Structural and Morphological Characterization of 3C-SiC Films Grown on (111), (211) and (100) Silicon Substrates

2008 ◽  
Vol 600-603 ◽  
pp. 231-234 ◽  
Author(s):  
Marc Portail ◽  
M. Nemoz ◽  
Marcin Zielinski ◽  
Thierry Chassagne
Keyword(s):  
Flow Rate ◽  
Morphological Characterization ◽  
Crystalline Quality ◽  
Silicon Substrates ◽  
Interfacial Defects ◽  
Twin Defects ◽  
Sic Films

The structural and morphological modifications induced by the carbonization stage upon 3C-SiC heteroepitaxial films grown on (111) and (100) oriented silicon substrates have been investigated. The crystalline quality of the films is strongly dependent on the carbonization parameters (propane flow rate and duration of carbonization). The (111) heteroepitaxial films coalesce more rapidly and present a lower dependence on the carbonization conditions than (100) films. By comparing the evolution of the interfacial defects (voids) density with existing models, we show that this is related to the initial mechanisms occurring during the carbonization stage. The twin defects densities on (111), (100) and (211) films are also investigated and the role of the only carbonization stage on their formation is studied.

scholarly journals Magnetic characterization of (001) and (111) Ni films epitaxially grown on MgO

2001 ◽  
Vol 674 ◽  
Author(s):  
R. A. Lukaszew ◽  
V. Stoica ◽  
R. Clarke
Keyword(s):  
Film Growth ◽  
Chemical Interaction ◽  
Hysteresis Loops ◽  
Magnetic Thin Films ◽  
Magnetic Films ◽  
Buffer Layers ◽  
Crystalline Quality ◽  
Silicon Substrates

ABSTRACTOne interesting application of epitaxial magnetic thin films is to use them as one of the electrodes in a spin-dependent tunneling junction, in order to use the magnetocrystalline anisotropy to define the required two states of the magnetization. [1] In our preliminary work, we prepared epitaxial magnetic films on copper buffer layers grown on silicon substrates. [2] The single crystalline quality of the films was particularly evident in the magnetization hysteresis loops, showing a sharp reversal at fairly high fields (120 Oe), when the samples were magnetized along the crystallographic easy axis. One technological disadvantage in this type of samples is the chemical interaction between the metallic layers and the silicon substrate.In order to explore the possibility of epitaxial magnetic films on less reactive substrates, we studied the growth on MgO substrates. We have shown that it is possible to obtain epitaxial (001) and (111) Ni films grown on MgO substrates. [3] In particular we observed that the crystalline quality of the films improved considerably after 10 nm of film growth. We will now present our studies on the magnetic properties of these films, particularly the azimuthal dependence of the magnetization reversal using MOKRE, correlating our finding with the structural characterization obtained with RHEED, STM and XRD.

Effect of Propane on Low Temperature Growth of 3C-SiC Film on Si (111) by Plasma Assisted CVD

2012 ◽  
Vol 717-720 ◽  
pp. 181-184
Author(s):  
Hideki Shimizu ◽  
Takashi Watanabe
Keyword(s):  
Substrate Temperature ◽  
Flow Rate ◽  
Crystalline Quality ◽  
X Ray Diffraction ◽  
Temperature Growth ◽  
Transmission Electron ◽  
Good Crystalline Quality ◽  
Sic Film ◽  
Sic Films

To demonstrate the formation of 3C-SiC film on Si (111) at low substrate temperature, the effects of C3H8 on the crystalline quality of the 3C-SiC films on Si (111) have been investigated by changing the flow rate of C3H8 at the substrate temperature of 950 °C. The crystalline quality has been investigated by transmission electron microscope and X-ray diffraction. 3C-SiC is epitaxially grown on Si(111) and the 3C-SiC films are in either near single crystalline or highly oriented form with stacking faults and twin. It is expected that the film with good crystalline quality may grow at around 2.5 in the ratio of the flow rate of C3H8 to SiH4 and any microstructures of 3C-SiC films on Si (111) can be controlled by accurately controlling the ratio of C/Si.

