• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.73-76
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• 2001

We deposited epitaxial $Ba_{0.6}Sr_{0.4}TiO_{3}(BST)$ films having thickness of 400 nm on MgO(001) substrates, where a 10 nm thick $Ba_{1-x}Sr_{x}TiO_{3}$ (x = 0.1 - 0.7) interlayer was inserted between BST and MgO to manipulate the stress of the BST films. Since the main difference of those epitaxial BST films was the lattice constant of the interlayers, we were very successful in controlling the stress of the BST films. BST films under small tensile stress showed larger dielectric constant than that without stress as well as those under compressive stress. Stress relaxation was investigated using epitaxial BST films with various thicknesses grown on different interlayers. For BST films grown on $Ba_{0.7}Sr_{0.3}TiO_{3}$ interlayers, the critical thickness was about 600 nm. On the other hand, the critical thickness of single-layer BST film was less than 100 nm.

• Macromolecular Research
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• v.17 no.6
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• pp.436-440
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• 2009

We improved the performance of pentacene-based thin film transistors by changing the curing environment of poly(4-vinylphenol) (PVP) gate dielectrics, while keeping the dielectric constant the same. The field-effect mobility of the pentacene TFTs constructed using the vacuum cured PVP was higher than that of the device based on the Ar flow cured gate dielectric, possibly due to the higher crystalline perfection of the pentacene films. The present results demonstrated that the curing conditions used can markedly affect the surface energy of polymer gate dielectrics, thereby affecting the field-effect mobility of TFTs based on those dielectrics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.73-76
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• 2001

We deposited epitaxial $Ba_{0.6}$S $r_{0.4}$Ti $O_3$(BST) films having thickness of 400 nm on MgO(001) substrates, where a 10 nm thick $Ba_{1-x}$S $r_{x}$Ti $O_3$(x=0.1-0.7) interlayer was inserted between BST and MgO to manipulate the stress of the BST films. Since the main difference of those epitaxial BST films was the lattice constant of the interlayers, we were very successful in controlling the stress of the BST films. BST films under small tensile stress showed larger dielectric constant than that without stress as well as those under compressive stress. Stress relaxation was investigated using epitaxial BST films with various thicknesses grown on different interlayers. For BST films grown on $Ba_{0.7}$S $r_{0.3}$Ti $O_3$ interlayers, the critical thickness was about 600 nm. On the other hand, the critical thickness of single-layer BST film was less than 100 nm.00 nm.m.m.m.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.132-136
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• 2009

SiOC thin film of hybrid-type that is the limelight as low dielectric material of next generation were deposited by plasma enhanced chemical vapor deposition (PECVD) method with bistrimethylsilylmethane (BTMSM) precursor increased by 2 sccms from 24 sccms to 32 sccm. Manufactured samples are analyzed components by measuring FT/IR absorption lines. It is a tendency that seems to be growing of Si-O-Si(C) bonding group and narrowing of Si-O-$CH_3$ bonding group relative to the increasing flow-rate BTMSM. The chemical shift in the XPS analysis was shown in the specimens between the BTMSM=26 sccm and BTMSM = 28 sccm. The binding energy of Si 2p, C 1s and O 1s electron orbit spectra was the low-est at the specimen of the BTMSM=26 sccm. From the results of electrical Properties using the 1 MHz C - V measurements, the dielectric constant was 2.32 at the specimen with the BTMSM = 26 sccm.

• Korean Journal of Materials Research
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• v.33 no.4
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• pp.115-123
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• 2023

In this paper, we report and discuss the semi-permanently hydrophilic (SPH) treatment of polyester fabric using plasma polymerization and oxidation based on atmospheric pressure dielectric barrier discharge (APDBD) technology. SiO_xC_y(-H) was coated on polyester fabric using Hexamethylcyclotrisiloxane (HMCTSO) as a precursor, and then plasma oxidation was performed to change the upper layer of the thin film to SiO₂-like. The degradation of hydrophilicity of the SPH polyester fabrics was evaluated by water contact angle (WCA) and wicking time after repeated washing. The surface morphology of the coated yarns was observed with scanning electron microscopy, and the presence of the coating layer was confirmed by measuring the Si peak using energy dispersive x-ray spectroscopy. The WCA of the SPH polyester fabric increased to 50 degrees after 30 washes, but it was still hydrophilic compared to the untreated fabric. The decrease in hydrophilicity of the SPH fabric was due to peeling of the SiO_xC_y(-H) thin film coated on polyester yarns.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1744-1746
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• 1999

