• Journal of Magnetics
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• v.5 no.4
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• pp.143-146
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• 2000

In this study, the magnetic properties of CoCrPt films (far longditudinal recording) on a novel VMn underlayer were measured and compared with similar films on conventional Cr underlayers. It was found that the VMn film had (200) preferred orientation and the lattice constant was about 0.2967 nm, which is slightly larger than that of the Cr film, 0.2888 m. The grain size of the VMn film was 9.8 nm at 30 m thickness, about 39% smaller than that of a similarly deposited Cr. The CoCrPt/VMn films showed higher coercivity in comparison with the CoCrPt/Cr films. The coercivity increase is attributed to the increased Co (11.0) texture, improved lattice matching between Co (11.0) and VMn (200), and lower stacking fault density. V or Mn must have diffused into the CoCrPt magnetic layer uniformly rather than preferentially along grain boundaries. This reduced Ms at higher substrate temperature.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1297-1302
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• 2012

The interaction between carbon monoxide (CO) and a cobalt-salen complex (Co(salen)) was studied and applied to detect CO. The metal complex doped PEDOT:PSS film exhibited good sensitivity to CO and differentiate CO from other gases. The response of the composite to CO was reversible (RSD < 5%) change in resistance upon removal of CO gas from the test chamber. The effects of adding Co(salen) in the probe film on the response of the sensor were investigated using AFM, XPS, and FT-IR spectroscopy. The sensitivity of the sensor increased as the Co(salen) concentration enhanced as it increased from 0.0 to 1.5 wt. %, where the highest sensitivity ($%{\Delta}R/R_o$) of $-25.0{\pm}0.05%$ was achieved with 1.0 wt. % Co(salen). The sensor containing probe exhibited a linear response ($R^2$ = 0.983) in the range of 0.5 to 10.0% CO (v/v) $N_2$, and the detection limit was 1.74% CO (v/v) in $N_2$.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.68-75
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• 2022

The breathable film refers to a high-functional film that allows gas and water vapor to pass through very fine and sophisticated pores but not liquid. In this research, the breathable film was prepared based on linear low-density polyethylene (LLDPE) and CaCO₃ particles by extrude method. The LLDPE composite film containing CaCO₃ particles had excellent mechanical properties and functionalties. The drawing is a technologically simple and excellent method for improving the mechanical properties of composite films. In this work, the effects of draw ratio on morphology, crystallinity, pore size distribution, mechanical properties, and water vapor permeability of the films were examined. The results revealed that both surface morphology and breathability were affected by the influence of chain orientation and crystal growth with increasing the draw ratio. The mechanical properties were improved with increasing the draw ratio.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.9
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• pp.1347-1356
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• 2022

In this paper, we investigate the properties of CoGe thin film-based galvanic cells as a function of their dimension (cell length, width, etc.) and show their application as sensors to Arduino-based IoT sensor networks to detect water contact. Because these CoGe thin film-based galvanic cells do not require mechanical strains or temperature gradients unlike piezoelectric and thermoelectric energy harvesters, we think that these thin film-based galvanic cells are more suitable for self-powered sensor networks demanding sustainable and robust energy harvesters. In the past, a sputter-deposited CoGe thin film has not been intensively investigated for energy harvesting appilcations. Thus, in this study, we perform a feasibility study of galvanic cells composed of a sputter-deposited CoGe thin film to see if they can be applied as potential self-powered sensors. We believe that this paper will be of great help in developing even more enhanced sensor networks.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.91-95
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• 2012

ZnO thin films were deposited on p-type 4H-SiC substrate by pulsed laser deposition. ZnO nanowires were formed on p-type 4H-SiC substrate by furnace. Ti/Au electrodes were deposited on ZnO thin film/SiC and ZnO nanowire/SiC structures, respectively. Structural and crystallographical properties of the fabricated ZnO thin film/SiC and ZnO nanowire/SiC structures were investigated by field emission scanning electron microscope and X-ray diffraction. In this work, resistance and sensitivity of ZnO thin film/SiC gas sensor and ZnO nanowire/SiC gas sensor were measured at $300^{\circ}C$ with various CO gas concentrations (0%, 90%, 70%, and 50%). Resistance of gas sensor decreases at CO gas atmosphere. Sensitivity of ZnO nanowire/SiC gas sensor is twice as big as sensitivity of ZnO thin film/SiC gas sensor.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.339.1-339.1
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• 2014

In this paper we studied the application of inter-poly dielectric as silicon dioxide-like film was deposited by the higher energy assisting deposition (HEAD) process the modified CCP process, which enables low temperature (LT) process and improving film density. In these experiments the relative hydrogen concentration of $SiO_2$-like films deposited on silicon substrate were analyzed by the secondary ion mass spectroscopy (SIMS) and it was shown that our lower hydrogenated oxide (LHO) film prepared by HEAD process with the precursor contained the siloxane species had lower hydrogen concentration, $8{\times}10{\cdot}^{22}cm{\cdot}^3$ than that of the commercial undoped silicon glass (USG) film ($1{\times}10{\cdot}^{21}cm{\cdot}^3$) prepared by the high density plasma-chemical vapor deposition (HDP-CVD). We consider that the LHO film deposited by HEAD process used as high performance material into Flash memory devices.

