• The Korean Journal of Ceramics
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• 제2권4호
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• pp.197-202
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• 1996

The highly oriented diamond particles were deposited on the mirror-polished (100) silicon substrates in the bell-jar type microwave plasma deposition system using a three-step process consisting if carburization, bias-enhanced nucleation and growth. By adjusting the geometry of the substrate and substrate holder, very dense disc-shaped plasma was formed over the substrate when the bias voltage was below -200V. Almsot perfectly oriented diamond films were obtained only in this dense disc-shaped plasma. From the results of the optical emission spectra of the dense disc-shaped plasma, it was found that the concentrations of atomic hydrogen and hydrocarbon radical were increased with negative bias voltage. It was also found that the highly oriented diamonds were deposited in the region, where the intensity ratios of carbonaceous species to atomic hydrogen are saturated.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 춘계학술발표강연 및 논문개요집
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• pp.113-113
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• 2003

ZnO 박막은 p형 도핑방법이 점차 알려 지면서 최근 차세대 발광소자 재료로서 주목을 받고 있으며, 우수한 전자 이동도, 우수한 홀 이동도, 발광 스펙트럼(PL) 피크의 날카로움, 높은 free exciton binding energy, 방사선 노출에 대한 큰 내구성, 습식 식각이 가능, 동종 기판 사용이 가능함으로써 박막의 품질을 개선할 수 있고 제조공정을 간소화할 수 있는 등의 장점을 지니고 있어 이에 관련된 많은 연구들이 진행되고 있다. 특히 ZnO 박막을 차세대 발광소자로 응용하기 위해서는 고품질의 에피탁시 박막을 성장시켜야 하며 이를 위하여 MBE, MOCVD, PLD법 등 다양한 에피탁시 박막증착이 시도되고 있다. 또한 보다 양질의 ZnO 박막을 성장시키기 위해 적절한 단결정 기판 및 버퍼층의 탐색과 각 기판에 따른 ZnO 박막의 물성평가 작업도 진행되고 있다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.175-175
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• 2003

ZnO 박막은 그 동안 어려운 문제로 여겨진 p형 도핑방법이 점차 알려 지면서 발광소자 적용 가능성이 주목받고 있다. ZnO는 발광 스펙트럼(PL) 피크의 날카로움, 높은 exciton 결합에너지, 습식식각의 가능, 벽개면 형성의 용이함 및 동종 기판 적용 가능 등의 본질적인 장점을 지니고 있어 재현성있는 p형 도핑방법 기술이 확립된다면 이를 이용한 발광소자 적용 시 기존의 질화물계에 비하여 우수한 소자 제조 가능성이 있다. 이에 따라 국내외에서 ZnO 박막제조에 관련된 많은 연구들이 진행되고 있다. 특히 ZnO 박막을 발광소자로 적용하기 위해서는 고품질의 에피탁시 박막을 성장시켜야 하며 이를 위하여 MBE, MOCVD, PLD법 등 다양한 에피탁시 박막증착이 시도되고 있다. 또한 보다 양질의 ZnO 박막을 성장시키기 위해 적절한 단결정 기판 및 버퍼층의 탐색과 각 기판에 따른 ZnO 박막의 물성평가 작업도 국내외의 여러 연구그룹에서 진행되고 있다.

• 한국세라믹학회지
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• 제55권2호
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• pp.108-115
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• 2018

The increasing demands for three-dimensional (3D) electronic and optoelectronic devices have triggered interest in epitaxial growth of 3D semiconductor materials. However, most of the epitaxially-grown nano- and micro-structures available so far are limited to certain forms of crystal arrays, and the level of control is still very low. In this review, we describe our latest progress in 3D epitaxy of oxide and nitride semiconductor crystals. This paper covers issues ranging from (i) low-temperature solution-phase synthesis of a well-regulated array of ZnO single crystals to (ii) systematic control of the axial and lateral growth rate correlated to the diameter and interspacing of nanocrystals, as well as the concentration of additional ion additives. In addition, the critical aspects in the heteroepitaxial growth of GaN and InGaN multilayers on these ZnO nanocrystal templates are discussed to address its application to a 3D light emitting diode array.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.6-6
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• 2010

