ZnO wire-like thin films were synthesized through thermal oxidation of sputtered Zn metal films in dry air. Their nanostructure was confirmed by SEM, revealing a wire-like structure with a width of less than 100 nm and a length of several microns. The gas sensors using ZnO wire-like films were found to exhibit excellent H2 gas sensing properties. In particular, the observed high sensitivity and fast response to H2 gas at a comparatively low temperature of 200˚C would lead to a reduction in the optimal operating temperature of ZnO-based H2 gas sensors. These features, together with the simple synthesis process, demonstrate that ZnO wire-like films are promising for fabrication of low-cost and high-performance H2 gas sensors operable at low temperatures. The relationship between the sensor sensitivity and H2 gas concentration suggests that the adsorbed oxygen species at the surface is O-.

현재 방송 영화 기록물은 수집 관리 체계가 미흡하여 망실의 위험이 상존하고 있다. 또한 수집 관리 기관의 이해관계에 따라 국가 기록물의 접근이 폐쇄적이다. 따라서 영구보존 가치를 지닌 방송프로그램 영화 기록정보 수집관리를 체계화하여, 국가의 역사 문화 기록유산으로 보존 및 활용을 위한 중장기 계획을 수립하여 추진하여야 할 것이다. 본 연구는 선진 국가의 방송 영화 기록물 체계를 비교 분석하여 우리나라 기록물 수집 관리 제도의 문제점을 도출하고 개선 방안을 제시하고자 한다. 연구결과, 방송프로그램의 경우 프랑스와 미국 등은 방송프로그램에 대한 법적 의무납본 및 자발적 납본을 채택하고 전문적인 공공방송영상아카이브를 운영, 안정적으로 수집 관리하고 있다. 영화의 경우엔, 거의 모든 선진 외국이 의무 납본제를 통해 체계적으로 관리하고 있다. 이에 우리나라에서도 총괄 관리 기능을 수행할 독립적인 성격의 국립 방송 영화 아카이브 설립될 필요가 있으며 안정적인 방송영화 기록물의 수집을 위해 의무 납본제를 실시하여 국가기록물의 멸실을 방지해야 할 것이다. 이를 위해서는 법, 제도의 개정이 필수적으로 이루어져야 할 것이다.

Indium Tin Oxide (ITO) thin films on Polyethylene Terephtalate (PET) substrate were prepared by Roll-to-Roll sputter system with targets of 5 wt% and 10 wt% SnO2 at room temperature. The influence of the chromaticity (b*) and transmittance properties of the ITO Films were investigated. The ITO thin films were deposited as a function of the DC power, rolling speed, and Ar/O2 gas flow ratio, and then characterized by spectrophotometer. Their crystallinity and surface resistance were also analyzed by X-ray diffractometer and 4-point probe. As a result, the chromaticity (b*) and transmittance of the ITO films were broadly dependent on the thickness, which was controlled by the rolling speed. When the ITO films were prepared with the DC power of 300 W and the Ar/O2 gas flow ratio of 30/1 sccm using 10 wt% SnO2 target as a function of the rolling speeds 0.01 through 0.10 m/min, its chromaticity (b*) and transmittance were about -4.01 to 11.28 and 75.76 to 86.60%, respectively. In addition, when the ITO films were deposited with the DC power of 400W and the Ar/O2 gas flow ratio of 30/2 sccm used in 5 wt% SnO2 target, its chromaticity (b*) and transmittance were about -2.98 to 14.22 and 74.29 to 88.52%, respectively.

The deposition behavior and structural and magnetic properties of electroless Co-B and Co-Fe-B deposits, as well as the amorphous ribbon substrates, were investigated. These Co-based alloy deposits exhibited characteristic polycrystalline structures and surface morphology and magnetic properties that were dependent on the type of amorphous substrates. The catalytic activity sequence of the amorphous ribbon electrodes for anodic oxidation of DMAB was estimated from the current density-potential curve in the anodic partial electrolytic bath that did not contain the metal ions. Both the deposition rate and potential in the initial region were obtained in order of the catalytic activity, depending on the alloy compositions of the substrates. The deposition rate linearly varied against the deposition time. The initial deposition potential may have also determined the structural and magnetic properties of the deposit based on the thickness of μm order. Furthermore, a basic study of the electroless deposition processes on an amorphous ribbon substrate has been carried out in connection with the structural and magnetic properties of the deposits.

