• Korean Journal of Materials Research
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• v.10 no.4
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• pp.276-281
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• 2000

Silicon carbide(SiC) films were grown on modified Si(111) surface with a SiNx in the NH$_3$surrounding. Thickness of SiC films was decreased with increasing of the nitridation time. Also, voids having crystal defects were removed at interface of SiC/Si according to growth parameters. SiC films were grown on SiNx/Si substrate of 100, 300 and 500nm thickness. SiC films were deposited along [111] direction and columnar grains of SiC crystal. The void-free film was observed in the interface of SiC/SiNx. This result suggests that fabrication of SiC devices are applied to SiNx replacing silicon oxide in SOI structure.

• Journal of the Korean institute of surface engineering
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• v.51 no.2
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• pp.110-115
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• 2018

The Na low temperature gettering in $SiO_2/PSG/SiO_2/Al-1%Si$ and $SiO_2/TEOS/SiO_2/Al-1%Si$ multilevel thin films was investigated using dynamic SIMS(secondary ion mass spectrometry) analysis. DC magnetron sputter, APCVD and PECVD techniques were utilized for the deposition of Al-1%Si thin films, $SiO_2/PSG/SiO_2$ and $SiO_2/TEOS/SiO_2$ passivations, respectively. Heat treatment was carried out at $300^{\circ}C$ for 5 h in air. SIMS depth profiling was used to determine the distribution of Na, Al, Si and other elements throughout the $SiO_2/PSG/SiO_2/Al-1%Si$ and $SiO_2/TEOS/SiO_2/Al-1%Si$ multilevel thin films. XPS was used to analyze chemical states of Si and O elements in $SiO_2$ passivation layers. Na peaks were observed throughout the $PSG/SiO_2$ and $TEOS/SiO_2$ passivation layers on the Al-1%Si thin films and especially at the interfaces. Na low temperature gettering in $SiO_2/PSG/SiO_2/Al-1%Si$ and $SiO_2/TEOS/SiO_2/Al-1%Si$ multilevel thin films is considered to be caused by a segregation type of gettering.

• Korean Journal of Materials Research
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• v.25 no.5
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• pp.258-263
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• 2015

To fabricate porous SiC-Si composites for heating element applications, both SiC powders and Si powders were mixed and sintered together. The properties of the sintered SiC-Si body were investigated as a function of SiC particle size and/or Si particle contents from 10 wt% to 40 wt%, respectively. Porous SiC-Si composites were fabricated by Si bonded reaction at a sintering temperature of $1650^{\circ}C$ for 80 min. The microstructure and phase analysis of SiC-Si composites that depend on Si particle contents were characterized using scanning electron microscope and X-ray diffraction. The electrical resistivity of SiC-Si composites was also evaluated using a 4-point probe resistivity method. The electrical resistivity of the sintered SiC-Si body sharply decreased as the amount of Si addition increased. We found that the electrical resistivity of porous SiC-Si composites is closely related to the amount of Si added and at least 20 wt% Si are needed in order to apply the SiCSi composites to the heating element.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.27-31
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• 2001

Hi-Nicalon SiC fiber reinforced SiC composites (SiC/SiC) have been fabricated by the reaction sintering process. Braided Hi-Nicalon SiC fiber with double interphases of BN and SiC was used in this composite system. The microstructures and the mechanical properties of reaction sintered SiC/SiC composites were investigated through means of electron microscopies (SEM, TEM, EDS) and bending tests. The matrix morphology of reaction sintered SiC/SiC composites was composed of the SiC phases that the composition of the silicon and the carbon is different. The TEM analysis showed that the residual silicon and the unreacted carbon were finely distributed in the matrix region of reaction sintered SiC/SiC composites. Reaction sintered SiC/SiC composites also represented proper flexural strength and fracture energy, accompanying the noncatastrophic failure behavior.

• Korean Journal of Materials Research
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• v.8 no.2
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• pp.165-172
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• 1998

Epitaxial ultrathin films of $CoSi_2$ and double heteroepitaxial structure of Si/$CoSi_2$/Si(lll) were prepared on Si(111)-$7\times{7}$ substrate by in situ solid-phase epitaxy in a ultrahigh vacuum(LHV). The phase, chemical composition, crystallinity, and the microsructure of the Si/$CoSi_2$/Si(lll) interface were investigated by 2-MeV $^4He^{++}$ ion backscattering spectrometry, X-ray diffraction, and high-resolution transmission electron microscopy. The growth mode of the Co film was the Stransky-Krastanov type with texture when the substrate temperature was room temperature. A-type $CoSi_2$ ultrathin film was grown by deposition of about 50A Co on Si(ll1)-$7\times{7}$ substrate followed by in situ annealing at $700^{\circ}C$ for 10 min. The matching face relationships were $CoSi_2$[110]//Si[110] and $CoSi_2$(002)//Si(002) with no misorientation angle. The A-type $CoSi_2$/Si(lll) interface was abrupt and coherent. The best epi-Si/epi-$CoSi_2$2(A-type)/Si(lll) structure was obtained by deposition of Si film on the CoSii at $500^{\circ}C$ followed by in situ annealing at $700^{\circ}C$ for 10 min in UHV.

