• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.388-388
• /
• 2010

In this study, Ferroelectric vinylidene fluoride-trifluoroethylene (VF2-TrFE) copolymer films were directly deposited on degenerated Si (n+, $0.002\;{\Omega}{\cdot}cm$) using by spin coating method. A 1~5 wt% diluted solution of purified vinylidene fluoride-trifluoroethylene (VF2:TrFE = 70:30) in a dimethylformamide (DMF) solvent were prepared and deposited on silicon wafers at a spin rate of 2000 ~ 4000 rpm for 2 ~ 30 seconds. After annealing in a vacuum ambient at 100 ~ $200^{\circ}C$ for 60 min, upper aluminum electrodes were deposited by vacuum evaporation for electrical measurement. X-ray diffraction results showed that the VF2-TrFE films on Si substrates had $\beta$-phase of copolymer structures. The capacitance on highly doped Si wafer showed hysteresis behavior like a butterfly shape and this result indicates clearly that the copolymer films have ferroelectric properties. The typical measured remnant polarization ($P_r$) and coercive filed ($E_c$) values were about $5.7\;{\mu}C/cm^2$ and 710 kV/em, respectively, in an applied electric field of ${\pm}$ 1.5 MV/em. The gate leakage current densities measured at room temperature was less than $7{\times}10^{-7}\; A/cm^2$ under a field of 1 MV/cm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.169-170
• /
• 2006

In this study, ultra thin films of ferroelectric vinylidene fluoride-trifluoroethylene (VF2-TrFE) copolymer were fabricated on degenerated Si (n+, $0.002\;{\Omega}{\cdot}cm$) using by spin coating method. A 1~5 wt% diluted solution of purified vinylidene fluoride-trifluoroethylene (VF2:TrFE=70:30) in a dimethylformamide (DMF) solvent were prepared and deposited on silicon wafers at a spin rate of 2000~5000rpm for 30 seconds. After annealing in a vacuum ambient at $200^{\circ}C$ for 60 min, upper gold electrodes were deposited by vacuum evaporation for electrical measurement. X-ray diffraction results showed that the VF2-TrFE films on Si substrates had $\beta$-phase of copolymer structures. The capacitance on $n^+$-Si(100) wafer showed hysteresis behavior like a butterfly shape and this result indicates clearly that the dielectric films have ferroelectric properties. The typical measured remnant polarization (2Pr) and coercive filed (EC) values measured using a computer controlled a RT-66A standardized ferroelectric test system (Radiant Technologies) were about $0.54\;C/cm^2$ and 172 kV/cm, respectively, in an applied electric field of ${\pm}0.75\;MV/cm$.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.43 no.6 s.348
• /
• pp.18-22
• /
• 2006

The inspection of surface properties under n-octadecyltrichlorosilane treated $SiO_2$ film was carried out by current-voltage characteristic and the scanning electron microscope. The voltage at zero current in low electric field is the lowest at 0.3 % OTS treated $SiO_2$ film with hybrid type. $SiO_2$ films changed from inorganic to hybrid or organic properties according to the increase of OTS content. OTS treated $SiO_2$ films with hybrid properties decreased the leakage currents, and the grain size of pentacene deposited sample was also the most small at the hybrid properties. The perpendicular generation of pentacene molecular was related with the surface of insulators. The surface with hybrid properties decreased the grain size, but that with inorganic or organic properties increased the grain size.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.26 no.5
• /
• pp.347-350
• /
• 2013

By inserting a very thin metal layer of Ag between two outer oxide layers of amorphous silicon indium zinc oxide (SIZO), we fabricated a highly transparent SIZO/Ag/SIZO multilayer on a glass substrate. In order to find the optimized thickness of Ag layers, we investigated the variation of optical properties depending on Ag thickness. It was found that the transition of Ag layer from island formation to a continuous film occurred at a critical thickness. Continuity of the Ag film is very important for optical properties in SIZO/Ag/SIZO multilayer. With about 15 nm thick Ag layer, the multilayer showed a high optical transmittance of 80% at 550 nm and low emissivity in IR.

• Transactions on Electrical and Electronic Materials
• /
• v.17 no.4
• /
• pp.201-203
• /
• 2016

Transparent conductive multilayers have been fabricated using transparent amorphous Si doped indium oxide (ISO) semiconductors and metallic Ag of ISO/Ag/ISO. The resistivity of a multilayer is dependent on the middle layer thickness of silver. The thickness of the Ag layer is fixed at 11 nm and takes into account cost and optical transmittance. As-deposited ISO/Ag (11 nm)/ISO multilayer shows a measured resistivity of 7.585×10⁻⁵ Ω cm. After a post annealing treatment of 400℃, the resistivity is reduced to 4.332×10⁻⁵ Ω cm. The reduction of resistivity should be explained that the mobility of the multilayer increased due to the optimized crystalline, meanwhile, the Hall concentration of the multilayer showed an obscure change because the carriers mainly come from the insert of the Ag layer.

• Journal of the Economic Geographical Society of Korea
• /
• v.17 no.2
• /
• pp.349-365
• /
• 2014

Chungcheongbuk-do can be said that it is not developed well because its surface accounts for 7.5% of Korea's whole land surface, and it accounts for 3.1% of population and main economical index from those of whole Korea. However, Chungcheongbuk-do should develop itself more by integrating of Cheongju-si and Cheongwon-gun, transfer of government facilities to Sejong city, and dispersing manufacturing companies of Seoul Metropolitan area. The factor which affects Chungcheongbuk-do's regional specialized industries is the distance from Cheongju-si and Gyeonggi-do. Service industries are specialized in urban area; manufacturing industries are specialized in regions which are close to Cheongju-si or Gyeonggi-do; and primary industries and consumer service industries are specialized in areas that is far from Cheongju-si. This study can be a foundation for studies on regional and industrial change of Chungcheongbuk-do by looking at its population and location quotient.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.9
• /
• pp.1588-1590
• /
• 2007

• Bulletin of the Korean Chemical Society
• /
• v.30 no.2
• /
• pp.467-470
• /
• 2009

• Proceedings of the Korean Magnestics Society Conference
• /
• 2007.05a
• /
• pp.149.2-149.2
• /
• 2007

• Journal of the Korean Vacuum Society
• /
• v.17 no.2
• /
• pp.117-121
• /
• 2008

The SiOC film of carbon centered system was prepared using bistrimethylsilylmethane and oxygen mixed precursor by the chemical vapor deposition. The chemical properties of the SiOC film were analyzed by the I-V measurement and FTIR spectra analysis. The main bond of $950{\sim}1200cm^{-1}$ was composed of the Si-C, Si-O-C and Si-O bonds. The leakage current of the SiOC film increased with the increasing of the carbon content, and the drift of the current was in proportion to the Si-O-C bond content. The deconvoluted data of FTIR spectra could be classified the three types such as organic, hybrid and inorganic types, and the contact angle showed the difference of three types.