• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.209-209
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• 2009

Fabrication of p-type ZnO has already proven difficult and usually inconsistent despite numerous worldwide efforts. Many research groups studied electrical and optical properties P, Li, As, N single doped ZnO thin film. In P-doped ZnO thin film, the reproducibility of p-type conduction with $P_2O_5$ as a dopant source was shown to be relatively poor. In this study, we made P single doped and Li & P co-doped ZnO target. To investigate electrical and optical properties of P single doped and Li & P co-doped ZnO thin film using $P_2O_5$ and $Li_3PO_4$ dopant source respectively was deposited by PLD. The growth temperature was changed 500, $700^{\circ}C$ and various oxygen partial pressure and post-annealing conditions was changed temperature, different gas ambient($O_2,N_2$). We investigate that how to change electrical and optical properties as function of growth temperature, oxygen partial pressure and post-annealing(RTA).

• Journal of Soil and Groundwater Environment
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• v.7 no.2
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• pp.73-81
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• 2002

In normal Fenton's reagent, the reductive mechanism of carbon tetrachloride (CT) with superoxide radical (${O_2}^-$.) was observed and the rate of ${O_2}^-$. production was investigated as a function of $H_2O$$_2$ concentration and pH. As pH was increased, the rate of 1-hexanol degradation was rapidly decreased from 90% (at pH 3) to 5% (at pH 11). On the other hand, more degradation of carbon tetrachloride was observed at higher pH regimes indicating Fenton's reaction is an oxidant-reductant co-existing system at neutral pHs. The rate of $O_2^{-}$ . production was observed at different $H_2$$O_2$ concentrations and at different pHs. The rate increased from (45.3$\pm$7.8) x $10^{-6}$ M/s to (151.0$\pm$26.2) x $10^{-6}$ M/s ($294mM H_2$$O_2$) at pH 11: the rate 3150 increased from (22.1$\pm$3.8) x $10^{-6}$ M/s at pH 7 to (151.0$\pm$26.2) x $^10{-6}$ M/s at pH 11 with 294mM $H_2$$O_2$, These results showed that Fenton's reagent could be applied at wide pH regimes. Especially, carbon tetrachloride, which can not be easily adsorbed to soils and then can be dissolved into groundwater causing a cancer, could be efficiently treated by Fenton's reagent.reagent.

• Korean Journal of Materials Research
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• v.14 no.1
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• pp.67-72
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• 2004

The glass-forming conditions are investigated in the $K_2$O-CaO-$SiO_2$ $-P_2$$O_{5}$ system with 10~65 mole% of$ P_2$$O_{5}$. Thermal properties and dissolution properties were investigated according to variation of the SiO and KO contents in selected compositions. The glass formation condition was determined when $K_2$O/$P_2$$O_{5}$ mole ratio 0~0.24, $SiO_2$/($SiO_2$+$P_2$$O_{5}$ ) mole ratio 0～0.29, and CaO/$P_2$$O_{5}$ mole ratio 0~1.00. In the result of the thermal properties, the glass transition temperature($T_{g}$) and softening temperature($T_{s}$ ) were gradually shifted to the lower temperature range with increase of $K_2$O contents. The maximum value of the chemical durability was shown in $K_2$$PO_2$$O_{5}$ mole ratio 0.17 when the $SiO_2$ contents were changed, and $K_2$O was fixed at 10 mole%. Hence the change of the $K_2$O/$P_2$$O_{5}$ mole ratio was found that a new main factor of the chemical durability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.604-607
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• 2010

The glass formation and the dissolution property in $P_2O_5-K_2O$-FeO-CuO system were studied. In the batch process, the content of P2O5 was fixed at 60mol% and the other elements were varied from 10~40mol%. The prepared glasses were soaked in the D.I. water up to 13hr and the dissolution properties were investigated with the solutions sampled every 2 hr. The result shows that the $P_2O_5$ was leached out firstly from Phosphate glass system and then Cu and Fe ions were observed according to atmosphere change in solution. ICP shows that the dissolution amount in Phosphate was depended on the glass structure and the highest dissolution amount of CuO and FeO ions was observed when the 10mol% $K_2O$ was added in batch process.