• Journal of the Korean Ceramic Society
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• v.36 no.6
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• pp.655-661
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• 1999

${\beta}$-SiC formation mechanism in Si melt-C-SiC system with varying in size of carbon source was investigated. A continuous reaction sintering process using Si melt infiltration method was adopted to control the reaction sintering time effectively. It was found that ${\beta}$-SiC formation mechanism in Si melt-C-SiC system was directly affected by the size of carbon source. In the Si melt-C-SiC system with large carbon source ${\beta}$-SiC formation mechanism could be divided into two stages depending on the reaction sintering time: in early stage of reaction sintering carbon dissolution in Si melt and precipitation of ${\beta}$-SiC was occurred preferentially and then SIC nucleation and growth was controlled by diffusion of carbon throughy the ${\beta}$-SiC layer formed on graphite particle. Furthmore a dissolution rate of graphite particles in Si melt could be accelerated by the infiltration of Si melt through basal plane of graphite crystalline.

• Journal of the Korean Ceramic Society
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• v.51 no.5
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• pp.459-465
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• 2014

In this study, Si-SiC composites were fabricated using a Si melt infiltration method using ${\beta}$-SiC/C composite powders synthesized by the carbothermal reduction of $SiO_2-C$ precursors made from a TEOS and a phenol resin. The purity of the synthesized SiC-C composite powders was higher than 99.9993 wt% and the average particle size varied from 4 to $6{\mu}m$ with increasing carbon contents of the $SiO_2-C$ precursors. It was found that the Si-SiC composites fabricated in this study consist of ${\beta}$-SiC and residual Si, without any trace of ${\alpha}$-SiC. The 3-point bending strengths of the fabricated Si-SiC composites were measured and found to be higher than 550 MPa, although the density of the fabricated Si-SiC composite was less than $2.9g/cm^3$. The bending strengths and the densities of the fabricated Si-SiC composites were found to decrease with increasing C/Si mole ratios in the SiC-C composite powders. The specific resistivities of the Si-SiC composites fabricated using the SiC-C composite powders were less than $0.018{\Omega}cm$. With increasing C content in the SiC-C composite powders used for the fabrication of Si-SiC composites, the specific resistivity of the Si-SiC composites was found to slightly increase from 0.0157 to $0.018{\Omega}cm$.

• Journal of Pharmacopuncture
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• v.7 no.2
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• pp.57-64
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• 2004

