• 대한전자공학회논문지
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• 제26권6호
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• pp.63-70
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• 1989

액체금속이온원으로 부터 발생한 AuGe 이온빔을 GaAs기판에 주입시킨 후 이 시료의 표면성분과 구조를 AES(Auger electron spectroscopy), RHEED(reflection high energy electron diffraction), SEM(scanning electron microscopy) and EPMA(electron probe microanalysis)등으로 조사하였으며 AES depth profile 실험결과를 이체충돌에 의한 Monte Carlo simulation과 비교하였다. AuGe 이온이 주입된 시료를 AES, EPMA로 측정한 결과 As의 preferential스피터링이 나타났으며 300$^{circ}$C로 열처리하면 Ga과 outdiffusion되었다. 또한 측정한 Au와 Ge의 depth profile은 이체충돌에 의한 Monte Carlo simulation의 결과와 잘 일치하였다.

• 한국재료학회지
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• 제4권6호
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• pp.638-643
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• 1994

Si(111)표면위에 Au의 증착량과 기판온도에 따른 표면구조의 변화를 RHEED(Reflection High Energy Electron Diffraction)상(pattern)과 RHEED상의 회절반점(spot)강도변화를 이용하여 조사하였다. Si(111) $7\times7$구조를 Au 를 0.1ML-0.4ML증착후에 기판을 $350^{\circ}C$-$750^{\circ}C$로 수초간 가열하면 $7\times7$구조에서 $7\times7$ + $5\times2$의 혼합 구조로 변화하였으며 증착량 0.4ML-1.0ML에서는 RHEED상이 기판온도와 증착량에 따라 $5\times2,\alpha- \sqrt{3} \times \sqrt{3},\beta- \sqrt{3} \times \sqrt{3}$의 구조들이 관찰되었다. $6\times6$구조는 기판온도 $270^{\circ}C$-$370^{\circ}C$에서 증착량 0.8ML에서부터 형성되기 시작하여 1ML에서 완성되었다. AES(Auger Electron Spectroscopy)를 이용한 $\alpha- \sqrt{3} \times \sqrt{3},5 \times 2$구조에서의 Au원자의 이탈과정 조사에서 이탈 에너지는 각각 79kcal/mol, 82kcal/mol로 조사되었다.

• Journal of Magnetics
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• 제7권3호
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• pp.106-114
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• 2002

To reduce the grain size and the media noise in a typical CrMo/CoCrPtB longitudinal media, a sputtering process which includes the exposure of oxygen onto the surface of CrW$_x$ (x=0, 25, 50, 75, 100 at.%) and CrTi$_{15}$ seedlayers with the thickness of 0.5 nm have been utilized. The main results are: (1) the media grain size and the media noise are reduced when using CrW$_x$ (x=0, 25, 50 at.%) seedlayers, and not reduced when using CrTils or CrW$_x$ (x=75, 100 at.%) seedlayers, (2) AES and RHEED results suggest that W seedlayer, which has the highest melting point, forms layer-like film with very small and dense island grain, due to its high free surface energy and low mobility. On the other hand, CrW$_{50}$ and Cr seedlayers, which have lower melting point than W seedlayer, form island film, (3) to effectively reduce the media grain size and improve the media signal to noise ratio, it is essential to utilize a very thin Cr-based seedlayer with high affinity for oxygen and which forms island-like structure, such as CrW$_{50}$ seedlayer.

• 한국진공학회지
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• 제2권2호
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• pp.199-208
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• 1993

Si 기판 표면상태 변화와 관련된 핵생성 자유에너지 증가에 따른 다이아몬드 박막성장 거동을 관찰하였다. 표면 염마조건 변화에 따른 3가지 기판(A-Si, B-Si, C-Si)위에 동일한 성장조건으로 다이아몬드를 성장하였으며, 이때 형상인자와 관련된 자유에너지 관계는 ${\Delta}G_{A-Si}<{\Delta}G_{B-Si}<{\Delta}G_{C-Si}$이다. AES, SEM, XRD, RHEED에 의해 각각의 박막 A, B, C를 조사한 결과, 핵생성 자유에너지가 가장 적은 A 박막은 (100) (110) 면이 지배적인 고품위 다이아몬드 박막이다. 자유에너지가 A에 비해 다소 적은 B 박막은 (111) 면이 지배적인 8면체 다이아몬드 박막이고, 자유에너지가 자장 적은 C 박막은 흑연이 많이 함유된 구상의 다이아몬드이다.