ZnO thin film was grown on a sapphire single crystal substrate by plasma assisted molecular beamepitaxy. In addition to near band edge (NBE) emissions, both blue and green luminescences are also observedtogether. The PL intensity of the blue luminescence (BL) range from 2.7 to 2.9eV increased as the amountof activated oxygen increased, but green luminescence (GL) was weakly observed at about 2.4eV without muchchange in intensity. This result is quite unlike previous studies in which BL and GL were regarded as thetransition between shallow donor levels such as oxygen vacancy and interstitial zinc. Based on the transitionlevel and formation energy of the ZnO intrinsic defects predicted through the first principle calculation, whichemploys density functional approximation (DFA) revised by local density approximation (LDA) and the LDA+Uapproach, the green and blue luminescence are nearly coincident with the transition from the conduction bandto zinc vacancies of V2-Zn and V-Zn, respectively.

In this study we investigated the effect of the multi-step texturing process on the electrical and optical properties of hydrogenated Al-doped zinc oxide (HAZO) thin films deposited by rf magnetron sputtering. AZO films on glass were prepared by changing the H2/(Ar+H2) ratio at a low temperature of 150˚C. The prepared HAZO films showed lower resistivity and higher carrier concentration and mobility than those of non-hydrogenated AZO films. After deposition, the surface of the HAZO films was multi-step textured in diluted HCl (0.5%) for the investigation of the change in the optical properties and the surface morphology due to etching. As a result, the HAZO film fabricated under the type III condition showed excellent optical properties with a haze value of 52.3%.

Mn-substituted BiFeO3(BFO) thin films were prepared by r.f. magnetron sputtering under an Ar/O2mixture of various deposition pressures at room temperature. The effects of the deposition pressure andannealing temperature on the crystallization and electrical properties of BFO films were investigated. X-raydiffraction patterns revealed that BFO films were crystallized for films annealed above 500oC. BFO filmsannealed at 550oC for 5 min in N2 atmosphere exhibited the crystallized perovskite phase. The (Fe+Mn)/Biratio decreased with an increase in the deposition pressure due to the difference of sputtering yield. The grainsize and surface roughness of films increased with an increase in the deposition pressure. The dielectricconstant of BFO films prepared at various conditions shows 127~187at 1kHz. The leakage current densityof BFO films annealed at 500oC was approximately two orders of magnitude lower than that of 550oC. Theleakage current density of the BFO films deposited at 10~30m Torr was about 5×10-6~3×10-2A/cm2 at 100kV/cm. Due to the high leakage current, saturated P-E curves were not obtained in BFO films. BFO film annealedat 500oC exhibited remnant polarization(2Pr) of 26.4µC/cm2 at 470kV/cm.

Changes in the surface morphology and light scattering of textured Al doped ZnO thin films on glasssubstrates prepared by rf magnetron sputtering were investigated. As-deposited ZnO:Al films show a hightransmittance of above 80% in the visible range and a low electrical resistivity of 4.5×10-4Ω·cm. The surfacemorphology of textured ZnO:Al films are closely dependent on the deposition parameters of heater temperature,working pressure, and etching time in the etching process. The optimized surface morphology with a cratershape is obtained at a heater temperature of 350oC, working pressure of 0.5 mtorr, and etching time of 45seconds. The optical properties of light transmittance, haze, and angular distribution function (ADF) aresignificantly affected by the resulting surface morphologies of textured films. The film surfaces, havinguniformly size-distributed craters, represent good light scattering properties of high haze and ADF values.Compared with commercial Asahi U (SnO2:F) substrates, the suitability of textured ZnO:Al films as frontelectrode material for amorphous silicon thin film solar cells is also estimated with respect to electrical andoptical properties.

SnxSe100-X (15|X|30) alloys have been studied to explore their suitability as phase change materials for nonvolatile memory applications. The phase change characteristics of thin films prepared by a Radio Frequency (RF) magnetron co-sputtering system were analyzed by an X-ray diffractometer and 4-point probe measurement. A phase change static tester was also used to determine their crystallization under the pulsed laser irradiation. X-ray diffraction measurements show that the transition in sheet resistance is accompanied by crystallization. The amorphous state showed sheet resistances five orders of magnitude higher than that of the crystalline state in SnxSe100-X (x = 15, 20, 25, 30) films. In the optimum composition, the minimum time of SnxSe100-X alloys for crystallization was 160, 140, 150, and 30ns at 15mW, respectively. The crystallization temperature and the minimum time for crystallization of thin films were increased by increasing the amount of Sn, which is correlated with the activation energy for crystallization.

In this report, the structural and optical properties of sol-gel derived MgxZn1-xO thin films upon changes in the composition and annealing temperature were investigated. The Mg2+ content and the annealing temperature were varied in the range of 0≤x≤0.35 and 400˚C≤T≤600˚C, respectively. The films exhibited a hexagonal wurtzite structure of a polycrystalline nature. The optical transmittance exceeded 85% and the optical band gap of the film was tuned as high as 3.84 eV at a value of x = 0.35 (annealed at 400˚C), which was evidently the maximum Mg2+ content for the single-phase polycrystalline MgxZn1-xO thin films prepared in this experiment. The optical band gap and photoluminescence emission were tailored to the higher energy side while maintaining crystallinity without a significant change of the lattice constant.

