• Journal of the Semiconductor & Display Technology
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• v.18 no.4
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• pp.120-123
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• 2019

The effect of surface plasmon on ZTO thin films was investigated. The phenomenon of depletion occurring in the interface of the ZTO thin film created a potential barrier and the dielectric layer of the depletion formed a non-mass particle called plasmon. ZTO thin film represents n-type semiconductor features, and surface current by plasma has been able to obtain the effect of improving electrical efficiency as a result of high current at positive voltage and low current at negative voltage. It can be seen that the reduction of electric charge due to recombination of electronic hole pairs by heat treatment of compound semiconductors induces higher surface current in semiconductor devices.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.167-167
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• 2011

Magnetic random access memory (MRAM) is one of the prospective semiconductor memories for next generation. It has the excellent features including nonvolatility, fast access time, unlimited read/write endurance, low operating voltage, and high storage density. MRAM consists of magnetic tunnel junction (MTJ) stack and complementary metal-oxide semiconductor (CMOS). The MTJ stack is composed of various magnetic materials, metals, and a tunneling barrier layer. For the successful realization of high density MRAM, the etching process of magnetic materials should be developed. Among various magnetic materials, FePt has been used for pinned layer of MTJ stack. The previous etch study of FePt magnetic thin films was carried out using $CH_4/O_2/NH_3$. It reported only the etch characteristics with respect to the variation of RF bias powers. In this study, the etch characteristics of FePt thin films have been investigated using an inductively coupled plasma reactive ion etcher in various etch chemistries containing $CH_4$/Ar and $CH_4/O_2/Ar$ gas mixes. TiN thin film was employed as a hard mask. FePt thin films are etched by varying the gas concentration. The etch characteristics have been investigated in terms of etch rate, etch selectivity and etch profile. Furthermore, x-ray photoelectron spectroscopy is applied to elucidate the etch mechanism of FePt thin films in $CH_4$/Ar and $CH_4/O_2/Ar$ chemistries.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.118-118
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• 2011

The Nano-Floating Gate Memory(NFGM) devices with ZnO:Cu thin film embedded in Al2O3 and AlOx-SAOL were fabricated and the electrical characteristics were evaluated. To further improve the scaling and to increase the program/erase speed, the high-k dielectric with a large barrier height such as Al2O3 can also act alternatively as a blocking layer for high-speed flash memory device application. The Al2O3 layer and AlOx-SAOL were deposited by MLD system and ZnO:Cu films were deposited by ALD system. The tunneling layer which is consisted of AlOx-SAOL were sequentially deposited at $100^{\circ}C$. The floating gate is consisted of ZnO films, which are doped with copper. The floating gate of ZnO:Cu films was used for charge trap. The same as tunneling layer, floating gate were sequentially deposited at $100^{\circ}C$. By using ALD process, we could control the proportion of Cu doping in charge trap layer and observe the memory characteristic of Cu doping ratio. Also, we could control and observe the memory property which is followed by tunneling layer thickness. The thickness of ZnO:Cu films was measured by Transmission Electron Microscopy. XPS analysis was performed to determine the composition of the ZnO:Cu film deposited by ALD process. A significant threshold voltage shift of fabricated floating gate memory devices was obtained due to the charging effects of ZnO:Cu films and the memory windows was about 13V. The feasibility of ZnO:Cu films deposited between Al2O3 and AlOx-SAOL for NFGM device application was also showed. We applied our ZnO:Cu memory to thin film transistor and evaluate the electrical property. The structure of our memory thin film transistor is consisted of all organic-inorganic hybrid structure. Then, we expect that our film could be applied to high-performance flexible device.----못찾겠음......

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.162-167
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• 2012

Edible biopolymer films were developed from hijiki ($Hizikia$ $fusiforme$), using a high-pressure homogenization (HPH). Effects of pressure and pass number of HPH on color, tensile, moisture barrier properties, flavor profiles, and microstructure of hijiki films were investigated. A hydrocolloid of hijiki was processed by HPH at 69, 103, or 152 MPa with 1, 2, or 3 passes. A hijiki-base film was formed by drying a film-forming solution which was prepared by mixing of the HPH-processed suspension with glycerol and Polysorbate 20. Tensile strength and elastic modulus increased with increasing HPH pressure. Uniformity of the films increased as the pressure of HPH with 1 pass increased and the number of pass increased at 152 MPa. Water vapor permeability ($2.1-3.3g{\cdot}mm/kPa{\cdot}h{\cdot}m^2$) and water solubility (0.4-1.0%), which are relatively low compared to those of many other edible films, show the potential that hijiki-base films are applied to the range of low to intermediate moisture food as wrapping or coating.