scholarly journals Gut microbiota profiles and characterization of cultivable fungal isolates in IBS patients

2021 ◽  
Author(s):  
Piero Sciavilla ◽  
Francesco Strati ◽  
Monica Di Paola ◽  
Monica Modesto ◽  
Francesco Vitali ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Gut Microbiota ◽  
Healthy Subjects ◽  
Fungal Isolates ◽  
Key Points ◽  
Health Promoting ◽  
Irritable Bowel

Abstract Studies so far conducted on irritable bowel syndrome (IBS) have been focused mainly on the role of gut bacterial dysbiosis in modulating the intestinal permeability, inflammation, and motility, with consequences on the quality of life. Limited evidences showed a potential involvement of gut fungal communities. Here, the gut bacterial and fungal microbiota of a cohort of IBS patients have been characterized and compared with that of healthy subjects (HS). The IBS microbial community structure differed significantly compared to HS. In particular, we observed an enrichment of bacterial taxa involved in gut inflammation, such as Enterobacteriaceae, Streptococcus, Fusobacteria, Gemella, and Rothia, as well as depletion of health-promoting bacterial genera, such as Roseburia and Faecalibacterium. Gut microbial profiles in IBS patients differed also in accordance with constipation. Sequence analysis of the gut mycobiota showed enrichment of Saccharomycetes in IBS. Culturomics analysis of fungal isolates from feces showed enrichment of Candida spp. displaying from IBS a clonal expansion and a distinct genotypic profiles and different phenotypical features when compared to HS of Candida albicans isolates. Alongside the well-characterized gut bacterial dysbiosis in IBS, this study shed light on a yet poorly explored fungal component of the intestinal ecosystem, the gut mycobiota. Our results showed a differential fungal community in IBS compared to HS, suggesting potential for new insights on the involvement of the gut mycobiota in IBS. Key points • Comparison of gut microbiota and mycobiota between IBS and healthy subjects • Investigation of cultivable fungi in IBS and healthy subjects • Candida albicans isolates result more virulent in IBS subjects compared to healthy subjects

Bentonite-Based Organoclays as Innovative Flame Retardants Agents for SBS Copolymer

2008 ◽  
Vol 8 (12) ◽  
pp. 6316-6324 ◽  
Author(s):  
M. Comes Franchini ◽  
P. Fabbri ◽  
A. Frache ◽  
G. Ori ◽  
M. Messori ◽  
...  
Keyword(s):  
Flame Retardants ◽  
Morphological Characterization ◽  
Tem Analysis ◽  
Important Functional Property ◽  
Octadecyltrimethylammonium Bromide ◽  
Nitrogen Containing Compounds ◽  
Styrene Butadiene ◽  
Heat Released

Two organophilic bentonites, based on nitrogen-containing compounds, have been synthesised via ion exchange starting from pristine bentonite with octadecyltrimethylammonium bromide (OTAB) and with synthetic melamine-derived N2,N4-dihexadecyl-1,3,5-triazine-2,4,6-triamine (DEDMEL). The chemical and morphological characterization of the organoclays was based on XRD, TEM, Laser Granulometry, X-Ray Fluorescence and CEC capacity. Copoly(styrene-butadiene-styrene)-nanocomposites (SBS-nanocomposites) were obtained by intercalation of the SBS-copolymer into these new organoclays by melt intercalation method. XRD and TEM analysis of the organoclays and of the micro/nano-composites obtained are presented. The effect of the organoclays on the SBS-nanocomposite's flammability properties was investigated using cone calorimeter. An encouraging decrease of 20% in the peak heat released rate (PHRR) has been obtained confirming the important role of melamine's based skeleton and its derived organoclays to act as effective fire retardants and for the improvement of this important functional property in SBS copolymers.