• 한국산업융합학회 논문집
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• 제6권3호
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• pp.201-205
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• 2003

The effects of adsorption and desorption of alkali-metals on Si(111) surface were investigated by using AES and RHEED-system. The adsorption system is a fundamental interest because of its unique electronic properties such as measurement of work function change, adatom-core level shift. It was found that the growth node of K on Si(111) surface was layer by layer growth and the saturation coverage was 2.0ML at room temperature. Superstructure changes on Si(111) surface according to the alkali-metal thickness and substrate temperatures were accurately defined. By applying the isothermal desorption method, the desorption energies of Li/Si(111) and K/Si(111) surfaces was measured. On Li/Si(111) and K/Si(111) surfaces, the desorption energies were 3.07 eV, 2.19 eV respectively.

• 대한전자공학회논문지
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• 제23권3호
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• pp.376-383
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• 1986

In this paper, we show that the growth rate of MBE GaAs epitaxial layer is controlled entirely by the flux density of the Ga beam, impinging on the substrate surface, and is linearly proportional to the Ga effusion cell temperature and the growth time. According to our investigation of the epitaxial layer surfvace through RHEED, AES, SIMS and SEM, if the growth temperature is maintained above 590\ulcorner, the surface crystal structure, flathness and stoichiometry become significantly enhanced, and the epilayer surface has a smooth mirror-like appearance.

• 대한전자공학회논문지
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• 제26권9호
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• pp.1381-1387
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• 1989

For the fabrication of ohmic contact to p-type GaAs, In Liquid Metal Ions were implanted into p-type GaAs (Zn:1.5x10**19/cm**3). After the samples were processed by Infrared rapid thermal annealing (IRTA0 or Furance Annealing (FA), I-V and specific contact contact resistivity were measured. Specific contact resistivity was found to be 1.7x10**-5 \ulcorner-cm\ulcornerin IRTA 750\ulcorner, 10 sec annealed sample. The surface characteristics of the samples were investigated with SEM, RHEED, AES. From these results we can know that implanted In ions were formed mixing layer of InAs at the surface.

• The Korean Journal of Ceramics
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• 제3권3호
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• pp.177-181
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• 1997

Epitaxial films of cubic silicon carbide (3C-SiC, $\beta$-SiC) have been grown on Si(001) and Si(111) substrates by high vacuum chemical vapor deposition using the single precursor 1,3-disilabutane, $H_3SiCH_2SiH_2CH_3$, at temperatures 900~$100^{\circ}C$. The advantage of using the single precursor over the covnentional chemical vapor deposition is evident in that the source chemical is safe to handle, carbonization of the substrates is not necessary, accurate stoichiometry of the silicon carbide films is easily achieved, and the deposition temperature is much lowered. The films were characterized by XPS, XRD, SEM, RHEED, RBS, AES, and TED.

• 대한전자공학회논문지
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• 제22권6호
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• pp.34-40
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• 1985

분자선 에퍼택시 (MBE)방법을 이용하여 (100) GaAs웨이퍼 위에 GaAs에퍼충을 성장시켜 성장된 충에 대한 여러가지 특성을 조사 ·분석하였다. 분자선 에피택시 방법을 이용하여 CaAs에퍼층을 만들 때에는 기판온도와 As와 Ca의 분자선 밀도비 (As/Ga)가 가장 큰 영향을 미친다. 본 실험에서는 좋은 표면상태를 얻기 위해 480℃∼650℃로 유지시키고 As cell의 온도를 230℃, Ga eel함 온도를 917℃로 고정시켜 As와 Ga의 분자선 밀도비를 5∼10 이상으로 유지시켰다. 제작된 GaAs에피층의 표면상태를 SIMS (Seconde,y ion Mass ipectoscopy), AES(Auger Electron Spectroscopy) , SEM (Scanning Elect.on Mic,oscopy) , RHEED (Reflection High Energy Electron Diffraction) 등으로 조사한 결과 기판온도가 540℃일 때 가장 좋은 표면상태를 얻을 수 있었다. 또한 RH-EED관찰 결과 As 안정화된 표면을 관측할 수 있었으며 SIMS로 depth-Profile을 해 본 곁과, Ca 보다 As가 불안정함을 알았다. 또한 반선 회절 검사결과에서 기판온도가 520℃일때와 540℃일때 (400), (200)면에 단결정이 형성되었음을 알 수 있었다.

• 대한전자공학회논문지
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• 제23권2호
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• pp.243-248
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• 1986

The impurities in As and Ga sources and the contamination of the GaAs substrate prior to growing of MBE GaAs epitaxial layer have been investigated using RHEED, AES and RGA methods. The as source was contaminated by H2O, CO, CO2 and AsO, and the Ga source was contaminated by H2, H2O, CO and CO2. These contaminants could easily be removed by prebaking the source. On the other hand, GaAs substrate was contaminated principally carbon and oxygen. The oxygen could easily be removed by heating the substrate above 480\ulcorner, and the carbon could also be reduced by sputtering the substrate with 1ke V Ar+. The chemically etched substrate surface prior to growing the layer was rough, but it was made to be smooth and clean by heating it above 530 \ulcorner.