Behaviors of saturated fatty acid halides (CI4, C16, C18) were measured by LB method when the molecules were stimulated by pressure. The saturated fatty acid halides were deposited on the indium tin oxide(lTO) glass by the LB method. The average organic ultra thin film size and the surface roughness of the fatty acid halides thin films were investigated using AFM. It was found that AFM images show small surface roughness (2.5~5.0 nm) and the organic ultra thin film size of 2.5~12 nm. Both aggregations and pin-holes were also seen on the AFM images. However we found that the surface roughness. These effects seem to be reasonable to be related to the increase of the organic ultra thin film size of fatty acid halides.

Transparent Sn-doped In2O3 (ITO) single-layer and ITO/Au/ITO multilayer films were deposited onglass substrates by reactive magnetron sputtering to compare the properties of the films. They were thenannealed in a vacuum of 1×10-2 Pa at temperatures ranging from 150 to 450oC for 20 min to determinethe effect of the annealing temperature on the properties of the films. As-deposited 100nm thick ITO filmsexhibit a sheet resistance of 130Ω/□ and optical transmittance of 77% at a wavelength length of 550nm. Byinserting a 5nm-thick Au layer in ITO/metal/ITO (IMI) films, the sheet resistance was decreased to as lowas 20Ω/□ and the optical transmittance was decreased to as little as 73% at 550nm. Post-deposition annealingof ITO/Au/ITO films led to considerably lower electrical resistivity and higher optical transparency. In the X-ray diffraction pattern, as-deposited ITO films did not show any diffraction peak, whereas as-deposited ITO/Au/ITO films have Au (222) and In2O3 (110) crystal planes. When the annealing temperature reached the 150- 450oC range, the both diffraction peak intensities increased significantly. A sheet resistance of 8Ω/□ and anoptical transmittance of 82% were obtained from the ITO/Au/ITO films annealed at 450oC.

The effect of annealing under argon atmosphere on hydrogenated amorphous silicon (a-Si:H) thin films deposited at room temperature and 300˚C using Radio Frequency (RF) magnetron sputtering has been investigated. For the films deposited at room temperature, there was not any increase in hydrogen content and optical band gap of the films, and as a result, quality of the films was not improved under any annealing conditions. For the films deposited at 300˚C, on the other hand, significant increases in hydrogen content and optical band gap were observed, whereas values of microstructure parameter and dark conductivity were decreased upon annealing below 300˚C. In this study, it was proposed that the Si-HX bonding strength is closely related to deposition temperature. Also, the improvement in optical, electrical and structural properties of the films deposited at 300˚C was originated from thermally activated hydrogen bubbles, which were initially trapped at microvoids in the films.

Nano-crystalline hydroxyapatite (HAp) films were formed at the Ti surface by a single-step microarc oxidation (MAO), and HAp-zirconia composite (HZC) films were obtained by subsequent chemical vapor deposition (CVD) of zirconia onto the HAp. Through the CVD process, zero- and one-dimensional zirconia nanostructures having tetragonal crystallinity (t-ZrO2) were uniformly distributed and well incorporated into the HAp crystal matrix to form nanoscale composites. In particular, (t-ZrO2) was synthesized at a very low temperature. The HZC films did not show secondary phases such as tricalcium phosphate (TCP) and tetracalcium phosphate (TTCP) at relatively high temperatures. The most likely mechanism for the formation of the t-ZrO2 and the pure HAp at the low processing temperature was proposed to be the diffusion of Ca2+ ions. The HZC films showed increasing micro-Vickers hardness values with increases in the t-ZrO2 content. The morphological features and phase compositions of the HZC films showed strong dependence on the time and temperature of the CVD process. Furthermore, they showed enhanced cell proliferation compared to the TiO2 and HAp films most likely due to the surface structure change.

Modified thermal annealing was applied to the activation of the polycrystalline silicon films doped as p-type through implantation of B2H6. The statistical design of experiments was successfully employed to investigate the effect of rapid thermal annealing on activation of polycrystalline Si doped as p-type. In this design, the input variables are furnace temperature, power of halogen lamps, and alternating magnetic field. The degree of ion activation was evaluated as a function of processing variables, using Hall effect measurements and Raman spectroscopy. The main effects were estimated to be furnace temperature and RTA power in increasing conductivity, explained by recrystallization of doped ions and change of an amorphous Si into a crystalline Si lattice. The ion activation using rapid thermal annealing is proven to be a highly efficient process in low temperature polycrystalline Si technology.

