• Title/Summary/Keyword: silicon Carbide

Search Result 748, Processing Time 0.025 seconds

Preperation of Silicon Carbide Oxidation Protection Film on Carbon Thermal Insulator Using Polycarbosilane and Its Characterization (폴리카보실란을 이용하여 탄소단열재에 코팅한 실리콘카바이드 코팅막의 내산화 특성)

  • Ahn, Su-Bin;Lee, Yoonjoo;Bang, Jung-Won;Shin, Dong-Geun;Kwon, Woo-Teck
    • Korean Journal of Materials Research
    • /
    • v.27 no.9
    • /
    • pp.471-476
    • /
    • 2017
  • In order to improve the high temperature oxidation resistance and lifespan of mat type porous carbon insulation, SiC was coated on carbon insulation by solution coating using polycarbosilane solution, curing in an oxidizing atmosphere at $200^{\circ}C$, and pyrolysis at temperatures up to $1200^{\circ}C$. The SiOC phase formed during the pyrolysis process was converted into SiC crystals as the heat treatment temperature increased, and a SiC coating with a thickness of 10-15 nm was formed at $1600^{\circ}C$. The SiC coated specimen showed a weight reduction of 8.6 % when it was kept in an atmospheric environment of $700^{\circ}C$ for 1 hour. On the other hand, the thermal conductivity was 0.17 W/mK, and no difference between states before and after coating was observed at all.

High-Quality Graphene Films Synthesized by Inductively-Coupled Plasma-Enhanced Chemical Vapor Deposition

  • Lam, Van Nang;Park, Nam-Kuy;Kim, Eui-Tae
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2012.05a
    • /
    • pp.90.2-90.2
    • /
    • 2012
  • Graphene has recently attracted significant attention because of its unique optical and electrical properties. For practical device applications, special attention has to be paid to the synthesis of high-quality graphene on large-area substrates. Graphene has been synthesized by eloborated mechanical exfoliation of highly oriented pyrolytic graphite, chemical reduction of exfoliated grahene oxide, thermal decomposition of silicon carbide, and chemical vapor deposition (CVD) on Ni or Cu substrates. Among these techniques, CVD is superior to the others from the perspective of technological applications because of its possibility to produce a large size graphene. PECVD has been demonstrated to be successful in synthesizing various carbon nanostructures, such as carbon nanotubes and nanosheets. Compared with thermal CVD, PECVD possesses a unique advantage of additional high-density reactive gas atoms and radicals, facilitating low-temperature, rapid, and controllable synthesis. In the current study, we report results in synthesizing of high-quality graphene films on a Ni films at low temperature. Controllable synthesis of quality graphene on Cu foil through inductively-coupled plasma CVD (ICPCVD), in which the surface chemistry is significantly different from that of conventional thermal CVD, was also discussed.

  • PDF

Characteristics of Meta-aramid Fabrics Coated with Slurry of Nanoscale SiC Particles (나노 탄화규소(SiC) 슬러리로 코팅된 메타-아라미드 직물의 특성)

  • Park, Jong Hyeon;Lee, Sun Young;Won, Jong Sung;Lee, Eung Bo;Kim, Eui Hwa;Lee, Seung Goo
    • Textile Coloration and Finishing
    • /
    • v.29 no.3
    • /
    • pp.131-138
    • /
    • 2017
  • Most of high performance fabrics for the car racing protective clothing have been developed to have thermal resistance, flame retardant property, impact resistance and anti-frictional properties to protect the racer from the crucial accident. In this study, the meta-aramid fabric, which has inherent flame retardant, was coated with nanoparticles of SiC to enhance the impact resistance and anti-friction properties. Uniform coating of the nanoparticles onto the fabrics was obtained by using tape casting method. As the experimental parameters, size and content of the SiC nanoparticle were varied with the coating conditions of the fabric surface. The effects of the nanoparticle coating on the properties of meta-aramid fabric were examined with various instrumental analyses such as SEM, tensile strength and abrasion test.

