• 한국표면공학회지
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• 제29권6호
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• pp.839-846
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• 1996

Epitaxial (La, Sr)$CoO_3/Pb(Zr,\;Ti)O_3/(La,\;Sr)CoO_3$by pulsed laser deposition for ferroelectric field effect transistor. Epitaxial $LaCoO_3/Pb(Zr,\;Ti)O_3/(La,\;Sr)CoO_3$ heterostructures exhibited 70$\mu C/cm^2$ and 17 $\mu C/cm^2$at a positively and negatively poled states, respectively. On the other hand, epitaxial (La, Sr)$CoO_3/Pb(Zr,\;Ti)O_3/LaCoO_3$heterostructures show the remnant polarization states opposite to the $LaCoO_3/Pb(Zr,\;Ti)O_3/(La,\;Sr)CoO_3$ heterostructures. This indicates that the interface between (La, Sr)$CoO_3$ (LSCO) and $Pb(Zr, Ti)O_3(PZT)$ layers affects the asymmetric polarization remanence through electrochemical nature. The resistivity of $LaCoO_3$ (LCO) layer was found to be dependent on an ambient oxygen, primarily the ambient oxygen pressure during deposition. The resistivity of the LCO layer varied in the range of 0.1-100 $\Omega$cm. It is suggested that, with an appropriate resistivity of the LCO layer, the LCO/PZT/LSCO heterostructure can be used as the ferroelectric field effect transistor.

• 한국전기전자재료학회논문지
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• 제16권8호
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• pp.657-662
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• 2003

This paper presents a new fabrication method of selective SiGe epitaxial growth at 650 $^{\circ}C$ on (100) silicon wafer with oxide patterns by reduced pressure chemical vapor deposition. The new method is characterized by a cyclic process, which is composed of two parts: initially, selective SiGe epitaxy layer is grown on exposed bare silicon during a short incubation time by SiH$_4$/GeH$_4$/HCl/H$_2$system and followed etching step is achieved to remove the SiGe nuclei on oxide by HCl/H$_2$system without source gas flow. As a result, we noted that the addition of HCl serves not only to reduce the growth rate on bare Si, but also to suppress the nucleation on SiO$_2$. In addition, we confirmed that the incubation period is regenerated after etching step, so it is possible to grow thick SiGe epitaxial layer sustaining the selectivity. The effect of the addition of HCl and dopants incorporation was investigated.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.104-104
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• 2003

RF magnetron sputtering 법을 이용하여 LaA1O$_3$, SrTiO$_3$, MgO 단결정 기판 위에 BaTiO$_3$ 박막을 에피텍셜하게 증착하여 박막의 특성과 마이크로 웨이브에서의 유전특성을 평가하였다. 각 기판위에 증착한 박막의 격자상수와 FWHM을 조사하였고, pole figure로 에피텍셜 성장을 관찰하였다. 각 시편에 상부 전극으로 interdigital 타입의 전극을 photolithography 하여 캐패시턴스와 tan $\delta$을 조사하였다. 각 기판의 변화에 따른 격자상수 변화와 유전 특성의 변화를 고찰하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 춘계종합학술대회
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• pp.627-630
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• 2002

Bi$_2$Sr$_2$CuOx(Bi-2201) thin films were fabricated by atomic layer-by-layer deposition using an ion bean sputtering method. 10 wt% and 90 wt% ozone mired with 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.

• 전자공학회논문지A
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• 제31A권4호
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• pp.63-69
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• 1994

The Ultrahigh Vacuum Electron Cyclotron Resonance Chemical Vapor Deposition(UHV-ECRCVD) system whose base pressure is 1${\times}10^{9}$ torr has been constructed. In-situ cleaning prior to the epitaxial growth was carried out at 56$0^{\circ}C$ by ECR generated uniform hydrogen plasma whose density is $10^{10}/cm{3}$. The natural oxide was effectively removed without damage by applying positive DC bias(+10V) to the substrate. RHEED(Reflection High Energy Electron Diffraction) analysis has been used to confirm the removal of the surgace oxide and the streaky 2$\times$1 reconstruction of the Si surface, and the suppression of the substrate damage is anaylized by X-TEM(cross-sectional Transmission Electron Microscopy). Surface cleaning technique by ECR hydrogen plasma confirmed good quality epitaxial growth at low temperature.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.471-475
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• 2000

P-type (100) Si wafer patterned with 1000$\AA$ SiO$_2$island was used as substrate and the Si films were deposited under low pressure using Si$_2$H$_{6}$-H$_2$gas mixture where the total gas flow rate and deposition pressure were 16.6sccm and 3.5mtorr, respectively. In this condition, we selectively obtained high-quality epitaxial Si layer of the 350~1050$\AA$ thickness. In order to extend the incubation period, we kept high pressure H$_2$ environment without Si$_2$H$_{6}$ gas for few minutes after first incubation period and then we conformed the existence of second incubation period.iod.

• E2M - 전기 전자와 첨단 소재
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• 제16권9호
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• pp.63.2-64
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• 2003

Epitaxial yttrium-stabilized HfO$_2$ thin films were deposited on p-type (100) Si substrates by pulsed laser deposition at a relatively lower substrate temperature of 550. Transmission electron microscopy observation revealed a fixed orientation relationship between the epitaxial film and Si; that is, (100)Si.(100)HfO$_2$ and [001]Si/[001]HfO$_2$. The film/Si interface is not atomically flat, suggesting possible interfacial reaction and diffusion, X-ray photoelectron spectrum analysis also revealed the interfacial reaction and diffusion evidenced by Hf silicate and Hf-Si bond formation at the interface. The epitaxial growth of the yttrium stabilized HfO$_2$ thin film on bare Si is via a direct growth mechanism without involoving the reaction between Hf atoms and SiO$_2$ layer. High-frequency capacitance-voltage measurement on an as-grown 40-A yttrium-stabilized HfO$_2$ epitaxial film yielded an dielectric constant of about 14 and equivalent oxide thickness to SiO$_2$ of 12 A. The leakage current density is 7.0${\times}$ 10e-2 A/$\textrm{cm}^2$ at 1V gate bias voltage.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2006년도 춘계학술발표회 초록집
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• pp.136-136
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• 2006

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.11.1-11.1
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• 2007

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 추계 학술발표강연 및 논문개요집
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• pp.88-88
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• 2001