• 제목/요약/키워드: Ion Channel

검색결과 445건 처리시간 0.027초

Twin-well 구조로 제작된 N채널 및 P채널 FET의 특성 (Characteristics of N-and P-Channel FETs Fabricated with Twin-Well Structure)

  • 김동석;이철인;서용진;김태형;김창일;장의구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1992년도 춘계학술대회 논문집
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    • pp.86-90
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    • 1992
  • We have studied the characteristics of n-and p-channel FETs with submicron channel length fabricated by twin-well process. Threshold voltage variation and potential distribution with channel ion implantation conditions and impurity profile of n-and p-channel region wee simulated using SUPREM-II and MINIMOS 4.0 simulater, P-channel FET had buried-channel in the depth of 0.15 $\mu\textrm{m}$ from surface by counter-doped boron ion implantation for threshold voltage adjustment. As a result of device measurement, we have obtained good drain saturation characteristics for 3.3 [V] opreation, minimized short channel effect with threshold voltage shift below 0.2[V], high punchthrough and breakdown voltage above 10[V] and low subthreshold value.

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$K^{+}$$Ag^{+}$ 이온교환 도파로의 광결합 특성 (The optical coupling characteristics of $K^{+}$ and $Ag^{+}$ ion-exchanged waveguide)

  • 김홍석;이병석;천석표;이현용;정흥배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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    • pp.284-287
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    • 1996
  • In this paper, we investigated the optical coupling characteristics for $K^{+}$ ion-exchanged diffused channel waveguide by using coupled-mode equations. In this case, the optical-power-dividing was observed at the waveguide-type optical coupler with 3[$\mu\textrm{m}$] line-width and, 6[$\mu\textrm{m}$] separation between channel waveguides in which interaction lengths were 1 and 3[mm], respectively, On the basis of that we deformed simulation for $Ag^{+}$ ion-exchanged diffused channel waveguide. As a result of simulation, the optical-power-dividing was shown at the waveguide-type optical coupler wish 3[$\mu\textrm{m}$] line-width, 6[$\mu\textrm{m}$] separation between channel waveguides and 0.11[mm] interaction length.

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A Two-Dimensional (2D) Analytical Model for the Potential Distribution and Threshold Voltage of Short-Channel Ion-Implanted GaAs MESFETs under Dark and Illuminated Conditions

  • Tripathi, Shweta;Jit, S.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제11권1호
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    • pp.40-50
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    • 2011
  • A two-dimensional (2D) analytical model for the potential distribution and threshold voltage of short-channel ion-implanted GaAs MESFETs operating in the sub-threshold regime has been presented. A double-integrable Gaussian-like function has been assumed as the doping distribution profile in the vertical direction of the channel. The Schottky gate has been assumed to be semi-transparent through which optical radiation is coupled into the device. The 2D potential distribution in the channel of the short-channel device has been obtained by solving the 2D Poisson's equation by using suitable boundary conditions. The effects of excess carrier generation due to the incident optical radiation in channel region have been included in the Poisson's equation to study the optical effects on the device. The potential function has been utilized to model the threshold voltage of the device under dark and illuminated conditions. The proposed model has been verified by comparing the theoretically predicted results with simulated data obtained by using the commercially available $ATLAS^{TM}$ 2D device simulator.

Transient Receptor Potential Ion Channels and Animal Sensation: Lessons from Drosophila Functional Research

  • Kim, Chang-Soo
    • BMB Reports
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    • 제37권1호
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    • pp.114-121
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    • 2004
  • Ion channels of the transient receptor potential (TRP) superfamily are non-selective cationic channels with six transmembrane domains. The TRP channel made its first debut as a light-gated $Ca^{2+}$ channel in Drosophila. Recently, research on animal sensation in Drosophila disclosed other members of the TRP family that are required for touch sensation and hearing as well as the sensation of painful stimuli.

Effects of t-Butyl Hydrogen Peroxide on the Maxi-K Channels of Rat Brain

  • Shin, Jung-Hoon;Suh, Chang-Kook
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1998년도 학술발표회
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    • pp.33-33
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    • 1998
  • Oxidation and reduction of amino acid residues in proteins affect their functional properties. Especially, redox modulation of ion channel activities has been reported in number of ion channel proteins. In this study, we investigated the effects of tertiary-butyl hydrogen peroxide (tBHP) on the large-conductance Ca$\^$2+/ -activated K$\^$+/(Maxi-K) channel of rat brain using lipid bilayer reconstitution technique.(omitted)

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$BF_2$ 이온 주입한 표면 채널 LDD PMOSFET의 Hot-Carrier 효과 (Hot-Carrier Effects of $BF_2$ Ion-Implanted Surface-Channel LDD PMOSFET)