• Journal of the Korean Ceramic Society
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• v.35 no.4
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• pp.364-370
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• 1998

Boron-phoshor-silicate glass was fabricated on Si substrates by FHD(Flame Hydrolysis Deposition) The microstructrue of silica soot deposited at various conditon such as composition and substrate temperature was analysed by SEM. After consolidation the refractive index and composition of the silica layer were in-vestigated. For refractive index control B, P and Ge were used as additive elements while B and Ge oxides are easily mixed into $SiO_2$, P oxide($B_2O_3$) doping is difficult because of the volatile property due to low melt-ing point. Boron-phosphorous-silicate glass (BPSG) layer were fabricated using bertical torch and optimized flame temperature substrate temperature and distance of torch and substrate. P concentration of BPSG lay-er measured 3.3 Wt% and the consolidation temperature was lower than $1180^{\circ}C$. The measured refractive index of BPSG silica layer in $1.55\;\mu\textrm{m}$ wavelength was $1.4480{\pm}1{\times}10^{-1}$ and the thickness was $22{\pm}1\;\mu\textrm{m}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.145-146
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• 2006

The most Important research topic in the development of ZnO LED and LD is the production of p-type ZnO thin film that has minimal stress with outstanding stoichiometric ratio. In this study, Phosphorus diffused into the undoped ZnO thin films using the ampoule-tube method for the production of p-type znO thin films. The undoped ZnO thin films were deposited by RF magnetron sputtering system on $GaAs_{0.6}P_{0.4}$/GaP and Si wafers. 4N Phosphorus (P) was diffused into the undoped ZnO thin films in ampoule-tube which was performed and $630^{\circ}C$ during 3hr. We found the diffusion condition of the conductive ZnO films which had p-type properties with the highest mobility of above 532 $cm^2$/Vs compared with other studies PL spectra measured at 10K for the purpose of analyzing optical properties of p-type ZnO thin film showed strong PL intensity in the UV emission band around 365nm ~ 415nm and 365nm ~ 385nm.

• Journal of the Korean institute of surface engineering
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• v.52 no.4
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• pp.187-193
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• 2019

Electroless Ni-P coatings are widely used in the chemical, mechanical, and electronic industries because of their excellent wear and abrasion resistance. In this study, the effect of $TiO_2$ particles of composite coating was investigated. To improve the corrosion resistance, electroless $Ni-P-TiO_2$composite coating was studied by varying the $TiO_2$ content. The morphology and phase structure of $Ni-P-TiO_2$ composite coatings were analyzed by scanning electron microscopy(SEM), X-ray diffractometry(XRD) and X-ray photoelectron spectroscopy(XPS). The result showed that $Ni-P-TiO_2$composite coating is composed of Ni, P, Ti and O. It exhibits an amorphous structure, high hardness and good corrosion resistance to the substrate. $Ni-P-TiO_2$ composite coatings have higher open circuit potential than that of the substrate, which obtained at $TiO_2$ content of 5.0 g/L optimal integrated properties.

• Transactions on Electrical and Electronic Materials
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• v.9 no.1
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• pp.24-27
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• 2008

ZnO has intensively attracted interest for the next generation of short wavelength LEDs and semiconductor lasers. However, for the development and application of the devices based on this material, the fabrication of p-type ZnO thin films is pivotal. Generally, the process of preparation of ZnO is unavoidably accompanied by the natural donor ions such as interstitial Zn ions and oxygen vacancy ions that show n-type electrical property and make fabrication of p-type ZnO to be a hard problem. On this study, to realize stable high-quality p-type ZnO thin films, the undoped ZnO thin films were diffused with P in vapor state. The ZnO:P thin films showed high-quality p-type properties electrically and optically.

• Korean Journal of Microbiology
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• v.12 no.2
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• pp.85-93
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• 1974

Four stereoisomers of inositol p-aminosalicylate, that is hexaris-O-(p-aminosalicylyl)-myo-inositol, hexaris-O-(p-aminosalicylyl)-muco-inositol were synthesized by p-aminosalicylyl chloride with myo-, epi-, scyllo-, and muco-inositol respectively. Their antibacterial activity was tested against human type tubercle bacilli $H_{37}$/Rv, in contrast to 1.25.gamma./ml of p-aminosalicylic acid used as control. Hexaris-O-(p-aminoslicylyl)-muco-inositol showed the strongest antibacterial action at 0.625.gamma./ml, the other compounds more or less active than p-aminosalicylic acid.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.126-129
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• 2001

A p-n junction was obtained by the deposition of an n-type ZnO thin film on a p-type Zn-doped InP substrate. The Zn-doped InP substrate has been made by the diffusion of Zn with sealed ampoule technique. The ZnO deposition process was performed by pulsed laser deposition (PLD). The p-n junction was formed and showed a typical I-V characteristic. We will also discuss about the realization of an ultraviolet light-emitting diode (LED). The structure of n-ZnO/p-Zn-doped InP could be a good candidate for the realization of an ultraviolet light-emitting diode or an ultraviolet laser diode.