Liquid Crystal Alignment on the SiC Thin Film by the Ion Beam Exposure Method

  • Moon, Hyun-Chan;Kang, Hyung-Ku;Park, Chang-Joon;Hwang, Jeoung-Yeon;Seo, Dae-Shik;Lim, Sung-Hoon;Jang, Jin
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07a
    • /
    • pp.468-470
    • /
    • 2005
  • We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of the SiC (Silicon Carbide) thin film. The SiC thin film exhibits good chemical and thermal stability. The good thermal and chemical stability makes SiC an attractive candidate for electronic applications. A vertical alignment of nematic liquid crystal by ion beam exposure on the SiC thin film surface was achieved. The about $87^{\circ}$ of stable pretilt angle was achieved at the range from $30^{\circ}$ to $45^{\circ}$ of incident angle. The good LC alignment is main-tained by the ion beam alignment method on the SiC thin film surface at high annealing temperatures up to 300.

  • PDF

Polycrystalline Ceramic Fibers by Extrusion

  • Sagesser, Peter;Wegmann, Markus;Gut, Beat;Berroth, Karl;,
    • The Korean Journal of Ceramics
    • /
    • v.4 no.4
    • /
    • pp.382-386
    • /
    • 1998
  • titanate and a silicon carbide/zirconium diboride particulate composite have each been blended with thermoplastic of aqueous binders and extruded. The green extrudates have diameters ranging between 50 and 150 ㎛ and polyethylene-base 150 ${\mu}m$ diameter fibers can be drawn down at elevated temperature to approximately 40 ${\mu}m$ diameter. Hollow fibers with 150${\mu}m$ outer and 90 ${\mu}m$ inner diameter can also be fabricated. Green fibers have been processed into chopped fiber felts for use as gas distributors/current collectors in an experimental solid oxide fuel cell (SOFC) and the first attempts at producing simple textile structures have been successful. The fibers, tubes and felts have been successfully debound and sintered and characterization of the sintered PSZ fibers, for example, has revealed a density in excess of 99% and tensile failure stresses up to 1.0 GPa for 78 ${\mu}m$ diameter fibers.

  • PDF

Mechanical Properties of Cf/SiC Composite Using a Combined Process of Chemical Vapor Infiltration and Precursor Infiltration Pyrolysis

  • Kim, Kyung-Mi;Hahn, Yoonsoo;Lee, Sung-Min;Choi, Kyoon;Lee, Jong-Heun
    • Journal of the Korean Ceramic Society
    • /
    • v.55 no.4
    • /
    • pp.392-399
    • /
    • 2018
  • $C_f/SiC$ composites were prepared via a process combining chemical vapor infiltration (CVI) and precursor infiltration pyrolysis (PIP), wherein silicon carbide matrices were infiltrated into 2.5D carbon preforms. The obtained composites exhibited porosities of 20 vol % and achieved strengths of 244 MPa in air at room temperature and 423 MPa at $1300^{\circ}C$ under an Ar atmosphere. Carbon fiber pull-out was rarely observed in the fractured surfaces, although intermediate layers of pyrolytic carbon of 150 nm thickness were deposited between the fiber and matrix. Fatigue fracture was observed after 1380 cycles under 45 MPa stress at $1000^{\circ}C$. The fractured samples were analyzed by transmission electron microscopy to observe the distributed phases.

Crystal Characteristics of 3C-SiC Thin-films Grown on 2 inch Si(100) wafer (2 inch Si(100)기판위에 성장된 3C-SiC 박막의 결정특성)

  • Chung, Su-Young;Chung, Yun-Sik;Ryu, Ji-Goo;Chung, Gwiy-Sang;Shigehiro, Nishino
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.11a
    • /
    • pp.452-455
    • /
    • 2002
  • Single crystal 3C-SiC(cubic silicon carbide) thin-films were deposited on Si(100) substrate up to a thickness of $4.3{\mu}m$ by APCVD method using HMDS(hexamethyildisilane) at $1350^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like crystal surface. The growth rate of the 3C-SiC films was $4.3{\mu}m/hr$. The 3C-SiC epitaxical films grown on Si(100) were characterized by XRD, AFM, RHEED, XPS and raman scattering, respectively. The 3C-SiC distinct phonons of TO(transverse optical) near $796cm^{-1}$ and LO(longitudinal optical) near $974{\pm}1cm^{-1}$ were recorded by raman scattering measurement. The heteroepitaxially grown films were identified as the single crystal 3C-SiC phase by XRD spectra$(2{\theta}=41.5^{\circ})$.

