• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.102.1-102.1
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• 2010

고효율 멀티정션박막태양전지의 바텀셀 적용을 목적으로, 반응성CVD(Reactive thermal CVD)기술을 이용, $Si_2H_6+GeF_4$를 원료가스로, 이들이 가진 산화환원반응을 이용하여 400도 이하의 저온에서 Ge 및 Si 기판에 Ge을 에피성장 시켰다. Ge 기판위의 호모에피막의 경우, $2.5{\AA}/sec$의 성장속도와 99%의 Ge조성을 보였고, RHEED 및 HR-XRD를 통한 결정성 평가 결과, 고품질의 Ge 에피막의 성장이 확인되었다. 동일한 성장조건을 Si기판에 헤테로에피성장 시켰을 경우, 4% 격자불일치에 의해 막품질이 저하되는 것을 확인하였다. 이를 개선하기 위하여 저온에서 제작한 버퍼층에 대한 논의를 하고자 한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05d
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• pp.45-48
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• 2003

BiSrCaCuO thin films were fabricated by atomic layer-by-layer deposition using an ion beam sputtering method. 10 wt% and 90 wt% ozone mixed with oxygen were used with ultraviolet light irradiation to assist oxidation. At early stages of the atomic layer by layer deposition, two dimensional epitaxial growth which covers the substrate surface would be suppressed by the stress and strain caused by the lattice misfit, then three dimensional growth takes place. Since Cu element is the most difficult to oxidize, only Sr and Bi react with each other predominantly, and forms a buffer layer on the substrate in an amorphous-like structure, which is changed to $SrBi_2O_4$ by in-situ anneal.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.37-37
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• 2003

Ferroelectric random acess memories (FeRAMs) 재료로 주목받고 있는 강유전 물질은 이미 여러 해 전부터 많은 물질들에 대해 연구가 진행되어 왔다. 그 중 낮은 공정 온도를 가지며 큰 remanent polarization 값을 갖는 lead zirconium titanate (PZT) 박막에 대해 많은 연구가 진행되고 있다. 하지만 Pt 기판위에 증착된 PZT 박막은 높은 피로 현상을 보이는 문제가 있다. 최근 Pulsed laser deposition이나 metal-organic vapor phase epitaxy (MOVPE) 등의 방법에 의해 epitaxial substituted-$Bi_4Ti_3O_{12}$ (La, Nd) 박막에 대해 보고가 되고 있다. 본 연구에서는 높은 remanent polarization 값을 갖는 $(Bi,Ce)_4Ti_3O_{12}$ (BCT) 박막을 pulsed laser deposition 방법을 사용하여 증착하였다. 또한 Bismuth의 양을 변화시켜 Bismuth의 양에 따른 remanent polarization의 변화를 확인하여 보았다. 사용된 기판은 Pt/$TiO_2$/$SiO_2$/Si 기판을 사용하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.166-166
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• 2003

Si (100) 기판위에서 에피텍셜하게 자란 CoSi$_2$층은 우수한 열적안정성, 낮은 junction leakage, ultra-Shallow junction형성 등의 장점으로 인하여 많은 주목을 받아왔다. 그래서 에피텍셜 CoSi$_2$층을 형성하기 위한 많은 방법들이 보고되어 왔다. 그 방법으로는 Ti나 TiN층을 이용한 interlayer mediated epitaxy, Co의 제한적 공급을 통한 molecular beam epitaxy와 molecular beam allotaxy, 그리고 금속유기소스를 이용한 반응성화학기상증착법등이 있다. 하지만 이 방법들은 복잡한 증착공정과 열처리 후 잔류층 제거의 어려움등을 가지고 있다. 본 연구는 일반적으로 사용되는 Ti나 oxide의 중간층없이 에피층을 형성시키는 새로운 방법으로 CO-O-N 박막으로부터 열처리에 의해 확산된 Co로부터 CoSi$_2$에피층을 형성시켰다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.97-100
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• 2000

