THE ABRASION RESISTANCE AND ADHESION OF HFCVD BORON AND SILICON-DOPED DIAMOND FILMS ON WC–Co DRAWING DIES

2017 ◽  
Vol 24 (07) ◽  
pp. 1750090 ◽  
Author(s):  
LIANG WANG ◽  
JINFEI LIU ◽  
TANG TANG ◽  
FANGHONG SUN ◽  
NAN XIE
Keyword(s):  
Adhesive Strength ◽  
Abrasion Resistance ◽  
Copper Wire ◽  
Diamond Films ◽  
Chemical Vapor ◽  
High Growth ◽  
Diamond Powder ◽  
Wire Drawing ◽  
High Growth Rate ◽  
Drawing Dies

Diamond films have been deposited on the interior hole surface of cobalt-cemented tungsten carbide (WC–Co) drawing dies from acetone, trimethyl borate (C3H9BO3), tetraethoxysilane (C8H[Formula: see text]O4Si, TEOS) and hydrogen mixture by hot-filament chemical vapor deposition (HFCVD) method. The structures and quality of as-deposited diamond films are characterized with field-emission scanning electron microscopy (FESEM) and Raman spectroscopy. The abrasion ratio and the adhesive strength of as-deposited diamond films are evaluated by copper wire drawing tests and ultrasonic lapping tests, respectively. The results suggest that diamond films with small grain size and high growth rate can be obtained due to the mutual effects of boron and silicon impurities in the gas phases. The results of ultrasonic lapping tests show that diamond films doped with boron and/or silicon can bear the severe erosion of the large diamond powder. Diamond films peeling off within the reduction zone of the drawing dies cannot be observed after testing of 2[Formula: see text]h. The abrasion ratio of boron and silicon-added diamond films is five times that of diamond films without any addition. Adding boron and/or silicon in the diamond films is proved to be an efficient way to obtain high-adhesive-strength and high-abrasion-resistance diamond-coated drawing dies.

Nitrogen and Bias Effect on Homoepitaxial Diamond Growth by Hot-Filament Chemical Vapor Deposition

2010 ◽  
Vol 443 ◽  
pp. 510-515 ◽  
Author(s):  
Hung Yin Tsai ◽  
Chih Cheng Chang ◽  
Chih Wei Wu
Keyword(s):  
Growth Rate ◽  
Chemical Vapor Deposition ◽  
Diamond Film ◽  
Vapor Deposition ◽  
Diamond Films ◽  
Chemical Vapor ◽  
High Growth ◽  
High Growth Rate ◽  
High Quality ◽  
Hot Filament

The development of homoepitaxial films for advanced device applications has been studied, but high growth rate and diamond film quality have not yet been explored. In the current study, high quality homoepitaxial diamond films were grown on type Ib (100) HPHT synthetic diamond substrate by hot-filament chemical vapor deposition. The reactant gases were mixed by CH4 and H2 with small amounts of N2 (500 to 3000 ppm). Besides, a bias system was used to assist diamond film deposition. The pyramidal crystals on diamond surface can be suppressed and high quality diamond film of FWHM (Full Width at Half Maximum) = 10.76 cm-1 with high growth rate of 8.78 ± 0.2 μm/ hr was obtained at the condition of adding 1000 ppm nitrogen. At the bias voltage of -150 V, the pyramidal crystals can also be suppressed and high quality diamond film of FWHM = 10.19 cm-1 was obtained. With nitrogen addition above 2000 ppm, diamond film was partly doped and some sp2 structures appeared. These homoepitaxial diamond films were characterized by optical microscopy and micro-Raman spectroscopy.

Deposition and Application of CVD Diamond Film on the Interior-Hole Surface of Shaped-Wire Drawing Die

2012 ◽  
Vol 217-219 ◽  
pp. 1022-1027
Author(s):  
Liu Jin Bian ◽  
Zi Chao Lin ◽  
Fang Hong Sun ◽  
Song Shou Guo
Keyword(s):  
Surface Quality ◽  
Diamond Film ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Cvd Diamond ◽  
Wire Drawing ◽  
Drawing Die ◽  
Before And After ◽  
Cvd Diamond Film ◽  
Drawing Dies