This study was carried to identify the component of Small Intestine Meridian Muscle in human, dividing the regional muscle group into outer, middle, and inner layer. the inner part of body surface were opened widely to demonstrate muscles, nerve, blood vessels and the others, displaying the inner structure of Small Intestine Meridian Muscle. We obtained the results as follows; 1. Small Intestine Meridian Muscle is composed of the muscle, nerve and blood vessels. 2. In human anatomy, it is present the difference between a term of nerve or blood vessels which control the muscle of Meridian Muscle and those which pass near by Meridian Muscle. 3. The inner composition of meridian muscle in human arm is as follows ; 1) Muscle ; Abd. digiti minimi muscle(SI-2, 3, 4), pisometacarpal lig.(SI-4), ext. retinaculum. ext. carpi ulnaris m. tendon.(SI-5, 6), ulnar collateral lig.(SI-5), ext. digiti minimi m. tendon(SI-6), ext. carpi ulnaris(SI-7), triceps brachii(SI-9), teres major(SI-9), deltoid(SI-10), infraspinatus(SI-10, 11), trapezius(Sl-12, 13, 14, 15), supraspinatus(SI-12, 13), lesser rhomboid(SI-14), erector spinae(SI-14, 15), levator scapular(SI-15), sternocleidomastoid(SI-16, 17), splenius capitis(SI-16), semispinalis capitis(SI-16), digasuicus(SI-17), zygomaticus major(Il-18), masseter(SI-18), auriculoris anterior(SI-19) 2) Nerve ; Dorsal branch of ulnar nerve(SI-1, 2, 3, 4, 5, 6), br. of mod. antebrachial cutaneous n.(SI-6, 7), br. of post. antebrachial cutaneous n.(SI-6,7), br. of radial n.(SI-7), ulnar n.(SI-8), br. of axillary n.(SI-9), radial n.(SI-9), subscapular n. br.(SI-9), cutaneous n. br. from C7, 8(SI-10, 14), suprascapular n.(SI-10, 11, 12, 13), intercostal n. br. from T2(SI-11), lat. supraclavicular n. br.(SI-12), intercostal n. br. from C8, T1(SI-12), accessory n. br.(SI-12, 13, 14, 15, 16, 17), intercostal n. br. from T1,2(SI-13), dorsal scapular n.(SI-14, 15), cutaneous n. br. from C6, C7(SI-15), transverse cervical n.(SI-16), lesser occipital n. & great auricular n. from cervical plexus(SI-16), cervical n. from C2,3(SI-16), fascial n. br.(SI-17), great auricular n. br.(SI-17), cervical n. br. from C2(SI-17), vagus n.(SI-17),hypoglossal n.(SI-17), glossopharyngeal n.(SI-17), sympathetic trunk(SI-17), zygomatic br. of fascial n.(SI-18), maxillary n. br.(SI-18), auriculotemporal n.(SI-19), temporal br. of fascial n.(SI-19) 3) Blood vessels ; Dorsal digital vein.(SI-1), dorsal br. of proper palmar digital artery(SI-1), br. of dorsal metacarpal a. & v.(SI-2, 3, 4), dorsal carpal br. of ulnar a.(SI-4, 5), post. interosseous a. br.(SI-6,7), post. ulnar recurrent a.(SI-8), circuirflex scapular a.(SI-9, 11) , post. circumflex humeral a. br.(SI-10), suprascapular a.(SI-10, 11, 12, 13), first intercostal a. br.(SI-12, 14), transverse cervical a. br.(SI-12,13,14,15), second intercostal a. br.(SI-13), dorsal scapular a. br.(SI-13, 14, 15), ext. jugular v.(SI-16, 17), occipital a. br.(SI-16), Ext. jugular v. br.(SI-17), post. auricular a.(SI-17), int. jugular v.(SI-17), int. carotid a.(SI-17), transverse fascial a. & v.(SI-18),maxillary a. br.(SI-18), superficial temporal a. & v.(SI-19).

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.1-7
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• 2004

In order to enhance the electron mobility in SOI n-MOSFET, we fabricated fully depletion(FD) n-MOSFET on the strained Si/relaxed SiGa/SiO$_2$/Si structure(strained Si/SGOI) formed by inserting SiGe layer between a buried oxide(BOX) layer and a top silicon layer. The summated thickness of the strained Si and relaxed SiGe was fixed by 12.8 nm and then the dependency of electron mobility on strained Si thickness was investigated. The electron mobility in the FD n-MOSFET fabricated on the strained Si/SGOI enhanced about 30-80% compared to the FD n-MOSFET fabricated on conventional SOI. However, the electron mobility decreased with the strained Si thickness although the inter-valley phonon scattering was reduced via the enhancement of the Ge mole fraction. This result is attributed to the increment of intra-valley phonon scattering in the n-channel 2-fold valley via the further electron confinement as the strained Si thickness was reduced.

• Journal of the Korean Vacuum Society
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• v.3 no.4
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• pp.405-413
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• 1994

초고진공에서 기판 Si(111)-7$\times$7 위에 Ti:Si 또는 1:2의 조성비로 Ti와 Si을 동시증착한 후 in situ 열처리하여 TiSi2 박막을 에피택셜 성장시켰다 XRD와 XPS 분석결과 동시증착된 혼합 층에서 C49-TiSi2 박막의 성장은 핵형성에 의함을 확인하였으며 양질의 C49-TiSi2 박막은 Ti를 증착한후 Ti와 Si를 동시 증착한 (Ti+2Si)/(Ti)/Si(111)-7$\times$7구조의 시료를 초고진공에서 50$0^{\circ}C$에서 열처리하여 얻을수 있었다. 형성된 C49-TiSi2/Si(111)의 계면은 깨끗하였고 HRTEM 분석 결과 C49-TiSi2\ulcornerSi(111)의 계면은 약 10。 의 편의를 가지면서 TiSi2[211]∥Si[110] TiSi2(031)/Si(111) 의 정합성을 가졌으며 시료의 전 영 역에 에피택셜 성장되었다.