• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.78-81
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• 2002

Ferroelectric thin film is a very attractive material for the tunable microwave device applications such as electronically tunable mixers, delay lines, filters and phase shifters. Thin films of $Pb_{x}Sr_{1-x}TiO3(PST)$ were fabricated onto Pt/Ti/SiO2/Si substrate by the sol-gel method. We have investigated the structural and dielectric properties of PST(50/50) thin films for tunable microwave device applications. The PST thin films show typical polycrystalline structure with a dense microstructure without secondary phase formation. Dielectric properties of PST films are strongly dependent on annealing temperature. The dielectric constants, loss and tunability of the PST (50/50) thin films were 404, 0.023 and 51.73 %, respectively.

• 전기학회논문지
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• 제59권6호
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• pp.1083-1086
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• 2010

The $Sr_{0.7}Bi_{2.3}Nb_2O_9$ thin films were deposited on Si substrate using RF magnetron sputtering method. And the SBN thin films were annealed at 650~800$[^{\circ}C$]. The surface rougness showed about 0.42[nm] in annealed thin film at $650[^{\circ}C$]. The dielectric constant(150) of SBN thin film was obtained by annealing temperature above $700[^{\circ}C$]. The voltage dependence of dielectric loss showed a value within 0.02 in voltage ranges of -10~＋10[V]. The dielectric constant characteristics showed a stable value with the increase of frequency. Also, the SBN thin films annealed at $750[^{\circ}C$] showed a fatigue-free characteristics up to $1.0\times10^8$ cycles.

• 한국전기전자재료학회논문지
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• 제17권9호
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• pp.947-952
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• 2004

Tb-doped lead zirconate titanate(Pb(Zr$\_$0.6/,Ti$\_$0.4/)O$_3$; PZT) thin films on Pt(111)/Ti/SiO$_2$/Si(100) substrates were fabricated by the sol-gel method. The effect on the structural and electrical properties of films measured according to Tb content. The dielectric and ferroelectric properties of Tb-doped PZT thin films were altered significantly by Tb-doping. The PZT thin film with higher dielectric constant and improved leakage current characteristic was obtained by adding 0.3 mol% Tb. The relative dielectric constant and the dielectric loss of the 0.3 mol% Tb-doped PZT thin film were 1611 and 0.024, respectively. Typical value of the swichable remanent poaraization(2Pr) and the coercive filed of the PZT film capacitor for 0.3 mol% Tb-doped were 61.4 ${\mu}$C/cm$^2$ and 61.9 kV/cm, respectively. Tb-doped PZT thin films showed improved fatigue characteristics comparing to the undoped PZT thin film.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.150-153
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• 1996

Polyvinylidene fluoride(PVDF) thin films are fabricated by vapor deposition method and their dielectric characteristics are investigated. At electric field near 4MV/m, a phase transition occur with polar ${\alpha}$ . In accordance to increasing temperature, the dielectric relaxation of PVOF thin films show from 70Hz to 104Hz. This result correspond to Debye's theory[1]. Activation energy of PVDP thin film is 21Kca1/mo1.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.547-549
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• 2001

The dielectric constants and dielectric losses of ZrTiO$_4$thin films deposited by DC magnetron reactive sputtering were investigated. The paraelectric properties were measured in the 100kHz range. As the deposition temperature increased (up to 67$0^{\circ}C$), the dielectric losses (tan$\delta$) decreased (down to 0.017$\pm$0.007), while the dielectric constants ($\varepsilon$) were in the range of 35$\pm$7. Post annealing at 80$0^{\circ}C$ in oxygen for 2h reduced tan$\delta$ down to 0.005$\pm$0.001, higher than those of well-sintered bulk ZrTiO$_4$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.743-745
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• 2002

Pyroelectric and dielectric properties of modified PZT thin film and bulk ceramics were studied. In case of bulk specimens were prepared by conventional ceramic process and thin films with same composition and (111) preferred orientation were prepared by the sol-gel process. Their crystal structure, pyroelectric and dielectric properties were investigated after poling at $150^{\circ}C$ for 30 min for bulk ceramics and no poling treatment, respectively. Dielectric constants and losses of bulk and thin film were 600, 875 and 0.028, 0.025, respectively. Pyroelectric coefficients obtained were $50nC/cm^2K$ and $30nC/cm^2K$, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.155-158
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• 2002