• Journal of the Semiconductor & Display Technology
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• v.5 no.2 s.15
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• pp.47-49
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• 2006

Various methods of making thin film is being used in semiconductor manufacturing process. The most common method in this field includes CVD(Chemical Vapor Deposition) and PVD(Physical Vapor Deposition). Thin film is deposited on both the backside and the frontside of wafers. The thin film deposited on the backside has poor thickness profile, and can contaminate wafers in the following processes. If wafers with the thin film remaining on the backside are immersed in batch type process tank, the thin film fall apart from the backside and contaminate the nearest wafer. Thus, it is necessary to etch the backside of the wafer selectively without etching the frontside, and chemical injection nozzle positioned under the wafer can perform the backside etching. In this study, the backside chemical injection nozzle with optimized chemical injection profile is built for single wafer tool. The evaluation of this nozzle, performed on $Si_3N_4$ layer deposited on the backside of the wafer, shows the etching rate uniformity of less than 5% at the etching rate of more than $1000{\AA}$.

• Food Science and Preservation
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• v.19 no.6
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• pp.799-806
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• 2012

This experiment was conducted to establish the optimum conditions for high $CO_2$ gas treatment in combination with a proper gas-permeable packaging film to maintain the quality of fig fruit (Ficus carica L). Among the fig fruits with different high $CO_2$ treatments, the quality change was most effectively controlled during storage in the 70%-$CO_2$-treated fig fruit. Harvested fig fruit was packaged using microperforated oriented polypropylene (MP) film to maintain the optimum gas concentrations in the headspace of packaging for the modified-atmosphere system. MP film had an oxygen transmission rate of about $10,295cm^3/m^2$/day/atm at $25^{\circ}C$. The weight loss, firmness, soluble-solid content (SSC), acidity (pH), skin color (Hunter L, a, b), and decay ratio of the fig fruits were monitored during storage at 5 and $25^{\circ}C$. The results of this study showed that the OPP film, OPP film + 70% $CO_2$, and MP film+70% $CO_2$ were highly effective in reducing the loss rate, firmness and decay occurrence rate of fig fruits that were packaged with them during storage. In the case of using treatments with packages of OPP film and OPP film+70% $CO_2$, however, adverse effects like package bursting or physiological injury of the fig may occur due to the gas pressure or long exposure to $CO_2$. Therefore, the results indicated that MP film containing 70% $CO_2$ can be used as an effective treatment to extend the freshness of fig fruits for storage at a proper low temperature.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.3
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• pp.94-98
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• 2014

$LiCoO_2$ thin film has received diverse attention as cathodes material of thin-film micro-batteries. In this study, $LiCoO_2$ thin films were synthesized on Au substrates by sol-gel spin coating method and an annealing process. Their structures were studied using X-ray diffraction and Raman Spectroscopy. The particle morphologies of these thin films were observed by Scaning electron microscope. From the results of X-ray diffractometry and Raman Spectroscopy analyses, it was found that as-grown films had the structure of spinel (LT-$LiCoO_2$) and layered-Rock-salt (HT-$LiCoO_2$) at $550^{\circ}C$ and $750^{\circ}C$ respectively. The annealed films at $650^{\circ}C$ were presumed to be the mixed state of these two types. Throlugh the scanning electron microscope, It was estimated that the particle size in as-grown films at $750^{\circ}C$, were larger crystilline particle than in those at the other lower temperature and well distributed in the film.

• Journal of the Korean Vacuum Society
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• v.16 no.2
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• pp.110-115
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• 2007

A plasma enhanced atomic layer deposition(PEALD) system has been constructed adopting an inductively coupled plasma(ICP) source with an ALD system, and its plasma generation was carried out. Cobalt thin films were deposited on a p-type Si(100) wafer at $230^{\circ}C$. $Co_{2}(CO)_{6}$ was used as a cobalt precursor, $NH_{3}$ as a reactant, and Ar as a carrier and purge gas. The properties of the thin films were investigated using field emission scanning electron microscopy(FESEM) and auger electron spectroscopy(AES). Large amounts of impurities were found in both the ALD film and the PEALD film, however, the amount of impurities in the PEALD film was reduced to about 50 % compared to that in the ALD film. It was found that $NH_{3}$ plasma, very effectively, induces the reaction with carbon in a cobalt precursor.