비정질 Se 광도전 타겟을 이용한 고감도 HARP 촬상관의 제작 및 특성

박욱동,김기완,Kubota, M.,Suzuki, S.,Katoh, T.,Tanioka, K. 경북대학교 센서기술연구소 1997 센서技術學術大會論文集 Vol.8 No.1

A high sensitivity HARP(High-gain Avalanche Rushing amorphous Photoconductor) image pickup tube using 4 μm thick amorphous Se photoconductive target was fabricated and its characteristics were investigated. When the target voltage was increased more than 360 V, the signal current increases rapidly and the dark current of the target was suppressed at 3.2 nA up to the voltage of 490 V. And the peak spectral response of the target was obtained at the wavelength of 460 nm. Also the amplitude response of the HARP tube was 7.5% at 800 TV lines, and the decay lag was 3.4%.

ZnS:SmF₃박막전계발광소자의 제작 및 특성

박욱동,배승춘,김기완 동양대학교 산업기술연구소 2000 東洋大學校 産業技術硏究所 論文集 Vol.2 No.1

A red colored thin film electroluminescent(TFEL) device was fabricated with a ZnS:SmF3 phosphor layer and BST insulating layers. The BST thin film was deposited on ITO coated glass substrate by RF magnetron sputtering method using a target of Ba0.5Sr0.5TiO3. The thickness of ZnS:SmF3 thin film, upper and lower BST insulating layer for a TFEL device were 500nm, 400nm, and 200nm, respectively. The ZnS:SmF3 TFEL device showed that the threshold voltage and maximum brightness of a TFEL device were 160Vrms and 125cd/㎡, respectively.

PLT 절연층을 이용한 ZnS:Mn TFEL소자의 제조 및 특성

박욱동,박경빈,박재현,김영진,최병진,김기완 경북대학교 센서기술연구소 1995 센서技術學術大會論文集 Vol.6 No.1

Thin film electroluminescent(TFEL) device has been fabricated using ZnS:Mn phosphor and PLT insulator. The ZnS:Mn and PLT thin film for TFEL device was deposited by vacuum evaporation method and RF magnetron sputtering method, respectively. The TFEL device using ZnS:Mn(6000 Å) and PLT(1000 Å) thin films showed the threshold voltage of 50 Vrms at the driving frequency of 3 kHz. The brightness of TFEL device was 250 μW/cm^(2) at the applied voltage of 74 Vrms. Also the output current of TFEL device was linearly increased with applied voltage.

고주파로 스펏터링한 SiO₂막의 제조 및 특성

김영진,박욱동,김기완,오상광,마대영 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

Using RF reactive sputtering method, silicon dioxide(SiO_(2)) thin films have been fabricated on p-type(100) Si wafer. The electrical properties of SiO_(2) thin films have been examined by C-V and I-V measurement. The properties of SiO_(2) thin films on RF power, substrate temperature, O_(2)/Ar+O_(2)ratio and working pressure have been shown differently. The maximum dielectric constant of SiO_(2) thin film was about 2.0 at conditions that the RF power, substrate temperature, O_(2)/Ar+O_(2) and working pressure was 160W, 10%, 250°C and 100mTorr, respectively. This SiO_(2) thin film is expected to be used as the, image sensor blocking layer and TFT gate oxide.

반응성 스펏터링에 의한 TiO₂막의 제조 및 특성

우정옥,박욱동,박기철,김기완 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

The goal of this thesis is to investigate the titanium dioxide (TiO_(2)) thin films for the color sensor application. The TiO_(2) thin films have been fabricated by RF reactive sputtering method. In this time, RF power, substrate temperature, O_(2)/(Ar+O_(2)) ratio and working pressure are 80~220W, 0~300℃, 10~70% and 50~200Torr, respectively. The electrical and optical properties are examined by different deposition conditions. The optical properties of the TiO_(2) thin films deposited on ITO film are examined by optical spectrophotometry in the wavelength range from 300 to 700nm. When RF power, substrate temperature and O_(2)/Ar+O_(2) ratio are 80W, 100℃. 50% and 50mTorr, the values of resistivity and transmittance of the TiO_(2) films in visible region are 5x10^(-3) Ω·cm and about 90s, respectively. The optical bandgap of TiO_(2) films is about 3.6eV.

CdS 광도전막의 제조 및 그 응용

최병진,박욱동,이우일,김기완 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

The Polycrystallized CdS films have been fabricated at the substrate temperature above 200℃ by thermal evaporation method. When the CdS films were annealed at the temperature higher than 400℃, the dark resistivity was increased. From the photoconductive properties of CdS films under 50~1500uW/cm^(2) illumination, the maximum values of I_(p)/I_(d) ratio and photosensitivity were 60dB and 0.82, respectively. The optical properties of CdS films were measured by spectrometer, the optical band gap of CdS film was different with heat treatment, These results show that this evaporated CdS films are expected to be used as photoconductive cells or photoelectric sensors.