Abstract：The shaped-wire drawing dies are used more and more popularly in the metal product industry for several advantages of locked structure. In present investigation, a layer of CVD diamond film is deposited on the interior-hole surface of shaped-wire drawing die using a hot filament chemical vapor deposition (HFCVD) method, followed by a surface polishing process, aiming at further prolonging its working lifetime of shaped-wire drawing dies and improving the surface quality of produced wires. The scanning electron microscopy (SEM), surface profiler and Raman spectroscopy are adopted to present the characterization of both as-deposited CVD diamond films before and after polishing. Furthermore, the performance of as-fabricated CVD diamond coated drawing dies is examined in the practical production process. The results show that as-deposited CVD diamond films are homogeneous and the working surface is smoother after polishing. Comparing with the conventional shaped drawing dies, the working lifetime of the diamond coated shaped-wire drawing dies can be increased by a factor of above 10, and the shaped wires with higher surface quality can be obtained.

Mocvd SrS:Ce for Applications in Electroluminescent Devices

1997 ◽  
Vol 471 ◽  
Author(s):  
D. Endisch ◽  
K. Barth ◽  
J. Lau ◽  
G. Peterson ◽  
A. E. Kaloyeros ◽  
...  
Keyword(s):  
Process Development ◽  
Process Integration ◽  
Low Cost ◽  
Chemical Vapor ◽  
High Growth ◽  
Film Structure ◽  
High Growth Rate ◽  
Organic Chemical ◽  
Glass Substrates ◽  
Full Color

ABSTRACTSrS:Ce is an important material for full color electroluminescent (EL) flat panel displays. Using a combination of SrS:Ce/ZnS:Mn and appropriate color filters high quality full color displays have been demonstrated [1]. Major issues for commercially viable process integration of SrS:Ce are the combination of high luminance, high growth rate, and process temperatures below 600°C for compatibility with low cost glass substrates. This work describes the process development and optimization of metal-organic chemical vapor deposition (MOCVD) of SrS:Ce. MOCVD is a promising candidate for deposition of SrS:Ce because it can provide the required growth rates and allows control of crystal structure and stoichiometry. Growth of SrS:Ce was performed in the temperature range from 400°C to 530°C using Sr(tmhd)2, Ce(tmhd)4, and H2S as precursors. The structure of the SrS:Ce was found to be strongly dependent on the H2S flow. A brightness of 15 fL and an efficiency of 0.22 lm/W has been achieved (40 V above threshold voltage, 60 Hz AC). Film analysis included Rutherford backscattering (RBS), X-ray diffraction (XRD), atomic force microscopy (AFM), and EL measurements. Results on the correlation between process parameters, film structure, grain size and EL performance will be presented.

Guiding Principle to Develop Intrinsic Microcrystalline Silicon Absorber Layer For Solar Cell By Hot-Wire Cvd

2001 ◽  
Vol 664 ◽  
Author(s):  
A. R. Middya ◽  
U. Weber ◽  
C. Mukherjee ◽  
B. Schroeder
Keyword(s):  
Growth Rate ◽  
Solar Cell ◽  
Cell Structure ◽  
Short Circuit ◽  
Chemical Vapor ◽  
High Growth ◽  
High Growth Rate ◽  
Open Circuit ◽  
Hot Wire ◽  
Microcrystalline Silicon

ABSTRACTWe report on ways to develop device quality microcrystalline silicon (μc-Si:H) intrinsic layer with high growth rate by hot-wire chemical vapor deposition (HWCVD). With combine approach of controlling impurities and moderate H-dilution [H2/SiH4 ͌ 2.5], we developed, for the first time, highly photosensitive (103 μc-Si:Hfilms with high growth rate (>1 nm/s); the microstructure of the film is found to be close to amorphous phase (fc ͌ 46 ̻± 5%). The photosensitivity systematically decreases with fc and saturates to 10 for fc> 70%. On application of these materials in non-optimized pin [.proportional]c-Si:H solar cell structure yields 700 mV open-circuit voltage however, surprisingly low fill factor and short circuit current. The importance of reduction of oxygen impurities [O], adequate passivation of grain boundary (GB) as well as presence of inactive GB of (220) orientation to achieve efficient [.proportional]c-Si:H solar cells are discussed.

