Nanocrystalline Diamond Films Prepared with Different Diamond Seeding Processes of 4 Nm and 0.25 Μm Diamond Powders

2014 ◽  
Vol 802 ◽  
pp. 146-151
Author(s):  
Marta Santos ◽  
R.A. Campos ◽  
A.F. Azevedo ◽  
M.R. Baldan ◽  
N.G. Ferreira
Keyword(s):  
Morphological Analysis ◽  
Diamond Particle ◽  
Diamond Films ◽  
Nucleation And Growth ◽  
Nucleation Density ◽  
Nucleation Process ◽  
Raman Scattering Spectroscopy ◽  
Metastable Condition ◽  
Diamond Powders

The growth of diamond films in metastable condition occurs in two steps: nucleation and growth of crystals. Studies have shown that the nucleation process is the most critical step and essential to optimize the properties of the diamond, but its understanding is still very limited. Furthermore, the nucleation process is directly related to the pretreatment applied to the surface of the substrate: cleaning the surface and seeding. When the substrate is silicon, it is cleaned with acetone and scratching with diamond particles dispersed in a suitable solvent followed by ultrasonic agitation (nucleation rate = 109part/cm2). However, research has demonstrated that the use of diamond nanoparticles (ND) prepared with the use of a powerful ultrasound (750W) provides nucleation density much higher (1012part/cm2) compared to that processed with larger size particles. This work demonstrates that diamond films prepared with ND different solutions exhibit differences in relation to diamond films prepared using diamond particle dispersed in an organic solvent. Morphological analysis and the quality of the films were evaluated by Scanning Electron Microscopy, Optical Perfilometry and Raman Scattering Spectroscopy.

Kinetic Monte Carlo Simulation of Impurity Effects on Nucleation and Growth of SiC Clusters on Si(100)

2013 ◽  
Vol 740-742 ◽  
pp. 393-396
Author(s):  
Maxim N. Lubov ◽  
Jörg Pezoldt ◽  
Yuri V. Trushin
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Cluster Size ◽  
Kinetic Monte Carlo ◽  
Nucleation And Growth ◽  
Nucleation Density ◽  
Nucleation Process ◽  
Impurity Effects ◽  
Kinetic Monte Carlo Simulations ◽  
The Mean

The influence of attractive and repulsive impurities on the nucleation process of the SiC clusters on Si(100) surface was investigated. Kinetic Monte Carlo simulations of the SiC clusters growth show that that increase of the impurity concentration (both attractive and repulsive) leads to decrease of the mean cluster size and rise of the nucleation density of the clusters.

Particle-Assisted Oriented Deposition of Diamond Thin Films

1996 ◽  
Vol 423 ◽  
Author(s):  
Dong-Gu Lee ◽  
Rajiv K. Singh
Keyword(s):  
Vapor Deposition ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
X Ray ◽  
Diamond Particles ◽  
Film Synthesis ◽  
Diamond Powders ◽  
Hot Filament

AbstractWe have developed a method for <111> oriented diamond film synthesis using micron-sized diamond particles. Different size of diamond powders were electrophoretically seeded on silicon substrates using diamond suspensions in organic solvents (acetone, methanol, and ethanol). Diamond suspension in acetone was found to be the best for obtaining uniform diamond seeding by electrophoresis. The thickness of diamond seeded films was changed by varying the applied voltage to observe the effect on the orientation of diamond particles. Then diamond films were deposited by the hot filament chemical vapor deposition (HFCVD) process. A preferred orientation with <111> direction normal to the substrate was obtained for monolayer coatings. The surface morphology, crystal orientation, and quality of diamond films were investigated using scanning electron microscopy, x-ray diffractometry, and Raman spectroscopy.

