• Korean Journal of Materials Research
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• v.19 no.8
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• pp.437-442
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• 2009

This paper describes an improved strategy for controlling the adhesion force using both the antiadhesion and adhesion layers for a successful large-area transfer process. An MPTMS (3-mercaptopropyltrimethoxysilane) monolayer as an adhesion layer for Au/Pd thin films was deposited on Si substrates by vapor self assembly monolayer (VSAM) method. Contact angle, surface energy, film thickness, friction force, and roughness were considered for finding the optimized conditions. The sputtered Au/Pd ($\sim$17 nm) layer on the PDMS stamp without the anti-adhesion layer showed poor transfer results due to the high adhesion between sputtered Au/Pd and PDMS. In order to reduce the adhesion between Au/Pd and PDMS, an anti-adhesion monolayer was coated on the PDMS stamp using FOTS (perfluorooctyltrichlorosilane) after $O_2$ plasma treatment. The transfer process with the anti-adhesion layer gave good transfer results over a large area (20 mm $\times$ 20 mm) without pattern loss or distortion. To investigate the applied pressure effect, the PDMS stamp was sandwiched after 90$^{\circ}$ rotation on the MPTMS-coated patterned Si substrate with 1-${\mu}m$ depth. The sputtered Au/Pd was transferred onto the contact area, making square metal patterns on the top of the patterned Si structures. Applying low pressure helped to remove voids and to make conformal contact; however, high pressure yielded irregular transfer results due to PDMS stamp deformation. One of key parameters to success of this transfer process is the controllability of the adhesion force between the stamp and the target substrate. This technique offers high reliability during the transfer process, which suggests a potential building method for future functional structures.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.545-545
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• 2008

Poly-Si is an essential material for floating gate in NAND Flash memory. To fabricate this material within region of floating gate, chemical mechanical polishing (CMP) is commonly used process for manufacturing NAND flash memory. We use colloidal silica abrasive with alkaline agent, polymeric additive and organic surfactant to obtain high Poly-Si to SiO2 film selectivity and reduce surface defect in Poly-Si CMP. We already studied about the effects of alkaline agent and polymeric additive. But the effect of organic surfactant in Poly-Si CMP is not clearly defined. So we will examine the function of organic surfactant in Poly-Si CMP with concentration separation test. We expect that surface roughness will be improved with the addition of organic surfactant as the case of wafering CMP. Poly-Si wafer are deposited by low pressure chemical vapor deposition (LPCVD) and oxide film are prepared by the method of plasma-enhanced tetra ethyl ortho silicate (PETEOS). The polishing test will be performed by a Strasbaugh 6EC polisher with an IC1000/Suba IV stacked pad and the pad will be conditioned by ex situ diamond disk. And the thickness difference of wafer between before and after polishing test will be measured by Ellipsometer and Nanospec. The roughness of Poly-Si film will be analyzed by atomic force microscope.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.335-335
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• 2007

본 연구에서는 RF Magnetron Sputtering 법으로 94:6 wt%의 비율로 Sb가 첨가된 $SnO_2$ 타겟을 사용하여 실온에서 ATO(Antimony doped Tin Oxide) 박막을 증착하고, 열처리가 ATO 박막의 구조적, 전기적, 광학적 특성에 미치는 효과를 연구하고자 하였다. ATO 박막의 두께는 약 200 nm로 증착하였으며, 실험 조건으로는 Ar 유량을 100 seem, 진공도는 1, 5, 10 mTorr로 변화시켰으며 스퍼터링 파워는 100, 150, 200, 250 W로 조절하였다. 증착되어진 박막은 vacuum 상태에서 300, $600^{\circ}C$의 온도에서 열처리를 수행하였으며 결과적으로 스퍼터링 파워가 증가함에 따라 비저항이 감소하였고, 250 W의 파워와 10 mTorr의 공정압력 조건에서 $600^{\circ}C$로 열처리한 ATO 박막은 $5{\times}10^{-3}{\Omega}-cm$의 저항률과 85.3%의 높은 투과도를 가지는 우수한 투명 전도막을 얻을 수 있었다.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.75-79
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• 1996

