• 한국결정성장학회지
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• 제13권6호
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• pp.290-296
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• 2003

본 연구에서는 열화학기상증착법을 사용하여 6H-SiC 기판 위에 silane($SiH_4$)과 prophane($C_3H_8$)을 사용하여 3C-SiC 이종박막을 성장시키고 이의 성장 특성을 조사하였다. C/Si 유량 비율이 4.0, 운반기체의 유량은 5 slm이고 성장온도가 $1200^{\circ}C$인 경우의 박막성장율은 약 1.8 $\mu$m/h이었다. 성장박막의 Nomarski 표면형상, X-선 회절분광, Raman 산란 특성 및 광발광(PL) 특성 등을 측정하고 성장조건에 따른 결정성을 비교하였다. 이러한 평가를 통하여 성장온도 $1150^{\circ}C$ 이상에서 양질의 결정성 3C-SiC 이종박막이 성장점을 확인하였다.

• 한국결정성장학회지
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• 제10권1호
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• pp.5-12
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• 2000

Silicon carbide(SiC)는 뛰어난 전기적, 열적, 물리적 특성 때문에 내환경 전자소자용 반도체 재료로 널리 연구되고 있다. 본 연구에서는 화학기상증착법으로 단결정 6H-SiC 동종박막을 성장시키고 이의 성장 특성을 조사하였다. 특히, 몰리브덴 (Mo)-plate를 이용하여 SiC를 코팅하지 않은 graphite susceptor를 사용한 6H-SiC 동종박막 성장조건을 성공적으로 얻었다. 대기압 상태의 RF-유도가열식 챔버에서 CVD성장을 수행하였고, <1120> 방향으로 $3.5^{\circ}$off-axis된 기판을 사용하였다. 성장 박막의 결정성을 평가하기 위하여 Nomarski 관찰, 투과율 측정 , 라만 분광, XRD, 광발광(PL) 분광, 투과전자현미경(TEM) 측 정 등의 방법을 이용하였다. 이상과 같은 실험을 통하여, 본 연구에서는 성장온도 $1500^{\circ}C$, C/Si flow ratio ($C_3H_8$ 0.2 sccm, $SiH_4$ 0.3 sccm)인 성장조건에서 결정성이 가장 좋은 6H-SiC 동종박막을 얻을 수 있었다.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1997년도 Proceedings of the 12th KACG Technical Meeting and the 4th Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.269-274
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• 1997

Silicon carbide(SiC) epilayers were grown by a thermal CVD(chemical vapor deposition) process, and their crystalline properties were investigated. Especially, the growth conditions of 6H-Sic homoepitaxial layers were obtained using a SiC-uncoated graphite susceptor that utilized Mo-plates. In order to investigate the crystallinity of grown layers, Nomarski photograph, transmittance, XRD, Raman, PL and TEM measurements were used. The best quality of 6H-SiC epilayers was obtained in conditions of growth temperature 1500$^{\circ}C$ and C/Si ratio 2.0.

• ALGAE
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• 제19권3호
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• pp.201-205
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• 2004

An ectoparasitic din flagellate infesting plank tonic chaetognath, Sagitta crassa Tokioka was found, for the first time, from Korean coasts. In order to identify the species, we investigated detailed morphology of the din flagellate using Nomarski interference optics as well as epifluorescent microscopes. The parasitic din flagellate consists of an oval to rod-shaped cell with a peduncle, by which the organism attaches to the host. The cell is covered with polygonal thecal plates. The nucleus displays two different shapes according to cell cycle stages: in young trophont the nucleus is elongated and shows typical din flagellate nucleus (dinokaryon), while in matured trophont, the nucleus is dome-shaped and non-dinokaryotic. The peduncle is variable in length and is ornamented with the longitudinal striations. All these characteristics point to identity that the ectoparasitic din flagellate infecting Sagitta crassa in Korean coasts is Oodinium inlandicum Horiguchi et Ohtsuka, originally described from the Seto Inland Sea of Japan. Relationship between prevalence and host sizes differed from those in Japan.

