscope has used to test microchannels hollowness. As a result, with the brand new reverse-V-shape trench, epitaxial lateral overgrowth layer reaches higher SCD surface morphology and crystal quality.

scholarly journals Evolution of High-Quality Homoepitaxial CVD Diamond Films Induced by Methane Concentration

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 888
Author(s):  
Pengfei Zhang ◽  
Weidong Chen ◽  
Longhui Zhang ◽  
Shi He ◽  
Hongxing Wang ◽  
...  
Keyword(s):  
Methane Concentration ◽  
Flat Surface ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Plasma Chemical ◽  
High Quality ◽  
Effect Analysis ◽  
Plasma Chemical Vapor Deposition ◽  
Atomically Flat

In this paper, we successfully synthesized homoepitaxial diamond with high quality and atomically flat surface by microwave plasma chemical vapor deposition. The sample presents a growth rate of 3 μm/h, the lowest RMS of 0.573 nm, and the narrowest XRD FWHM of 31.32 arcsec. An effect analysis was also applied to discuss the influence of methane concentration on the diamond substrates.

Nano-Crystalline Diamond Films Deposited on Copper Substrate by MPCVD Method

2011 ◽  
Vol 117-119 ◽  
pp. 1310-1314
Author(s):  
Xing Rui Li ◽  
Xin Wei Shi ◽  
Ning Yao ◽  
Xin Chang Wang
Keyword(s):  
Diamond Film ◽  
Deposition Time ◽  
Microwave Plasma ◽  
Copper Substrate ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Annealing Process ◽  
Adhesive Properties ◽  
Plasma Chemical Vapor Deposition ◽  
Nano Crystalline

Nano-crystalline diamond (NCD) films with good adhesion were deposited on flexible copper substrate with Ni interlayer by Microwave Plasma Chemical Vapor Deposition (MPCVD). In this paper, two-stage method was used to improve the adhesion between the copper substrates and the diamond films. The effect of deposition time of the first stage on the morphology, crystal structure, non-diamond phase and adhesive properties of diamond films was investigated. The performance and structure of the diamond films were studied by Scanning Electron Microscope (SEM), Raman Spectroscopy (Raman) and X-Ray Diffraction (XRD). The results showed that the films were nano-crystalline diamond films positively. Impress method was used to examine the adhesion between diamond film and the substrate. When deposition time is 1.5h, the adhesion between diamond film and the copper substrate is better than the others. When it was 2.5h or longer, because the graphite layers existed as intermediate, the adherence between the diamond films and copper substrates was very poor. Therefore, the diamond films were easily peeled off from the substrates. Otherwise, the second stage called annealing process after the deposition played an important role to the adhesion. The films would be easily peeled off by curling without the annealing process.

Overgrowth of Single Crystal Diamond Using Defect-Selective Etching and Epitaxy Technique in Chemical Vapor Deposition

2021 ◽  
Vol 21 (8) ◽  
pp. 4412-4417
Author(s):  
Jonggeon Lee ◽  
Taemyung Kwak ◽  
Geunho Yoo ◽  
Seongwoo Kim ◽  
Okhyun Nam
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Defect Density ◽  
Chemical Vapor ◽  
Atomic Force Microscope Image ◽  
Selective Etching ◽  
Diamond Surface ◽  
Plasma Chemical Vapor Deposition ◽  
Single Crystal Diamond

In this study, we demonstrated the defect-selective etching and epitaxy technique for defect reduction of a heteroepitaxial chemical vapor deposition (CVD) diamond substrate. First, an 8 nm layer of nickel was deposited on the diamond surface using an e-beam evaporator. Then, defect-selective etching was conducted through an in situ single process using microwave plasma chemical vapor deposition (MPCVD). After defect-selective etching, the diamond layer was overgrown by MPCVD. The defect density measured from the atomic force microscope image decreased from 3.27×108 to 2.02×108 cm−2. The first-order Raman peak of diamond shifted from 1340 to 1336 cm−1, and the full width at half maximum (FWHM) decreased from 9.66 to 7.66 cm−1. Through the defect-selective etching and epitaxy technique, it was confirmed that the compressive stress was reduced and the crystal quality improved.

Lateral outward growth of single-crystal diamond by two different structures of microwave plasma reactors

CrystEngComm ◽  
2022 ◽  
Author(s):  
Wei Cao ◽  
Zhibin Ma ◽  
Hongyang Zhao ◽  
Deng Gao ◽  
Qiuming Fu
Keyword(s):  
Chemical Vapor Deposition ◽  
Single Crystal ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Lateral Growth ◽  
Plasma Reactors ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
Single Crystal Diamond

On a semi-open holder, the homoepitaxial lateral growth of single-crystal diamond (SCD) was carried out via microwave plasma chemical vapor deposition (MPCVD). By tuning and optimizing two different structures of...

Sign in / Sign up

Export Citation Format

Share Document