Eu-doped lead zirconium titanate $Pb_{1.1}(Zr_{0.3}Ti_{0.7})O_{3}$ thin films on the Pt/Ti/$SiO_2$/Si substrates prepared by a metalorganic decomposition (MOD) method. The effect on the structural and electrical properties of the films measured according to Eu content. Eu-doping altered significantly the dielectric and ferroelectric properties. The remanent polarization and coercive field decreased with increasing the concentration of Eu content. The dielectric constant and dielectric loss of the film decreased with increasing Eu contents. The 3 mol% of Eu-doped PZT thin film showed large remanent polarization and the fatigue characteristic of the film did not change up to $10^9$ switching cycles.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.229-229
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• 2007

In this study, HEMA-based hydrophilic copolymers were synthesized and dielectric constant (K) of the polymer thin films were investigated by change hydroxyl group (-OH) ratio in the polymer chain. The different hydroxyl group ratios were characterized by FT-IR and its thin films were obtained by spin coating. As a result, due to the moisture absorption of the hydrophilic thin film, the dielectric constant has been increased as was expected. The highest dielectric constant (K=4.19, @1MHz) was observed at 40% hydroxyl group ratio among the several polymers.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.381-381
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• 2010

$(ZrO_2)_{0.66}(HfO_2)_{0.34}$ thin films as gate dielectrics have been proposed to overcome the problems of tunneling current and degradation mobility inachieving a thin equivalent oxide thickness. An extremely thin $SiO_2$ layer is used in order to separate the carrier in MOSFET channel from the dielectric field fluctuation caused by phonons in the dielectric which decreases the carrier mobility. The electronic and optical properties influenced the device performance to a great extent. $(ZrO_2)_{0.66}(HfO_2)_{0.34}$ dielectric films on p-Si (100) were grown by atomic layer deposition method, for which the conduction band offsets, valence band offsets and band gapswere obtained by using X-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The band gap, valence and conduction band offset values for $(ZrO_2)_{0.66}(HfO_2)_{0.34}$ dielectric thin film, grown on Si substrate were about 5.34, 2.35 and 1.87 eV respectively. This band alignment was similar to that of $ZrO_2$. In addition, The dielectric function (k, $\omega$), index of refraction n and the extinction coefficient k for the $(ZrO_2)_{0.66}(HfO_2)_{0.34}$ thin films were obtained from a quantitative analysis of REELS data by comparison to detailed dielectric response model calculations using the QUEELS-$\varepsilon$(k, $\omega$)-REELS software package. These optical properties are similar with $ZrO_2$ dielectric thin films.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.335-337
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• 1995

In this study, $Pb(Zr_{0.52}Ti_{0.48})O_3$ ceramic thin films were fabricated from an alkoxide-based by Sol-Gel method. $Pb(Zr_{0.52}Ti_{0.48})O_3$ stock solution was made and spin-coated on the $Pt/SiO_2/Si$ substrate at 4000[rpm] for 30[sec]. Coated specimens were dried at 400[$^{\circ}C$] for 10 [min]. The coating process was repeated 4 times and then heat-treated at 500$\sim$800[$^{\circ}C$], 1 hour. The final thickness of the thin films were about 3000[A]. The crystallinity and microstructure of the thin films were investigated for varing the sintering condition. The ferroelectric perovskite' phases precipitated under the sintering of 700[$^{\circ}C$] for 1 hours. In the $Pb(Zr_{0.52}Ti_{0.48})O_3$ thin films sintered at 700[$^{\circ}C$] for 1 hour, dielectric constant and dielectric loss were 2133, 2.2[%] at room temperature, respectively. $Pb(Zr_{0.52}Ti_{0.48})O_3$ thin film capacitors having good dielectric and electrical properties are expected for the application to the dielectric material of DRAM.