This paper describes that single crystal cubic silicon (3C-SiC) films have been deposited on carbonized Si(100) substrate using hexamethyldisilane(HMDS, $Si_2(CH_3)_6$) as a safe organosilane single-source precursor and a nonflammable mixture of Ar and $H_2$ gas as the carrier gas by APCVD at $1280^{\circ}C$. The 3C-SiC film had a very good crystal quality without defects due to viods, a very low residual stress.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.298-303
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• 2001

The critical thickness of an epitaxial film on a substrate in electronic or optoelectronic devices is studied on the basis of equilibrium dislocation analysis. Two geometric models, a single dislocation and an array of dislocations in heteroepitaxial system, are considered respectively to calculate the misfit dislocation formation energy. The isotropic linearly elastic stress fields for the models are obtained by means of complex potential method combined with alternating technique, and are used for calculating the formation energies. As a result, the effect of elastic mismatch between film and substrate on critical thickness is presented and $Si_xGe_{1-x}/Si$ epitaxial structure is analyzed to predict the critical thickness with varying germanium concentration.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.302.1-302.1
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• 2014

We report the growth of high quality zinc oxide (ZnO) thin films on amorphous glass substrates and their structural and optical characteristics. For the growth of ZnO films, mechanically exfoliated ultrathin graphite or graphene layers were used as an intermediate layer because ZnO does not have any heteroepitaxial relationship with the amorphous substrates, which significantly improved the crystallinity of the ZnO films. Structural and optical characteristics of the films were investigated using scanning and transmission electron microscopy, x-ray diffraction, and variable temperature photoluminescence spectroscopy. High crystallinity and excellent optical characteristics such as stimulated emission were exhibited from the high quality ZnO films grown on glass substrates.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.95-96
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• 2005

The general method and mechanism for the polarity control of heteroepitaxial wurtzite films, such as ZnO and GaN, by interface engineering via plasma-assisted molecular beam epitaxy are addressed. We proposed the principle and method controlling the crystal polarity of ZnO on GaN and GaN on ZnO. The crystal polarity of the lower film was maintained by forming a heterointerfce without any interface layer between the upper and the lower layers. However the crystal polarity could be changed by forming the heterointerface with the interface layer having an inversion center. The principle and method suggested here give us a promising tool to fabricate polarity inverted heterostructures, which applicable to invent novel heterostructures and devices.

• The Korean Journal of Ceramics
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• 제3권3호
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• pp.163-168
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• 1997

Most of heteroepitaxial $\beta$-SiC thin films have been successfully grown on Si(100) adapting a carburizing process, by which a few atomic layers of substrate surface is chemically converted to very thin SiC layer using hydrocarbon gas sources. Using an organo-silicon precursor, bis-trimethylsilymethane (BTMSM, [$C_7H_{20}Si_2$]), heteropitaxial $\beta$-SiC thin films were successfully grown directy on Si substrate without a carburized buffer layer. The defect density of the $\beta$-SiC thin films deposited without a carburized layer was as low as that of $\beta$-SiC films deposited on carburized buffer layer. In addition, void density was also reduced by the formation of self-buffer layer using BTMSM instead of carburized buffer layer. It seems to be mainly due to the characteristic bonding structure of BTMSM, in which Si-C was bonded alternately and tetrahedrally (SiC$_4$).

• 한국표면공학회지
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• 제29권5호
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• pp.467-473
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• 1996

Heteroepitaxial growth of cubic silicon carbide films on Si(001) and Si(111) substrates at temperatures 900-$1000^{\circ}C$ has been achieved by high vacuum chemical vapor deposition using the single precursor 1, 3-disilabutane without carrying out the carbonization process of the substrate surfaces. The deposition temperature range is much lowered compared with conventiontional chemical vapor deposition where separate sources for silicon and carbon are employed. The deposition procedure is quite simple and safe. The qualities of the films were found to be very good judging from the results obtained by various characterization techniques including reflection high energy electron diffraction, X-ray diffraction, X-ray pole figure analysis, Rutherford backscattering spectrometry, Auger depth profiling, and transmission electron diffraction.