Realization Of X-Ray Lithography Masks Based On Diamond Membranes

1993 ◽  
Vol 306 ◽  
Author(s):  
M. F. Ravet ◽  
A. Gicquel ◽  
E. Anger ◽  
Z. Z. Wang ◽  
Y. Chen ◽  
...  
Keyword(s):  
Microwave Plasma ◽  
Plasma Reactor ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Nucleation And Growth ◽  
Local Conditions ◽  
X Ray ◽  
Deposition Parameters ◽  
Deposition Conditions

AbstractDeposition parameters acting on nucleation and growth local conditions have been optimized in a bell jar microwave plasma reactor to obtain polycrystalline diamond thin films compatible with X-ray membrane requests. The microstructure and the chemical quality of the films were estimated by SEM and Raman spectroscopy respectively, the roughness was evaluated by AFM experiments and the residual stress was deduced from the substrate deflection method. Membranes were obtained by removing the silicon substrate on 15 mm diameter circular windows. The optical transparency depending on deposition conditions was optimized up to 65% at 630 nm for 1 μm thickness. A high resolution additive mask process, based on well taut membranes and low stress electroplated gold absorber, was carried out. Micrometric and submicrometric mask patterns were generated in photoresists both by electron beam lithography with a nanopattern generator and by X-ray lithography using the synchrotron radiation facility implemented at LURE-Orsay. Despite the diamond films roughness of the order of 30 nm, well defined dots and lines as narrow as 100–200 nm could be obtained.

Characterization of homoepitaxial diamond films by Electron microscopy

1991 ◽  
Vol 49 ◽  
pp. 880-881
Author(s):  
D.P. Malta ◽  
S.A. Willard ◽  
R.A. Rudder ◽  
G.C. Hudson ◽  
J.B. Posthill ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Surface Defects ◽  
Substrate Surface ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Large Degree ◽  
Rf Plasma ◽  
Semiconducting Diamond

Semiconducting diamond films have the potential for use as a material in which to build active electronic devices capable of operating at high temperatures or in high radiation environments. A major goal of current device-related diamond research is to achieve a high quality epitaxial film on an inexpensive, readily available, non-native substrate. One step in the process of achieving this goal is understanding the nucleation and growth processes of diamond films on diamond substrates. Electron microscopy has already proven invaluable for assessing polycrystalline diamond films grown on nonnative surfaces.The quality of the grown diamond film depends on several factors, one of which is the quality of the diamond substrate. Substrates commercially available today have often been found to have scratched surfaces resulting from the polishing process (Fig. 1a). Electron beam-induced current (EBIC) imaging shows that electrically active sub-surface defects can be present to a large degree (Fig. 1c). Growth of homoepitaxial diamond films by rf plasma-enhanced chemical vapor deposition (PECVD) has been found to planarize the scratched substrate surface (Fig. 1b).

scholarly journals Optical Monitoring of the Production Quality of Si-Nanoribbon Chips Intended for the Detection of ASD-Associated Oligonucleotides

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 147
Author(s):  
Kristina A. Malsagova ◽  
Tatyana O. Pleshakova ◽  
Vladimir P. Popov ◽  
Igor N. Kupriyanov ◽  
Rafael A. Galiullin ◽  
...  
Keyword(s):  
Production Quality ◽  
Autism Spectrum ◽  
Covalent Immobilization ◽  
Biological Macromolecules ◽  
Label Free ◽  
Raman Scattering Spectroscopy ◽  
Dna Oligonucleotides ◽  
Highly Sensitive ◽  
Highly Sensitive Detection

Gas-phase etching and optical lithography were employed for the fabrication of a silicon nanoribbon chip (Si-NR chip). The quality of the so-fabricated silicon nanoribbons (Si-NRs) was monitored by optical Raman scattering spectroscopy. It was demonstrated that the structures of the Si-NRs were virtually defect-free, meaning they could be used for highly sensitive detection of biological macromolecules. The Si-NR chips were then used for the highly sensitive nanoelectronics detection of DNA oligonucleotides (oDNAs), which represent synthetic analogs of 106a-5p microRNA (miR-106a-5p), associated with the development of autism spectrum disorders in children. The specificity of the analysis was attained by the sensitization of the Si-NR chip sur-face by covalent immobilization of oDNA probes, whose nucleotide sequence was complementary to the known sequence of miR-106a-5p. The use of the Si-NR chip was demonstrated to al-low for the rapid label-free real-time detection of oDNA at ultra-low (~10−17 M) concentrations.