반응성 스펏터링법으로 제조한 Ta₂O₅ 막의 특성

금동렬,박욱동,김기완,이우일 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

Tantalum pentoxide(Ta₂O₅) thin films on p-type (100) silicon wafer were fabricated by RF reactive sputtering. Physical properties and structure of the specimens were examined by XRD and AES. From the C-V analysis, the dielectric constant of Ta₂O₅ films was 10-12 in oxygen mixing ratio of 10 %. The ratio of Ta:O was 1:2 and 1:2.49 by AES and RBS examination, respectively. The heat treatment at 700℃ in O₂ ambient led to induce crystallization. When the heat treatment temperature was increased to 1000℃, the dielectric constant was 20.5 in O₂ambient and 23 in N₂ ambient, respectively. This crystal structure was pseudo hexagonal of δ-Ta₂O₅ . The flat band voltage shift(ΔV_(FB)) of the specimens and the leakage current density were decreased with the mixng ratio of oxygen. The maximum breakdown field was 2.4 MV/cm in oxygen mixing ratio of 10 %. These Ta₂O₅ films will be applicable to hydrogen ion sensitive film and gate oxide material of memory device.

Influence of Temperature on Pharmacokinetic Characteristics of Ketoprofen Patch Preparation

Ki Wug Sung 大韓臨床藥理學會 1997 臨床藥理學會誌 Vol.5 No.2

Lamotrigine, an antiepileptic drug, inhibits 5-HT₃ receptor currents in NCB-20 neuroblastoma cells

Ki Jung Kim,Seung Hyun Jeun,Ki-Wug Sung 대한생리학회-대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.2

Lamotrigine is an antiepileptic drug widely used to treat epileptic seizures. Using whole-cell voltage clamp recordings in combination with a fast drug application approach, we investigated the effects of lamotrigine on 5-hydroxytryptamine (5-HT)₃ receptors in NCB-20 neuroblastoma cells. Coapplication of lamotrigine (1~300 μM) resulted in a concentration-dependent reduction in peak amplitude of currents induced by 3 μM of 5-HT for an IC₅₀ value of 28.2±3.6 μM with a Hill coefficient of 1.2±0.1. These peak amplitude decreases were accompanied by the rise slope reduction. In addition, 5-HT₃-mediated currents evoked by 1 mM dopamine, a partial 5-HT₃ receptor agonist, were inhibited by lamotrigine co-application. The EC₅₀ of 5-HT for 5-HT₃ receptor currents were shifted to the right by co-application of lamotrigine without a significant change of maximal effect. Currents activated by 5-HT and lamotrigine co-application in the presence of 1 min pretreatment of lamotrigine were similar to those activated by 5-HT and lamotrigine co-application alone. Moreover, subsequent application of lamotrigine in the presence of 5-HT and 5-hydroxyindole, known to attenuate 5-HT₃ receptor desensitization, inhibited 5-HT₃receptor currents in a concentration-dependent manner. The deactivation of 5-HT₃ receptor was delayed by washing with an external solution containing lamotrigine. Lamotrigine accelerated the desensitization process of 5-HT₃ receptors. There was no voltage-dependency in the inhibitory effects of lamotrigine on the 5-HT₃ receptor currents. These results indicate that lamotrigine inhibits 5-HT₃-activated currents in a competitive manner by binding to the open state of the channels and blocking channel activation or accelerating receptor desensitization.

Characterization of Norepinephrine Release in Rat Posterior Hypothalamus Using<I> in vivo</I> Brain Microdialysis

Ki-Wug Sung,Seong Yun Kim,Ok Nyu Kim,Sang Bok Lee 대한생리학회-대한약리학회 2002 The Korean Journal of Physiology & Pharmacology Vol.6 No.1

<P> In the present study, we used the microdialysis technique combined with high performance liquid chromatography (HPLC) and electrochemical detection to measure the extracellular levels of norepinephrine (NE) in the posterior hypothalamus <I>in vivo</I>, and to examine the effects of various drugs, affecting central noradrenergic transmission, on the extracellular concentration of NE in the posterior hypothalamus. Microdialysis probes were implanted stereotaxically into the posterior hypothalamus (coordinates: posterior 4.3 mm, lateral 0.5 mm, ventral 8 mm, relative to bregma and the brain surface, respectively) of rats, and dialysate collection began 2 hr after the implantation. The baseline level of monoamines in the dialysates were determined to be: NE 0.17⁑0.01, 3,4-dihydroxyphenylacetic acid (DOPAC) 0.94⁑0.07, homovanillic acid (HVA) 0.57⁑0.05 pmol/sample (n=8). When the posterior hypothalamus was perfused with 90 mM potassium, maximum 555% increase of NE output was observed. Concomitantly, this treatment significantly decreased the output of DOPAC and HVA by 35% and 28%, respectively. Local application of imipramine (50μM) enhanced the level of NE in the posterior hypothalamus (maximum 200%) compared to preperfusion control values. But, DOPAC and HVA outputs remained unchanged. Pargyline, an irreversible monoamine oxidase inhibitor, i.p. administered at a dose of 75 mg/kg, increased NE output (maximum 165%), while decreased DOPAC and HVA outputs (maximum 13 and 12%, respectively). These results indicate that NE in dialysate from the rat posterior hypothalamus were neuronal origin, and that manipulations which profoundly affected the levels of extracellular neurotransmitter had also effects on metabolite levels.