• Polymer(Korea)
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• v.37 no.2
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• pp.225-231
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• 2013

Poly(vinyl alcohol) (PVA) hybrid films containing 5 wt% pristine clay mineral were synthesized in the water solution. The various PVA hybrid films were synthesized from structurally different pristine clays: saponite (SPT), montmorillonite (MMT), hectorite (SWN), hydrophilic bentonite (PGV), and mica (Mica). The thermo-optical properties and morphologies of the PVA hybrid films were evaluated with various pristine clays. The nanostructure of the hybrid films was observed using transmission electron microscopy, which showed that the clay layers were well dispersed into the matrix polymer, although some clusters or agglomerated particles were also detected. The addition of pristine clay was more effective with regard to improving the thermal properties and gas barrier characteristics, whereas the optical transparency of the PVA hybrid films deteriorated with pristine clay.

• Journal of the Korean institute of surface engineering
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• v.51 no.4
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• pp.224-230
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• 2018

In this study, Mg films were prepared on hot dip aluminized steel (HDA) by using a sputtering method as a high corrosion resistance coating. The corrosion resistance of the Mg films was improved by controlling the morphology and the crystal structure of films by adjusting the Ar gas pressure during the coating process. Anodic polarization measurement results confirm that the corrosion resistance of the Mg films was affected by surface morphology and crystal structure. The corrosion resistance of the Mg coated HDA specimen increased with decreasing crystal size of the Mg coating and it was also improved by forming a film with denser morphology. The crystal structure oriented at Mg(101) plane showed the best corrosion resistance among crystal planes of the Mg metals, which is attributed to its relatively low surface energy. Neutral salt spray test confirmed that corrosion resistance of HDA can be greatly improved by Mg coating, which is superior to that of HDG (hot dip galvanized steel). The reason for the improvement of the corrosion resistance of Mg films on hot dip aluminized steel was due to the barrier effect by the Mg corrosion products formed by the corrosion of the Mg coating layer.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.340-340
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• 2002

In an effort to develop alternative single buffer layer technology for YBa$_2$Cu$_3$O$_{7-{\delta}}$ (YBCO) coated conductors, we have investigated both LaMnO$_3$, (LMO) and La$_2$Zr$_2$O$_{7}$ (LZO) as potential buffer layers. High-quality LMO films were grown directly on textured Ni and Ni-W (3%) substrates using rf magnetron sputtering. Highly textured LZO buffers were grown on textured Ni substrates using sol-gel alkoxide processing route. YBCO films were then grown on both LMO and LZO buffers using pulsed laser deposition. Detailed X-ray studies have shown that YBCO films were grown on both LMO and LZO layers with a single epitaxial orientation. A high J$_{c}$ of over 1 MA/cm$^2$ at 77 K and self-field was obtained on YBCO films grown on both LMO-buffered Ni or Ni-W substrates, and also on LZO-buffered Ni substrates. We have identified LaMnO$_3$ as a good diffusion barrier layer for Ni and it also provides a good template for growing high current density YBCO films. Similarly we have also demonstrated the growth of high J$_{c}$ YBCO films on all solution buffers. We will discuss in detail about our buffer deposition processes. processes.s.s.s.s.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.230-233
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• 1995

Using Polyimide Langmuir-Blodgett(LB) films as a tunneling barrier, Current -Voltage(I-V) characteristics and inelastic electron tunneling spectroscoupy(IETS) of the junctions incorporating 1-layer orgainc monolayer were invesgated. Several peaks originating in vibrational modes of constituted molecules of 1-layer monolayers were clearly observed in the IET spectra.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.339-339
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• 2015

타이타늄을 2단계로 양극산화하여 색을 유지하며 표면에 튜브형태를 갖는 산화막을 제조하였다. 타이타늄을 양극산화 시, 전해질 농도, 양극산화 전압, 시간 등에 따라 다양한 색을 띄게 되는데, 기름기 등의 오염물질로 인한 색 변화, 내 지문성 등의 문제가 유발된다. 이에 타이타늄을 양극산화하여 나노튜브를 성장시킨 후, 기존 산화막 제조와 같은 조건으로 다시 양극산화하였다. 그 결과 기존 barrier 형태의 산화막 색이 구현되면서, 표면의 돌기형태에 따른 접촉각이 변화하게 되었다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.4
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• pp.541-546
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• 1990

The current conduction and dielectric breakdown properties of oxide grown on phosphorous-doped polysilicon have been investigated by means of the ramped I-V measurements. The effective barrier heights of polyoxide grown by different silicon deposition and oxidation conditions were calculated from the Fowler-Nordheim tunneling characteristic. The average critical fields were also obtained for each film. From the results, the high temperature oxided polyoxide grown on amorphous silicon film shows superior electrical characteristics comparing to the other films.