• 제목/요약/키워드: (Sr0.85Ca0.15)TiO3

검색결과 17건 처리시간 0.023초

알칼리 금속 이온의 입계확산에 따른 $(SrCa)TiO_3$ 소결체의 입계구조 및 전기적 특성 (Grain boundary structure and electrical characteristics of alkaline metallic cation-diffused $(SrCa)TiO_3$ ceramics)

  • 허현;조남희
    • 한국군사과학기술학회지
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    • 제2권1호
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    • pp.183-193
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    • 1999
  • 환원분위기 소결조건에서 반도성 (Sr0.85Ca0.15)TiO3 소결체를 제조한후, 금속 양이온(Na, K)을 소결체 입계를 통해 확산시켜 확산시간과 확산량에 따른 소결체의 전기적 특성 변화를 고찰하였다. K이온과 Na 이온을 입계확산시킨 경우 반도성 소결체는 바리스터 특성을 나타내며, 확산시간과 확산량이 증가함에 따라 문턱전압이 증가하였다. 이들 소결체의 입계전위장벽은 0.01 ~ 2.89 eV이며 입계저항은 2.2 ~ 120.4 $M{\Omega}$ 값을 나타냈다 투과전자현미경을 이용하여 입계의 구조를 관측하였으며 이들 결과와 소결체의 전기적 특성과의 상관관계를 고찰하였다.

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RF 스퍼터링법에 의한 $(Sr_{0.85}Ca_{0.15})TiO_3$ 박막의 전압-전류 특성 (V-I Characteristics of $(Sr_{0.85}Ca_{0.15})TiO_3$ Thin Film by RF Sputtering Method)

  • 김진사;조춘남;신철기;최운식;김충혁;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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    • pp.88-91
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    • 2000
  • The $(Sr_{0.85}Ca_{0.15})TiO_3$(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/$SiO_2$/Si) using RF sputtering method. The crystallinity of SCT thin films is increased with increase of substrate temperature in the temperature range of 200~500$[^{\circ}C]$. V-I characteristics of SCT thin films show the increasing leakage current with the increases of deposition temperature. The conduction mechanism of the SCT thin films observed in the temperature range of 25~100$[^{\circ}C]$ can be divided into four characteristic regions with different mechanism by the increasing current.

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열처리온도에 따른 $(Sr_{0.85}Ca_{0.15})TiO_3$박막의 구조 및 특성 (Microstructure and Properties of $(Sr_{0.85}Ca_{0.15})TiO_3$ Thin Film with Annealing Temperature)

  • 김진사;조춘남;신철기;최운식;김충혁;이준웅
    • 한국전기전자재료학회논문지
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    • 제14권10호
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    • pp.802-807
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    • 2001
  • The (S $r_{0.85}$C $a_{0.15}$)Ti $O_{3}$(SCT) thin films are deposited on Pt-coated electrode (Pt/TiN/ $SiO_2$/Si) using RF sputtering method. The composition of SCT thin films deposited on Si substrate at woom temperature is close to stoichiometry(1.102 in A/B ratio). The maximum dielectric constant of SCT thin films is obtained by annealing at 600[$^{\circ}C$]. The capacitance characteristics had a stable value within $\pm$4[%]. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films is observed above 200[kHz]. SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequencey.cey.

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RF 스퍼터링법에 의한 ($Sr_{0.85}Ca_{0.15})TiO_3$ 박막의 전기적 특성 (Electrical Characteristics of ($Sr_{0.85}Ca_{0.15})TiO_3$ Thin Film by RF Sputtering Method)

  • 장원석;김진사;최운식;김충혁;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
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    • pp.239-242
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    • 1998
  • The (S $r_{0.85}$C $a_{0.15}$)Ti $O_3$ (SCT) thin films are deposited on Pt-coated electrode using RF magnetron sputtering method at various substrate temperature. Dielectric constant of SCT thin films is increased with increased as the deposition temperature and changes almost linearly in temperature ranges from -80 to +90[$^{\circ}C$]. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films is observed above 200[kHz]. V-I characteristics of SCT thin films show the increasing leakage current with the increases of deposition temperature.ure.

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RF 스퍼터링법에 의한 (SrCa)Ti $O_3$ 세라믹 박막의 제초 및 미세구조 (Fabrication and microstructure of (Sr .Ca)Ti $O_3$ Ceramic Thin Films by RF Sputtering Method-)

  • 김진사;정일형;백봉현;김충혁;최운식;오재한;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.189-193
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    • 1997
  • (S $r_{0.85}$/C $a_{0.15}$)Ti $O_3$(SCT) thin films at various deposition temperature and rf power were grown by rf magnetron sputtering method on optimized Pt-based electrodes (Pt/TiN/ $SiO_2$/Si). The crystallinity of the films increases with increasing deposition temperature. SCT thin film is depend on the surface morphology and crystallinity of Pt films for bottom electrode. Dielectric constant of (S $r_{0.85}$C $a_{0.15}$)Ti $O_3$ thin films deposited on Si wafer substrate are larger with the increase of deposition temperature and gain size.in size.