• 한국광학회:학술대회논문집
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• 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.49-53
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• 1990

Laser plasma was generated by a 1 GW iodine photodissociation laser(λ=1.315${\mu}{\textrm}{m}$, E-12.7J) whose output beam was focused on a molybdenum target surface. The experiment was conducted in the vacuum chamber under 10-5Torr and several tens of laser shooting were necessary for sufficient exposure to the PBS resist. A speciman was put directly on the resist and located at a distance of 3cm from the X-ray source. The replicas of a mesh, spider's tread, a red blood cell were obtained by PBS resist and were analyzed by Nomarski and SEM. Two main effects of limitation in resolution, source size and Fresnel diffraction, are mentioned and compared with the experimental result. In this experiment, a resolution better than 1000A could be obtained.

• 한국정밀공학회지
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• 제19권6호
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• pp.145-154
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• 2002

CMP (Chemical mechanical polishing) process was used to control the fine grinding process induced mechanical damage of Cz Silicon wafer. Characterization of mechanical damage was carried out using Nomarski microscope, magic mirror and also using angle lapping and lifetime scanner evaluation after heat treatment. Magic mirror and lifetime scanner were very useful for the residual damage pattern characterization and CMP process was effective on the reduction of fine grinding induced mechanical damage.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권5호
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• pp.695-701
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• 2016

Be-doped GaSb layers were grown on highly mismatched semi-insulating GaAs substrate (001) with $2^{\circ}$ offcut towards <110> at low growth temperature, by molecular beam epitaxy (MBE). The influence of Be doping on the crystallographic quality, surface morphology, and electrical properties, was assessed by X-ray diffraction, Nomarski microscopy, and Hall effect measurements, respectively. Be impurities are well behaved acceptors with hole concentrations as high as $9{\times}10^{17}cm^{-3}$. In addition, the reduction of GaSb lattice parameter with Be doping was studied.

• 대한전자공학회논문지
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• 제27권4호
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• pp.527-533
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• 1990

Zone-melting recrystallization (ZMR) system using two graphite heaters(a stationary sheet and a narrow movable bar) was constructed and implemented in recrystallization op Si films on insulating layers. The recystallized Si films were examined by Nomarski contrast optical microscopy after Dash etching, transmission electron diffraction pattern, and x-ray diffraction. With optimum conditions of process parameters(input powers of the bottom and upper heater, scanning speed of the upper heater, and the gap between sample and upper heater), the recrystallized Si layer has a (100) texture, but contains many subboundaries. The subgrains are misoriented by < 0.5\ulcorner and the average spacing between subboundaries is about 25\ulcorner.

• 전자공학회논문지A
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• 제28A권5호
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• pp.380-386
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• 1991

Hydrogen plasma-assisted epitaxial(PAE) growth of GaAs/Si and GaAs/Ge/Si with Ge buffer layer has been investigated. By means of photoluminescence, Nomarski microscopu, and $\alpha$-step, it could be known that GaAs on Si with Ge buffer layer has better crystalline quality than GaAs on Si without Ge buffer layer. The stoichiometry of GaAs layer on Si was confirmed by the depth profile of Auger electron spectroscope (AES). Also the native oxide(SiO$_2$) layer on Si substrate was plama-etched and the removal of the oxide layer was confirmed by AES. Photoluminescence peak wavelength of GaAs/Ge/Si with Ge buffer of 1\ulcorner thickness and GaAs growth rate of 160$\AA$/min was 8700$\AA$and FWHM was 12$\AA$.

• 한국재료학회지
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• 제6권6호
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• pp.626-631
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• 1996

Reactive dc magnetron sputtering 법을 이용하여 증착한 molybdenum mitride 박막의 Cu 확산 방지막 특성을 조사하였다. Cu 확산 방지막으로서 molybdenum nitride 박막의 열적안정성을 관찰하기 위하여 molybdenum nitride 박막 위에 Cu를 evaporation 법으로 증착하고 진공 열처리하였다. Cu/r-Mo2N/si 구조는 $600^{\circ}C$, 30분간 열처리 시까지 안정하였다. 확산 방지막의 파괴는 $650^{\circ}C$, 30분간 열처리 시부터 격자 확산(lattice diffusion)이나 입계(grain boundary)과 결함(defect)을 통한 확산에 의해 나타나기 시작하였고, 이 때 molybdenum silicide과 copper silicide의 형성에 기인된 것으로 생각되었다. 열처리 이후 Cu/r-Mo2N/Si 사이의 상호반응이 증가하였다. 이는 Rutherford backscattering spectrometry, Auger electron spectroscopy 그리고 Nomarski microscopy 등의 분석을 통해 조사되었다.