  • 양광선;박훈수;김봉렬
    • 전자공학회논문지A
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    • 제28A권12호
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    • pp.53-58
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    • 1991
  • Hot-carrier induced degradation has been studied for the BF$_2$ ion-implanted surface-channel LDD(P$^{+}$ polysilicon gate) PMOSFET in comparison to the buried-channel structure(N$^{+}$ polysilicon gate) PMOSFET. The conditions for maximum degradation better correlated to I$_{g}$ than I$_{sub}$ for both PMOSFET's. Due to the use of LDD structure on SC-PMOSFET, the substrate current for SC-PMOSFET was shown to be smaller than that of BC-PMOSFET. The gate current was smaller as well, due to the gate material work-function difference between p$^{+}$ and n$^{+}$ polysilicon gates. From the results, it was shown that the surface-channel LDD PMOSFET is more resistant to short channel effect than the buried-channel PMOSFET.

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매몰채널 pMOSFET소자의 서브쓰레쉬홀드 특성 고찰 (Subthreshold characteristics of buried-channel pMOSFET device)

  • 서용진;장의구
    • E2M - 전기 전자와 첨단 소재
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    • 제8권6호
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    • pp.708-714
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    • 1995
  • We have discussed the buried-channel(BC) behavior through the subthreshold characteristics of submicron PMOSFET device fabricated with twin well CMOS process. In this paper, we have guessed the initial conditions of ion implantation using process simulation, obtained the subthreshold characteristics as a function of process parameter variation such as threshold adjusting ion implant dose($D_c$), channel length(L), gate oxide thickness($T_ox$) and junction depth of source/drain($X_j$) using device simulation. The buried channel behavior with these process prarameter variation were showed apparent difference. Also, the fabricated pMOSFET device having different channel length represented good S.S value and low leakage current with increasing drain voltage.

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In Silico Study of the Ion Channel Formed by Tolaasin I Produced by Pseudomonas tolaasii

  • Jo, Geun-Hyeong;Hwang, Do-Seok;Lee, Sun-Hee;Woo, Yoon-Kyung;Hyun, Ji-Ye;Yong, Yeon-Joong;Kang, Kyung-Rai;Kim, Dong-Woon;Lim, Yoong-Ho
    • Journal of Microbiology and Biotechnology
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    • 제21권10호
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    • pp.1097-1100
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    • 2011
  • A toxin produced by Pseudomonas tolaasii, tolaasin, causes brown blotch disease in mushrooms. Tolaasin forms pores on the cellular membrane and destroys cell structure. Inhibiting the ability of tolaasin to form ion channels may be an effective method to protect against attack by tolaasin. However, it is first necessary to elucidate the three-dimensional structure of the ion channels formed by tolaasin. In this study, the structure of the tolaasin ion channel was determined in silico based on data obtained from nuclear magnetic resonance experiments.

[ $Ce^{4+}$ ]-Stimulated Ion Fluxes Are Responsible for Apoptosis and Taxol Biosynthesis in Suspension Cultures of Taxus Cells

  • Li Jing-Chuan;Ge Zhi-Qiang;Yuan Ying-Jin
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제10권2호
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    • pp.109-114
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    • 2005
  • Ion fluxes across the plasma membrane activated by 1 mM $Ce^{4+}$, cell apoptosis and taxol biosynthesis in suspension cultures of Taxus cusp/data were studied. The extracellular pH sharply decreased upon the addition of 1 mM $Ce^{4+}$, then increased gradually and exceeded the initial pH value over a time period of 12 h. The extracellular $Ca^{2+}$ concentration decreased within the first 3 h after the addition of $Ce^{4+}$, then gradually decreased to one third of initial value in control at about 72 h and remained unchanged afterwards. Experiments with an ion channel blocker and a $Ca^{2+}$-channel blocker indicated that the dynamic changes in extracellular pH and the $Ca^{2+}$ concentration resulted from the $Ce^{4+}$-induced activation of W uptake and $Ca^{2+}$ influx across the plasma membrane via ion channels. A pretreatment of the ion channel blocker initiated $Ce^{4+}$-treated cells to undergo necrosis, and the prior addition of the $Ca^{2+}$-channel blocker inhibited $Ce^{4+}$-induced taxol biosynthesis and apoptosis. It is thus inferred that W uptake is necessary for cells to survive a $Ce^{4+}$-caused acidic environment and is one of the mechanisms of $Ce^{4+}$-induced apoptosis. Furthermore, the $Ca^{2+}$ influx across the plasma membrane mediated both the $Ce^{4+}$-induced apoptosis and taxol biosynthesis.