Halide-CVD Growth of Bulk SiC Crystals

2006 ◽  
Vol 527-529 ◽  
pp. 21-26 ◽  
Author(s):  
A.Y. Polyakov ◽  
Mark A. Fanton ◽  
Marek Skowronski ◽  
Hun Jae Chung ◽  
Saurav Nigam ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
High Growth ◽  
High Growth Rate ◽  
Flow Ratio ◽  
Novel Approach ◽  
Cvd Growth ◽  
Electron And Hole Traps ◽  
Separate Injection

A novel approach to the high growth rate Chemical Vapor Deposition of SiC is described. The Halide Chemical Vapor Deposition (HCVD) method uses SiCl4, C3H8 (or CH4), and hydrogen as reactants. The use of halogenated Si source and of separate injection of Si and C precursors allows for preheating of source gases without causing premature chemical reactions. The stoichiometry of HCVD crystals can be controlled by changing the C/Si flow ratio and can be kept constant throughout growth, in contrast to the Physical Vapor Transport technique. HCVD was demonstrated to deposit high crystalline quality, very high purity 4H- and 6H-SiC crystals with growth rates comparable to other bulk SiC growth techniques. The densities of deep electron and hole traps are determined by growth temperature and C/Si ratio and can be as low as that found in standard silane-based CVD epitaxy. At high C/Si flow ratio, the resistivity of HCVD crystals exceeds 105 _cm. These characteristics make HCVD an attractive method to grow SiC for applications in high-frequency and/or high voltage devices.

Morphological instabilities in the low pressure synthesis of diamond

1992 ◽  
Vol 7 (2) ◽  
pp. 384-393 ◽  
Author(s):  
K.V. Ravi
Keyword(s):  
Growth Rates ◽  
Diamond Films ◽  
High Growth ◽  
High Growth Rate ◽  
High Rate ◽  
Diamond Growth ◽  
Diamond Crystals ◽  
Pressure Synthesis ◽  
Morphological Instabilities ◽  
The Individual

Morphological instabilities attending the high growth rate of diamond films are examined. Pertinent literature on morphological instabilities and microstructure evolution in vapor deposited films is reviewed and theoretical treatments related to the case of diamond growth are discussed. Diamond films of various thicknesses have been synthesized utilizing the combustion flame synthesis technique involving diamond growth rates of ∼1 μm/min. Films of thicknesses under 20 μm are found to be dense and the surface smoothness of such films is governed by facets on the individual crystallites that make up the film. Increasing film thicknesses, at high growth rates, results in extremely rough surfaces, the trapping of voids and discontinuities, and the incorporation of non-diamond phases in the growing film. These characteristics are typical of morphological instabilities when surface diffusion and re-evaporation processes are absent and instability is promoted by the high rate arrival of the appropriate species from the flame ambient to the surface. Factors contributing to morphological instabilities include competitive shadowing and nutrient starvation and growth anisotropy of the different crystallographic faces on individual diamond crystals. It is shown that surface temperature and the presence of oxidizing species in the flame ambient contribute to anisotropic growth of diamond crystals and hence to morphological instabilities in diamond films. An approach to avoiding these instabilities is briefly discussed.

Laser direct writing of graphene patterns

2011 ◽  
Vol 1365 ◽  
Author(s):  
J.B. Park ◽  
W. Xiong ◽  
Z.Q. Xie ◽  
M. Mitchell ◽  
Y. Gao ◽  
...  
Keyword(s):  
Single Layer ◽  
Chemical Vapor ◽  
High Growth ◽  
High Growth Rate ◽  
Single Layer Graphene ◽  
Direct Writing ◽  
Optically Pumped ◽  
Scan Speed ◽  
Thin Nickel ◽  
532 Nm

ABSTRACTRapid growth of single-layer graphene using laser-induced chemical vapor deposition (LCVD) with a visible CW laser (λ = 532 nm) irradiation at room temperature was investigated. In this study, an optically-pumped solid-state laser with a wavelength of 532 nm irradiates a thin nickel foil to induce a local temperature rise, thereby allowing the direct writing of graphene patterns about ~10 μm in width with high growth rate on precisely controlled positions. It is demonstrated that the fabrication of graphene patterns can be achieved with a single scan for each graphene pattern using LCVD with no annealing or preprocessing of the substrate. The scan speed reaches to about ~50 um/s, which indicates that the graphene pattern with 1:1 aspect ratio (x:y) can be grown in 0.2 sec. The patterned graphene on nickel was transferred to SiO2/Si substrate for fabrication of electrical circuits and sensor devices.

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