The purpose of this study was to investigate the effect of vitamin {TEX}$B_{6}${/TEX} deficiency on the utilization and recuperation of stored fuel in exercising rats. Thirty six rats were fed either a vitamin {TEX}$B_{6}${/TEX} deficient diet(-{TEX}$B_{6}${/TEX}) or a control diet(+{TEX}$B_{6}${/TEX}) for 5 weeks, then subdivided into 3 group: non-exercise group(NE), exercise group(EX), exercise and recuperation group(EX). EX group were exercised in treadmill({TEX}$10^{o}${/TEX}, 0.5~0.8km/h)for 2 hours and ER group were recuperated three days with the respective diet after exercise. Glucose(GLU), glycogen(GLY), protein(PRO), trigyceride(TG) and free fatty acid(FFA) were compared in plasma(P), liver(L) and skeletal muscle(M) of rats. Compared to +{TEX}$B_{6}${/TEX} rats, in NE group, the level of L-GLY of -{TEX}$B_{6}${/TEX} rats was higher, M-TG, L-PRO of -{TEX}$B_{6}${/TEX} rats were lower and there were no differences in P-PRO, P-FFA, P-TG, M-GLY, M-PRO and L-TG. In EX group, the levels of P-FFA, L-PRO of -{TEX}$B_{6}${/TEX} rats were higher. P-TG, L-TG of -{TEX}$B_{6}${/TEX} rats were lower and there was no difference in L-GLY. In EG group, the levels of P-GLU, P-PRO, P-RG, L-PRO of -{TEX}$B_{6}${/TEX} rats were lower and there were no differences in L-GLY, L-TG, M-TG and M-GLY. these results suggest that a lowered intake of vitamin {TEX}$B_{6}${/TEX} may impair the recuperation of aminals after exercise related to exercise fuel stores although there is a compensation among stored fuel utilization during exercise.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.496-503
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• 2021

Background: Considering the expenses of and difficulties in arsenic speciation by high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS), alternative measurement methods should be useful, especially for large-scale research and projects. Objectives: A measurement method was developed for arsenic speciation using HPLC-atomic fluorescence spectrometry (HPLC-AFS) as an alternative to HPLC-ICP-MS. Methods: Total arsenic and toxic arsenic species in some seafoods were determined by atomic absorption spectrometry coupled with hydride vapor generation (AAS-HVG) and HPLC-AFS, respectively. Recovery rate of arsenic species in seafood was evaluated by ultra sonication, microwave and enzyme (pepsin) for the optimal extraction method. Results: Limits of detection of HPLC-AFS for As³⁺, dimethylarsinate (DMA), monomethylarsonate (MMA) and As⁵⁺ were 0.39, 0.53, 0.60 and 0.64 ㎍/L, respectively. The average accuracy ranged from 97.5 to 108.7%, and the coefficient of variation was in the range of 1.2~16.7%. As³⁺, DMA, MMA and As⁵⁺ were detected in kelp, the sum of toxic arsenic in kelp was 40.4 mg/kg. As³⁺, DMA, MMA and As⁵⁺ were not detected in shrimp and squid, but total arsenic (iAS and oAS) content in shrimp and squid analyzed by AAS-HVG were 18.1 and 24.7 mg/kg, respectively. Conclusions: HPLC-AFS was recommendable for the quantitative analysis method of arsenic species. As toxic arsenic species are detected in seaweeds, further researches are needed for the contribution degree of seafood in arsenic exposure.

• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.95-102
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• 2022

Since the organic light-emitting diodes (OLEDs) have been widely investigated as next-generation displays, it has been successfully commercialized as a flexible and rollable display. However, there is still wide room and demand to improve the device characteristics such as power efficiency and lifetime. To solve this issue, there has been a wide research effort, and among them, the internal and the external light extraction techniques have been attracted in this research field by its fascinating characteristic of material independence. In this study, a micro-nano composite structured external light extraction layer was demonstrated. A reactive ion etching (RIE) process was performed on the surfaces of hexagonally packed hemisphere micro-lens array (MLA) and randomly distributed sphere diffusing films to form micro-nano composite structures. Random nanostructures of different sizes were fabricated by controlling the processing time of the O₂ / CHF₃ plasma. The fabricated device using a micro-nano composite external light extraction layer showed 1.38X improved external quantum efficiency compared to the reference device. The results prove that the external light extraction efficiency is improved by applying the micro-nano composite structure on conventional MLA fabricated through a simple process.

• Journal of Periodontal and Implant Science
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• v.53 no.1
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• pp.2-19
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• 2023

Purpose: Surgical techniques in orthodontics have received widespread attention in recent years. Meanwhile, biomaterials with high molecular content have been introduced, such as platelet concentrates (PCs), which may accelerate orthodontic tooth movement (OTM) and reduce periodontal damage. The present systematic review aimed to answer the following PICO question: "In patients in whom orthodontic surgical techniques are performed (P), what is the effectiveness of using PCs over the surgical site (I) when compared to not placing PCs (C) to achieve faster tooth movement (O)?" Methods: A search was performed in 6 databases. The criteria employed were those described in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses declaration. The present review included studies with a control group that provided information about the influence of PCs on the rate of OTM. Results: The electronic search identified 10 studies that met the established criteria. Conclusions: The included studies were very diverse, making it difficult to draw convincing conclusions. However, a tendency was observed for OTM to be accelerated when PCs were used as an adjuvant for canine distalization after premolar extraction when distalization was started in the same session. Likewise, studies seem to indicate an association between PC injection and the amount of canine retraction. However, it is not possible to affirm that the use of PCs in corticotomy shortens the overall treatment time, as this question has not been studied adequately.