We fabricated 10 nm-TiO2 thin films for DSSC (dye sensitized solar cell) electrode application using ALD (atomic layer deposition) method at the low temperatures of 150˚ and 250˚. We characterized the crosssectional microstructure, phase, chemical binding energy, and absorption of the TiO2 using TEM, HRXRD, XPS, and UV-VIS-NIR, respectively. TEM analysis showed a 10 nm-thick flat and uniform TiO2 thin film regardless of the deposition temperatures. Through XPS analysis, it was found that the stoichiometric TiO2 phase was formed and confirmed by measuring main characteristic peaks of Ti 2p1, Ti 2p3, and O 1s indicating the binding energy status. Through UV-VIS-NIR analysis, ALD-TiO2 thin films were found to have a band gap of 3.4 eV resulting in the absorption edges at 360 nm, while the conventional TiO2 films had a band gap of 3.0 eV (rutile)~3.2 eV (anatase) with the absorption edges at 380 nm and 410 nm. Our results implied that the newly proposed nano-thick TiO2 film using an ALD process at 150˚ had almost the same properties as thsose of film at 250˚. Therefore, we confirmed that the ALD-processed TiO2 thin film with nano-thickness formed at low temperatures might be suitable for the electrode process of flexible devices.

Cellulose nanofibers from microfibril cellulose (MFC) was prepared by hydrobromic acid (HBr) treatment at different concentrations. Polyvinyl alcohol (PVA) composite films at various loading level of nanofibers were manufactured by a film casting method. The analysis of degree of polymerization (DP), crystallinity (Xc) and molecular weight (Mw) of cellulose after acid treatment was conducted. The mechanical and thermal properties of the cellulose nanofibers reinforced PVA films were characterized using tensile tests and thermogravimetric analysis (TGA). The DP and Mw of MFC by HBr hydrolysis considerably decreased, but Xc showed no significant change. After acid hydrolysis, the diameter of cellulose nanofibers was in the range of 100 to 200 nm. The thermal stability of the films was steadily improved with the increase of nanofiber loading. There was a significant increase in the tensile strength of PVA composite films with the increase in MFC loading. Finally, 5 wt.% nanofiber loading exhibited the highest tensile strength and thermal stability of PVA composite films.

본 연구에서는 poly(acrylonitrile-butadiene-styrene) (ABS)에 carbon graphite와 zeolite 4A를 첨가하여 복합 필름을 제조하고 공기와 수증기 투과 특성을 살펴보았다. 복합 필름의 경우 모든 경우에서 순수한 ABS에 비해서 산소와 질소의 투과도가 감소하였으며, 산소의 투과도 감소가 질소의 투과도 감소보다 약간 큰 관계로 산소/질소 선택도도 조금 감소하였다. 또한, 수증기 투과도도 순수한 ABS에 비해서 약 1/2로 감소하였다. 이러한 투과도의 감소는 ABS에 filler를 첨가함으로 인하여 물질 확산 경로의 tortuosity가 증가했기 때문인 것으로 생각된다.

The effects of an addition of ZrO2 on the microstructure and electrical properties of MgO films as a protective layer for AC plasma display panels were investigated. MgO + a 200 ppm ZrO2 protective layer prepared by e-beam evaporation exhibited a secondary electron emission coefficient (γ) that was improved by 21% compared to that of a pure MgO protective layer. The relative density and Vickers hardness increased with a further addition of ZrO2. These results suggest that the discharge properties and optical properties of MgO protective layers are closely related to the relative density and Vickers hardness. The good optical and electrical properties of γ, at 0.080, a grain size of 19 μm and an optical transmittance of 91.93 % were obtained for the MgO + 200 ppm ZrO2 protective layer sintered at 1700˚C for 5 hrs.

Ba(Ti,Sn)O3 thin films, for use as dielectrics for MLCCs, were grown from Sn doped BaTiO3 sourcesby e-beam evaporation. The crystalline phase, microstructure, dielectric and electrical properties of films wereinvestigated as a function of the (Ti＋Sn)/Ba ratio. When BaTiO3 sources doped with 20~50mol% of Sn wereevaporated, BaSnO3films were grown due to the higher vapor pressure of Ba and Sn than of Ti. However, itwas possible to grow the Ba(Ti,Sn)O3 thin films with ≤15mol% of Sn by co-evaporation of BTS and Ti metalsources. The (Ti＋Sn)/Ba and Sn/Ti ratio affected the microstructure and surface roughness of films and thedielectric constant increased with increasing Sn content. The dielectric constant and dissipation factor ofBa(Ti,Sn)O3 thin films with ≤15mol% of Sn showed the range of 120 to 160 and 2.5~5.5% at 1KHz,respectively. The leakage current density of films was order of the 10−9~10−8A/cm2 at 300KV/cm. The researchresults showed that it was feasible to grow the Ba(Ti,Sn)O3 thin films as dielectrics for MLCCs by an e-beamevaporation technique.