  • PDF

Growth of Polycrystalline 3C-SiC Thin Films using HMDS Single Precursor (HMDS 단일 전구체를 이용한 다결정 3C-SiC 박막 성장)

  • Chug, Gwiy-Sang;Kim, Kang-San;Han, Ki-Bong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.20 no.2
    • /
    • pp.156-161
    • /
    • 2007
  • This paper describes the characteristics of polycrystalline ${\beta}$ or 3C (cubic)-SiC (silicon carbide) thin films heteroepitaxailly grown on Si wafers with thermal oxide. In this work, the poly 3C-SiC film was deposited by APCVD (atmospheric pressure chemical vapor deposition) method using HMDS (hexamethyildisilane: $Si_{2}(CH_{3}_{6})$ single precursor. The deposition was performed under various conditions to determine the optimized growth conditions. The crystallinity of the 3C-SiC thin film was analyzed by XPS (X-ray photoelectron spectroscopy), XRD (X-ray diffraction) and FT-IR (fourier transform-infrared spectometers), respectively. The surface morphology was also observed by AFM (atomic force microscopy) and voids or dislocations between SiC and $SiO_{2}$ were measured by SEM (scanning electron microscope). Finally, depth profiling was invesigated by GDS (glow discharge spectrometer) for component ratios analysis of Si and C according to the grown 3C-SiC film thickness. From these results, the grown poly 3C-SiC thin film is very good crystalline quality, surface like mirror and low defect. Therfore, the poly 3C-SiC thin film is suitable for extreme environment, Bio and RF MEMS applications in conjunction with Si micromaching.

Analysis of Grinding Characteristics of Ceramic (SiC) Materials (세라믹 소재의 연삭가공 특성 분석)

  • Park, Hwi-Keun;Park, Sang-Hyeon;Park, In-Seung;Yang, Dong-Ho;Cha, Seung-Hwan;Ha, Byeong-Cheol;Lee, Jong-Chan
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.17 no.1
    • /
    • pp.16-22
    • /
    • 2018
  • Silicon carbide (SiC) is used in various semiconductor processes because it has superior thermal, mechanical, and electrical characteristics as well as higher chemical and corrosion resistance than existing materials. Due to these characteristics, various manufacturing technologies have been developed for SiC. A recent development among these technologies is Chemical Vapor Deposition SiC (CVD-SiC). Many studies have been carried out on the processing and manufacturing of CVD-SiC due to its different material characteristics compared to existing materials like RB-SiC or Sintered-SiC. CVD-SiC is physically stable and has excellent chemical and corrosion resistance. However, there is a problem with increasing the thickness, because it is manufactured through a deposition process. Additionally, due to its high strength and hardness, it is difficult to subject to machining.

Characteristics of polycrystalline AlN thin films deposited on 3C-SiC buffer layers for M/NEMS applications (3C-SiC 버퍼층위에 증착된 M/NEMS용 다결정 AlN 박막의 특성)

  • Chung, Gwiy-Sang;Lee, Tae-Won
    • Journal of Sensor Science and Technology
    • /
    • v.16 no.6
    • /
    • pp.462-466
    • /
    • 2007
  • Aluminum nitride (AlN) thin films were deposited on Si substrates by using polycrystalline (poly) 3C-SiC buffer layers, in which the AlN film was grown by pulsed reactive magnetron sputtering. Characteristics of grown AlN films were investigated experimentally by means of FE-SEM, X-ray diffraction, and FT-IR, respectively. The columnar structure of AlN thin films was observed by FE-SEM. X-ray diffraction pattern proved that the grown AlN film on 3C-SiC layers had highly (002) orientation with low value of FWHM (${\Theta}=1.3^{\circ}$) in the rocking curve around (002) reflections. These results were shown that almost free residual stress existed in the grown AlN film on 3C-SiC buffer layers from the infrared absorbance spectrum. Therefore, the presented results showed that AlN thin films grown on 3C-SiC buffer layers can be used for various piezoelectric fields and M/NEMS applications.