• Journal of Animal Science and Technology
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• v.66 no.1
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• pp.93-102
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• 2024

This study investigated the effect of dietary supplementation with phytase on growth performance, fecal excretion, and compost nutrition on broilers fed available phosphorus (avP)- and calcium (Ca)-deficient diets. A total of 750 one-day-old broiler chicks were randomly divided into five dietary groups having ten replications in a floor house. Diets of the groups were formulated with positive control (PC), negative control (NC; low avP and Ca), and NC supplemented with phytase levels; 500 (NC500), 1,000 (NC1000), and 1,500 FTU/kg (NC1500). A three-phase feeding program was used in the trial. Average daily gain (ADG) and average daily feed intake (ADFI) in the groups fed diets supplemented with phytase were significantly (p < 0.05) higher than those fed NC and the increase was equivalent to those fed PC. Serum levels of Ca and phosphorus (P) were higher (p < 0.05) in broilers fed NC1000 and NC1500 than in those fed NC. Interleukin (IL) level was the lowest in the group fed NC. Plasma myo-inositol (INS) concentrations in the NC1500 group were higher (p < 0.05) than PC, NC, and NC500 groups. Crude protein (CP) excretion was notably (p < 0.05) lower in the NC1500 group than in PC and NC groups. A lower (p < 0.05) concentration of P₂O₅ was observed in compost from the group fed NC1500 than the groups fed PC and NC. Accordingly, we suggest that phytase supplementation in lower avP and Ca levels of broiler diet can improve their productive performance and reduce environmental pollution.

• Journal of Chest Surgery
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• v.27 no.2
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• pp.99-113
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• 1994

Pentastarch is a new synthetic hydroxyethyl starch similar to hetastarch. We report on the clinical comparisons the clinical efficacy and safety of 10% pentastarch in prime solutions for CPB in cardiac operations with that of 20% serum albumin. During CPB, group P [n = 20] received 500ml of 10% pentastarch and group A [n = 20] received 100ml of 20% albumin in prime solutions The postoperative time of ICU stay in group P and the day and amount of chest drain, hospital stay in group A were longer [p<0.05]. Fresh whole blood and PRBC were added only in group A and a higher amount of hartman solution was added in group A during CPB [p<0.05]. Prothrombin time was prolonged preoperatively and 2 days postoperatively in group A and 7 days postoperatively in group P [p<0.05] but there were no significant differences in bleeding time or fibrinogen level. Platelet count was higher immediately postoperatively in group A and preoperatively and 1, 2, and 7 days postoperatively in group P [p<0.05].Total protein and albumin level were higher 1 day postoperatively in group A and 2 and 7 days postoperatively in group P [p<0.05]. BUN was increased 2 days postoperatively in group A and Cr was increased 1 day postoperatively in group P [p<0.05]. CPK was higher preoperatively and 1, 2, and 7 days postoperatively in group A and plasma hemoglobin level was also higher 2 and 7 days postoperatively in group A [p<0.05]. There were no significant differences in arterial blood gas analysis but higher pO2 and lower pCO2 levels were maintained in group P and ejection fraction was higher 7 days postoperatively in group P [p<0.05]. Both groups were improved postoperatively in NYHA class and the hemodynamic parameters such as MAP, CO, CI, SV, LVSWI were well maintained in group P [p<0.05]. The amount of blood products used was higher in group A and urine output was higher immediately postoperatively in group A and 1, 2 days postoperatively in group P and the chest output was higher in group A. The complications were developed in 7 patients in group A and 5 patients in group P and mortality was not present in both groups.In conclusion, 10% pentastarch is as safe and effective as 20% albumin in prime solutions for cardiopulmonary bypass in cardiac operations.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.159-167
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• 2002

The purpose of this study was to evaluate the efficacy and safety depending on the route of flumazenil, as an antagonist against midazolam. The subjects of this study were 15 volunteers of $22{\sim}24$ years old. They were sedated with midazolam 0.2mg/Kg intranasal spray, and then 40 minutes after midazolam administration, they were given flumazenil 0.2mg intranasal spray for their reversal. For evaluation of the efficacy and safety of intranasal spray for flumazenil, they were monitored with pulse-oxymeter(Nellcor symphony N-3000, Nellcor Puritan CO. USA) and electric sphygmomanometer (Heartcare 200, National CO. Japan), and were assessed themselves using visual analogue scale(VAS) for tranquilization, sleep, fatigue and attitude. All of these subjects were reduced completely without any undesired situations. The results from this study can be summarized as follows ; 1. Nasaly administered flumazenil using spray device produced much more rapid reduction than intravenously administered flumazenil, but soon after fell in more deep sedated state than intravenously administered flumazenil. 2. There were no considerable side effects or bad influence on vital signs of both nasaly administered flumazenil and intravenously administered flumazenil. These results suggested that the flumazenil administered nasaly using spray device for reversal, we could treat patients safely and effectively under conscious sedation using midazolam administration. But, We will have to research about its optimal dosages for flumazenil, used as intranasal spray for reversal agents against the midazolam by evaluating the blood plasma concentration of midazolam and flumazenil.