In this paper, we give pressure stimulation into organic ultra thin films and detected the induced displacement current properties, and then manufacture a device under the accumulation condition. In processing of a device manufacture, we can see the process is good from the change of a surface pressure and transfer ratio of area per molecule of organic ultra thin films. The structure of manufactured device is MIM(Au/polyimide LB films/AU), the number of accumulated 19 layers. I-V characteristic of the device is measured from -5[V] to +5[V]. The maximum value of measured current is increased as the number of accumulated layers are decreased. The insulation of a thin film is better as the interval between electrodes is larger, and the insulation properties of a thin film is better as the distance between electrodes is larger.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.114-118
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• 1989

Due to the increased integration density of VLSI circuits a highly reliable thin oxide film is required to fabricate a small geometry MOS device. The behavior of thermal $SiO_2$ under high electric field and current condition has a major effect on MOS device degration and also the practical use of MOS device under irradiation has cause the degration of thin oxide films. In this paper, in order to evaluate the reliability of thin oxides with no stress applied and stressed by the irradiation under low electric field, the tests of TDDB (Time-dependent-dielectric breakdown) are used. Failure times against electric field are examined and acceleration factor is obtained for each case. Based on the experimental data, breakdown wear out limitation for thin oxide films is characterised.

• Journal of Integrative Natural Science
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• v.3 no.4
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• pp.219-225
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• 2010

On the surface of mesoporous silica thin films (MSTF) which were fabricated by sol-gel approach there are existences of water and three different silanol types including chained, germinal and isolated silanol. Their amounts changes as a function of aging time of used sol solution, as confirmed by FT-IR. The adsorbed water generates ionic carriers such as H+ and OH- and passivates the Si dangling bonds at the interface of silicon wafer-MSTF. The ionic carriers can not only transport across the thickness of thin film to enhance the leakage current but also diffuse toward the silicon wafer-MSTF interface to depassivate Si dangling bonds. On the other hand, chained silanols or germinal silanols promote the moisture adsorption of MSTF and tend to form strongly hydrogen bonded systems with adsorbed water molecules resulting in very high dielectric constant. Isolated silanol, on the contrary, affects less on electrical properties of thin film.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.509-512
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• 1999

Ferroelectric Sr$_2$(Nb, Ta)$_2$O$_{7}$(SNTO), La$_2$Ti$_2$O$_{7}$(LTO) thin films were prepared by sol-gel processes. SNTO, LTO thin films were spin-coated on Pt/TiO$_2$/SiO$_2$/Si(100). Pt/Ti/SiO$_2$/Si(100). PT/ZrO$_2$/SiO$_2$/Si(100) substrates. After multiple coating, dried thin films were heat-treated for decomposition of residual organics and crystallization. Dielectric and other relevant electrical properties were measured and the results showed a little possibility in ferroelectric gate random access memory devices.ces.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1434-1436
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• 1996

In this study, ferroelectric $PbTiO_3$ thin films were deposited on the Pt/$SiO_2$/Si substrate by Sol-Gel method. $PbTiO_3$ stock solution was made and spin-cooled at 4000[rpm] for 30[sec.]. Coated specimens were dried at $400[^{\circ}C]$ for 10[min.] and then annealed at $500{\sim}800[^{\circ}C]$ for 1 hour. Annealing temperature were examined to optimize micro structural and dielectric properties of the films. The ferroelectric perovskite phase was observed in the file annealed at $700[^{\circ}C]$ for 1 hour. In the case of $PbTiO_3$ thin films annealed at $700[^{\circ}C]$ for hour, dielectric constant and dielectric loss showed the good value of 324, 2.0[%], respectively.