Si$_2$Sr$_2$CuO$\sub$x/(Bi(2201)) thin films are fabricated by atomic layer by layer deposition using ion beam sputtering(IBS) method. During the deposition, 10 %-ozone/oxygen mixture gas of typical 5.0 ${\times}$ 10$\^$-5/ Torr is applied with ultraviolet light irradiation for oxidation. XRD and RHEED investigations reveal out that a buffer layer with some different compositions is formed at the early deposition stage of less than 10 units cell and then c-axis oriented Bi(2201) is grown.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.10
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• pp.855-860
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• 2001

Bi$_2$Sr$_2$CuO$_{x}$(Bi-2201) thin film were fabricated by atomic layer-by -layer deposition using an ion beam sputtering method. 10 wt% and 90 wt% ozone mixed oxygen were used with ultraviolet light irradiation to assist oxidation. XRD and RHEED investigations revealed that a buffer layer is formed at the early stage of deposition (less than 10 unit cell), and then c-axis oriented Bi-2201 grows on top of it.t.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.71-74
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• 1998

$Er^{3+}$ doped $NdF_{3}$ single crystalline thin films with smooth, microcrack-free, and high-crystalline quality were grown on $CaF_{2}(111)$ substrate at $500^{\circ}C$by molecular beem epitaxy(MBE). The relation-ship between subcell and supercell showing the reconstructed $3^{1/2} \times 3^{1/2}$ structure was studied by reflection high-energy electron diffraction(RHEED) investigation. The film surface and the growth mode were examined in studied by RHEED patterns and atomic force microscope(AFM) images ex situ. The crystallinity of film and the lattice mismatch between $NdF_{3}Er}^{3+}(0002)$ film and $CaF_{2}(111)$ substrate depending in the $Er^{3+}$ concentration were investigated by X-ray rocking curve analysis.

• Journal of Magnetics
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• v.17 no.4
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• pp.261-264
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• 2012

Interfacial properties of 5 nm MgO(001)/7 nm Fe(001)/1.8 nm MgO(001)/t nm Cu-phthalocyanine (CuPc) hybrid multilayers with t = 0, 1, 7, and 10 were investigated by using x-ray photoemission spectroscopy (XPS). Rather sharp interfacial properties were observed in the CuPc films grown on an epitaxial MgO/Fe/MgO(001) trilayer than a MgO/Fe(001) bilayer. This work suggests a new way to improve device performance of organic spintronic devices by utilizing an artificially grown MgO(001) thin layer.

• Journal of Electrical Engineering and information Science
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• v.3 no.1
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• pp.110-116
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• 1998

A single-crystalline epitaxial film of GaAs has been grown on Si using a gs assisted-ionized vapour beam eptaxial technique. The native oxide layer on the silicon substrate was removed at 550$^{\circ}C$ by use of an accelerated arsenic ion beam, instead of a high-temperature desorption. During the growth the substrate temperature was maintained at 550$^{\circ}C$. Transmission electron microscopy and electron diffraction data suggest that the GaAs layer is an epitaxially grown single-crystalline layer. The possibility of growing device quality GaAs on Si is able demonstrated through fabrication of GaAs MODFET on Si substrates.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.164-167
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• 2002

SiC direct bonding technology is very attractive for both SiCOI(SiC-on-insulator) electric devices and SiC-MEMS applications because of its application possibility in harsh environments. This paper presents on pre-bonding according to HF pre-treatment conditions in SiC wafer direct bonding using PECVD oxide. The characteristics of bonded sample were measured under different bonding conditions of HF concentration, and applied pressure. The 3C-SiC epitaxial films grown on Si(100) were characterized by AFM and XPS, respectively. The bonding strength was evaluated by tensile strength method. Components existed in the interlayer were analyzed by using FT-IR. The bond strength depends on the HF pre-treatment condition before pre-bonding (Min : 5.3 kgf/$\textrm{cm}^2$∼Max : 15.5 kgf/$\textrm{cm}^2$).