Nucleation and growth of diamond films on single crystal and polycrystalline tungsten substrates

2000 ◽  
Vol 9 (3-6) ◽  
pp. 262-268 ◽  
Author(s):  
Michael D. Whitfield ◽  
James A. Savage ◽  
Richard B. Jackman
Keyword(s):  
Single Crystal ◽  
Diamond Films ◽  
Nucleation And Growth ◽  
Polycrystalline Tungsten

Investigation on the Machining of Thick Diamond Films by EDM Together with Mechanical Polishing

2007 ◽  
Vol 24-25 ◽  
pp. 377-382
Author(s):  
Rong Fa Chen ◽  
Dun Wen Zuo ◽  
Yu Li Sun ◽  
Wen Zhuang Lu ◽  
D.S. Li ◽  
...  
Keyword(s):  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Mechanical Polishing ◽  
Polishing Process ◽  
Two Stage ◽  
Efficient Manner ◽  
Raman Scattering Spectroscopy ◽  
Electro Discharge Machining ◽  
Diamond Polishing ◽  
Cost Efficient

Although research on various diamond polishing techniques has been carried for years, some issues still need to be examined in order to facilitate application on large areas in a cost-efficient manner. A compositive technique for machining efficiently thick diamond films prepared by DC plasma arc jet is reported in the present paper. A two-stage polishing was applied on thick polycrystalline diamond films, by employing first electro-discharge machining (EDM) for rough polishing and subsequently mechanical polishing for finishing operations. Experimental results obtained clearly indicate the applicability of the proposed two-stage technique for fabricating transparent diamond films that can be used for the production of X-ray windows. Appropriate etching with EDM is an effective pretreatment method for enhancing the efficiency of rough polishing process in mechanical polishing of thick diamond film. The machined surfaces of diamond films are studied by Scanning Electron Microscope (SEM) and Raman Scattering Spectroscopy (Raman).

scholarly journals The Transformation from (111) to (100): A Routine to Large-Scale Epitaxial Diamond

2020 ◽  
Author(s):  
Yang Wang ◽  
Weihua Wang ◽  
Shilin Yang ◽  
Jiaqi Zhu
Keyword(s):  
Large Scale ◽  
Diamond Films ◽  
Diamond Growth ◽  
Nucleation Density ◽  
Diamond Synthesis ◽  
First Principle ◽  
High Quality ◽  
First Principle Calculations ◽  
Large Size ◽  
Experimental Researches

Diamond is a material with excellent performances which attracts the attention from researchers for decades. Pt (111), owing to its catalytic activity on diamond synthesis, is regarded to be a candidate for diamond hetero-epitaxity, which can enhance nucleation density. Molten surface at diamond growth temperature can also improve mobility and aggregation capability of primitive nuclei. Generally, (100)-oriented is welcomed for the achivement of high quality and large size diamond, since the formation of defects and twins are prevented. First-principle calculations and experimental researches were carried out for the study of transformation of orientation. The transformation from {111} to {100}-oriented diamond has been observed on Pt (111) substrate, which can be promoted by the increase of carbon source concentration and substrate temperature. The process is energetic favorable, which may provides a way towards large-scale (100) diamond films.

scholarly journals THE STUDY OF THE FROUD CRITERION INFLUENCE UPON THE QUALITY OF THE PRODUCTS FROZEN BY FLUIDIZATION

1970 ◽  
Vol 63 ◽  
Author(s):  
Mihaela Gabriela Chirila ◽  
I. Tofan
Keyword(s):  
Ice Crystals ◽  
Nucleation Process

The quality of the granular products frozen by fluidization depends on the structure of ice crystals. These are formed during the nucleation process. One of the factors which influence the nucleation process is Froude’s criterion.

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