Hetero-Epitaxial Growth of 3C-SiC on Silicon Substrates by Plasma Assisted CVD

2006 ◽  
Vol 527-529 ◽  
pp. 299-302
Author(s):  
Hideki Shimizu ◽  
Yosuke Aoyama
Keyword(s):  
Substrate Temperature ◽  
Single Crystal ◽  
Epitaxial Growth ◽  
Deposition Rate ◽  
Crystalline Structure ◽  
Flow Rate ◽  
Silicon Substrates ◽  
High Quality ◽  
Sic Films ◽  
Lower Substrate Temperature

3C-SiC films grown on carbonized Si (100) by plasma-assisted CVD have been investigated with systematic changes in flow rate of monosilane (SiH4) and propane (C3H8) as source gases. The deposition rate of the films increased monotonously and the microstructures of the films changed from 3C-SiC single crystal to 3C-SiC polycrystal with increasing flow rate of SiH4. Increasing C3H8 keeps single crystalline structure but results in contamination of α-W2C, which is a serious problem for the epitaxial growth. To obtain high quality 3C-SiC films, the effects of C3H8 on the microstructures of the films have been investigated by reducing the concentration of C3H8. Good quality 3C-SiC single crystal on Si (100) is grown at low net flow rate of C3H8 and SiH4, while 3C-SiC single crystal on Si (111) is grown at low net flow rate of C3H8 and high net flow rate of SiH4. It is expected that 3C-SiC epitaxial growth on Si (111) will take placed at a higher deposition rate and lower substrate temperature than that on Si (100).

Key Radicals for Hetero-Epitaxial Growth of 3C-SiC on Silicon Substrates

2005 ◽  
Vol 483-485 ◽  
pp. 209-212
Author(s):  
Hideki Shimizu ◽  
Kensaku Hisada ◽  
Yosuke Aoyama
Keyword(s):  
Epitaxial Growth ◽  
Flow Rate ◽  
Hydrogen Plasma ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Ellipsometric Measurement ◽  
X Ray ◽  
Hydrogen Radicals ◽  
Sic Films ◽  
Reflection Electron Diffraction

Effects of the flow rate of C3H8 passed through hydrogen plasma on deposition rates and^microstructures of 3C-SiC films on Si (100) substrate were investigated by a reflection electron diffraction, an X-ray diffraction and an ellipsometric measurement. The deposition rate of the films increased independently of the flow rate of C3H8 with increasing the flow rate of SiH4. The films grown with increasing the flow rate of C3H8 kept single crystalline structure even at high flow rate of SiH4. Hydrogen radicals generated from C3H8 decomposition by plasma increase with increasing the flow rate of C3H8, and play important rolls to keep epitaxial growth.

Electrical Characterization of Low Temperature PECVD Oxides for TSV Applications

2018 ◽  
Vol 2018 (1) ◽  
pp. 000728-000733
Author(s):  
Piotr Mackowiak ◽  
Rachid Abdallah ◽  
Martin Wilke ◽  
Jash Patel ◽  
Huma Ashraf ◽  
...  
Keyword(s):  
Low Temperature ◽  
Electrical Characterization ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
Low Temperature Plasma ◽  
Temperature Plasma ◽  
Charge Densities ◽  
Doped Silicon

Abstract In the present work we investigate the quality of low temperature Plasma Enhanced Chemical Vapor Deposition (PECVD) and plasma treated Tetraethyl orthosilicate (TEOS)-based TSV-liner films. Different designs of Trough Silicon Via (TSV) Test structures with 10μm and 20μm width and a depth of 100μm have been fabricated. Two differently doped silicon substrates have been used – highly p-doped and moderately doped. The results for break-through, resistivity and capacitance for the 20μm structures show a better performance compared to the 10μm structures. This is mainly due to increased liner thickness in the reduced aspect ratio case. Lower interface traps and oxide charge densities have been observed in the C-V measurements results for the 10μm structures.

Production and characterization of CZTS films: On the role of H2S flow rate

Solar Energy ◽  
2019 ◽  
Vol 194 ◽  
pp. 709-715
Author(s):  
Idris Akyuz ◽  
Ferhunde Atay ◽  
Remzi Aydin ◽  
Salih Kose
Keyword(s):  
Flow Rate
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