• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1488-1490
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• 2002

The (Bi,Ba,Sr)$TiO_3$[BBST] thin films were fabricated on Pt/Ti/$SiO_2$/Si substrate by RF sputtering method. We investigated the effects of Ar/$O_2$ rates on the structural properties of BBST thin films. Decreasing the $O_2$ rates, the intensity of $BaBi_4Ti_4O_{15}$ and $Bi_4Ti_3O_{12}$ peaks were increased but the $(Ba_{0.5}Sr_{0.5})TiO_3$ peak was decreased. In the case of BBST thin films deposited with condition of 90/10 (Ar/$O_2$) ratio, the composition of Ba/Sr/Bi was 0.35/0.4/0.25. Also, in the BBST thin films deposited with condition of 80/20(Ar/$O_2$) ratio, the composition of Br,Sr and Ti were relatively uniform. But the component of Bi and Ti were diffused into the Pt layers.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.10
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• pp.752-758
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• 2010

The etching characteristics of indium tin oxide (ITO) thin films in an $O_2/BCl_3/Ar$ plasma were investigated. The etch rate of ITO thin films increased with increasing $O_2$ content from 0 to 2 sccm in $BCl_3$/Ar plasma, whereas that of ITO decreased with increasing $O_2$ content from 2 sccm to 6 sccm in $BCl_3$/Ar plasma. The maximum etch rate of 65.9 nm/m in for the ITO thin films was obtained at 2 sccm $O_2$ addition. The etch conditions were the RF power of 500 W, the bias power of 200 W, the process pressure of 15 mTorr, and the substrate temperature of $40^{\circ}C$. The analysis of x-ray photo electron spectroscopy (XPS) was carried out to investigate the chemical reactions between the surfaces of ITO thin films and etch species.

• Korean Journal of Materials Research
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• v.2 no.5
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• pp.337-342
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• 1992

Spectroscopic diagnostics on reactive plasmas was carried out in a facing target sputtering unit with BaO +12Fe composite targets and 50% $O_2+$ Ar sputter gas. Spectra of rective plasmas were composed of peaks which were assigned to be Ba, B$a^+$, Fe, FeO, F$e^+$, Ar, $Ar^+$, O, $O^+$. As detecting positions in plasmas were far away from targets, the relative peak intensities of the ions and neutral species were decreased, but the relative intensities of the former decreased faster than those of the latter.

• Journal of the Korean Ceramic Society
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• v.32 no.7
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• pp.799-808
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• 1995

Transparent conductive films of aluminium doped zinc oxide (AZO) have been prepared by using the DC magnetron sputtering with the ZnO : Al (Al2O3 2 wt%) oxide target oriented to c-axis. Electrical and optical properties depended upon the O2/Ar gas ratio. The optical transmittance and sheet resistance of the AZO coated glass was 60~65% and 75Ω/$\square$, respectively at the O2/Ar gas ratio of 0. With the increase of the oxygen partial pressure to 2.0$\times$10-2, they were increased to the values of 81% and 1kΩ/$\square$, respectively. The films with the resistivities of 1.2~1.4$\times$10-3 Ω.cm, mobilities of 11~13 $\textrm{cm}^2$/V.sec and carrier concentrations of 3.5$\times$1020~4.0$\times$1020/㎤ were produced at the optimum O2/Ar gas ratio, which was 0.5$\times$10-2~1.0$\times$10-2. According to XRD analysis, the films have only one peak corresponding to the (002) plane, which indicates that there is a strong preferred orientation of the films. The grain size of ZnO films were calculated to 200~320 $\AA$, which was increased with the O2/Ar gas ratio and Ar gas flowrate.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.4
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• pp.298-303
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• 2003

Bi$_4$-$_{x}$EU$_{x}$Ti$_3$O$_{12}$ (BET) thin films were etched by inductively coupled CF$_4$/Ar plasma. We obtained the maximum etch rate of 78 nm/min at the gas mixing ratio of CF$_4$(10%)/Ar(90%). The variation of volume density for F and Ar atoms are measured by the optical emission spectroscopy. As CF$_4$increased in CF$_4$/Ar plasma, the emission intensities of F increase, but Ar atoms decrease, which confirms our suggestion that emission intensity is proportional to the volume density of atoms. From X-ray photoelectron spectroscopy, the intensities of the Bi-O, the Eu-O and the Ti-O peaks are changed. By pure Ar plasma, intensity peak of the oxygen-metal (O-M : TiO$_2$, Bi$_2$O$_3$, Eu$_2$O$_3$) bond was seemed to disappear while the intensity of pure oxygen peak showed an opposite tendency. After the BET thin films was etched by CF$_4$/Ar plasma, the peak intensity of O-M bond increase slowly, but more quickly than that of peak belonged to pure oxygen atoms due to the decrease of Ar ion bombardment. Scanning electron microscopy was used to investigate etching Profile. The Profile of etched BET thin film was over 85$^{\circ}$./TEX>.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.62-65
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• 2001

$SrBi_2Ta_2O_{9}$ thin films were etched in inductively coupled $Cl_{2}$/$CF_{4}$/Ar plasma. The maximum etch rate was 1060 $\AA\textrm{m}$/min in $Cl_{2}$/$CF_{4}$/Ar (80). The chemical reactions on the etched surface were studied with x-ray photoelectron spectroscopy. The etching of SBT thin films in $Cl_{2}$/$CF_{4}$/Ar were etched by chemically assisted reactive ion etching. The small addition of $Cl_2$ into $CF_4$(20)/Ar(80) plasma will decrease the fluorine radicals and the increase Cl radical.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.29-32
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• 2000

Cerium oxide thin film has been proposed as a buffer layer between the ferroelectric film and the Si substrate in Metal-Ferroelectric-Insulator-Silicon (MFIS ) structures for ferroelectric random access memory (FRAM) applications. In this study, CeO$_2$thin films were etched with Cl$_2$/Ar gas combination in an inductively coupled plasma (ICP). The highest etch rate of CeO$_2$film is 230 $\AA$/min at Cl$_2$/(Cl$_2$+Ar) gas mixing ratio of 0.2. This result confirms that CeO$_2$thin film is dominantly etched by Ar ions bombardment and is assisted by chemical reaction of Cl radicals. The selectivity of CeO$_2$to YMnO$_3$was 1.83. As a XPS analysis, the surface of etched CeO$_2$thin films was existed in Ce-Cl bond by chemical reaction between Ce and Cl. The results of XPS analysis were confirmed by SIMS analysis. The existence of Ce-Cl bonding was proven at 176.15 (a.m.u.).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.29-32
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• 2000

Cerium oxide thin film has been proposed as a buffer layer between the ferroelectric film and the Si substrate in Metal-Ferroelectric-Insulator-Silicon (MFIS ) structures for ferroelectric random access memory (FRAM) applications. In this study, CeO$_2$ thin films were etched with Cl$_2$/Ar gas combination in an inductively coupled plasma (ICP). The highest etch rate of CeO$_2$ film is 230 $\AA$/min at Cl$_2$/(Cl$_2$+Ar) gas mixing ratio of 0.2. This result confirms that CeO$_2$ thin film is dominantly etched by Ar ions bombardment and is assisted by chemical reaction of Cl radicals. The selectivity of CeO$_2$ to YMnO$_3$ was 1.83. As a XPS analysis, the surface of etched CeO$_2$ thin films was existed in Ce-Cl bond by chemical reaction between Ce and Cl. The results of XPS analysis were confirmed by SIMS analysis. The existence of Ce-Cl bonding was proven at 176.15 (a.m.u.).

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.12
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• pp.8-13
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• 2001

Cerium oxide ($CeO_2$) thin film has been proposed as a buffer layer between the ferroelectric thin film and the Si substrate in Metal-Ferroelectric-Insulator-Silicon (MFIS) structures for ferroelectric random access memory (FRAM) applications. In this study, $CeO_2$ thin films were etched with $Cl_2$/Ar gas mixture in an inductively coupled plasma (ICP). Etch properties were measured for different gas mixing ratio of $Cl_2$($Cl_2$+Ar) while the other process conditions were fixed at RF power (600 W), dc bias voltage (-200 V), and chamber pressure (15 mTorr). The highest etch rate of $CeO_2$ thin film was 230 ${\AA}$/min and the selectivity of $CeO_2$ to $YMnO_3$ was 1.83 at $Cl_2$($Cl_2$+Ar gas mixing ratio of 0.2. The surface reaction of the etched $CeO_2$ thin films was investigated using x-ray photoelectron spectroscopy (XPS) analysis. There is a Ce-Cl bonding by chemical reaction between Ce and Cl. The results of secondary ion mass spectrometer (SIMS) analysis were compared with the results of XPS analysis and the Ce-Cl bonding was monitored at 176.15 (a.m.u). These results confirm that Ce atoms of $CeO_2$ thin films react with chlorine and a compound such as CeCl remains on the surface of etched $CeO_2$ thin films. These products can be removed by Ar ion bombardment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.73-77
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• 2021

Ga-doped ZnO thin films by RF magnetron sputtering process were synthesized according to the deposition conditions of O2 and Ar atmosphere gases, and rapid heat treatment (RTA) was performed at 600℃ in an N2 atmosphere. The thickness of the deposited ZnO : Ga thin film was measured, the crystal phase was investigated by XRD pattern analysis, and the microstructure of the thin film was observed by FE-SEM and AFM images. The intensity of the (002) plane of the X-ray diffraction pattern showed a significant difference depending on the deposition conditions of the thin films formed by O2 and Ar atmosphere gas types. In the case of a single thin f ilm doped with Ga under O2 conditions, a strong diffraction peak was observed. Under O2 and Ar conditions, in the case of a multilayer thin film with Ga doping, only a peak on the (002) plane with a somewhat weak intensity was shown. In the FE-SEM image, it was observed that the grain size of the surface of the thin film slightly increased as the thickness increased. In the case of a multilayer thin film with Ga doping under O2 and Ar atmosphere conditions, the specific resistance was 6.4 × 10-4 Ω·cm. In the case of a single thin film with Ga doping under O2 atmosphere conditions, the resistance of the thin film decreased. The resistance decreased as the thickness of the Ga-doped ZnO thin film increased to 2 ㎛, showing relatively a low specific resistance of 1.0 × 10-3 Ω·cm.