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$(Sr_{0.85}{\cdot}Ca_{0.15})_mTiO_3$ 입계층 세라믹의 하전입자 거동 (Behavior of Charged Particles do $(Sr_{0.85}{\cdot}Ca_{0.15})_mTiO_3$ Grain Boundary Layer Ceramics)

  • 김진사;정동효;김상남;박재세;최운식;이준용
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.209-212
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    • 1995
  • In this paper, the $(Sr_{0.85}{\cdot}Ca_{0.15})TiO_3$ of paraelectric grain boundary layer (GBL) ceramics were fabricated. The characteristics of electrical conduction and the thermally stimulated current(TSC) were measured respectively. The region I below 200[V/cm] shows the ohmic conduction, the region II between 200[V/cm] and 1000[V/cm] can be explained by the Pool-Frenkel emission theory, and the region III above 2000[V/cm] is dominated by the tunneling effect. As a result, The origins of these peaks are that the ${\alpha}$ peak observed at $-20[^{\circ}C]$ looks like to be ascribed to the ionization excitation from donor level in the grain, and the ${\alpha}^{\prime}$ peak observed at $-20[^{\circ}C]$ appears to show up by detrap of the trapped carrier of border between the oxidation layer and the grain, and the ${\beta}$ peak observed at $80[^{\circ}C]$ seems to be resulted from hopping conduction of existing carrier in the trap site of the border between the oxidation and second phase.

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상부전극에 따른 $(Sr_{0.85}Ca_{0.15})TiO_3$ 박막의 전기적 특성 (Electrical Properties of $(Sr_{0.85}Ca_{0.15})TiO_3$ Thin Films with Top Electrodes)

  • 조춘남;김진사;신철기;오재한;최운식;김충혁;이준웅
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권2호
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    • pp.107-112
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    • 2000
  • $(Sr_{0.85}Ca_{0.15})TiO_3$(SCT) thin films were deposited on Pt-coated $TiO_2/SiO_2/Si$ wafer by the rf sputtering method. Experiments were conducted to investigate the electrical properties of SCT thin films with various top electrodes. Various top electrodes as Pt, Al, Ag, Cu were deposited on SCT thin films by sputter and thermal evaporator. The characteristics of C-F and C-V of SCT thin films were not obviously varied with various top electrodes, SCT thin films annealed at $600^{\circ}C$ represents as favorable capacitance characteristics than SCT thin films not annealed, and Pt top electrode have the most high capacitance. The characteristic of I-V of SCT thin films showed that Pt top electrode revealed more less leakage current density than other electrodes, had a leakage current density below 10-8$[A/cm^2]$ until 25[V] applied voltage.

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$(Sr_{0.85}-Ca_{0.15})$$TiO_3$ 입계층 세라믹의 열자력전류 특성에 관한 연구 (A study on the properties of thermally stimulated current of $(Sr_{0.85}-Ca_{0.15})$$TiO_3$ grain boundary layer ceramic)

  • 김진사;김성열;유영각;최운식;이준웅
    • E2M - 전기 전자와 첨단 소재
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    • 제9권4호
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    • pp.396-403
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    • 1996
  • In this paper, the (S $r_{0.85}$.C $a_{0.15}$)Ti $O_{3}$ of paraelectric grain boundary layer (GBL) ceramics were fabricated, and the analysis of microstructuye and the thermally stimulated current(TSC) were investigated for understanding effects of GBL's interfacial phenomenon on variations of electrical properties. As a result, the three peaks of .alpha., .alpha. and .betha. were obtained at the temperature of -20 [.deg. C], 20[.deg. C] and 80[.deg. C], respectively. The origins of these peaks are that the .alpha. peak observed at -20[.deg. C] looks like to be ascribed to the ionization excitation from donor level in the grain, and the .alpha.' peak observed at 20[.deg. C] appears to show up by detrap of the trapped carrier of border between the oxidation layer and the grain, and the .betha. peak observed at 80[.deg. C] seems to be resulted from hopping conduction of existing carrier in the trap site of the border between the oxidation and second phase. and second phase.

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($Sr_{1-x}Ca_x)TiO_3$ 세라믹 박막의 제조 및 유전특성 (Fabrication and Dielectric Properties of $(Sr_{1-x}Ca_x)TiO_3$ Ceramic Thin Films)

  • 김진사;조춘남;오용철;신철기;김충혁;송민종;소병문;최운식;이준웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1496-1498
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    • 2003
  • The $(Sr_{0.85}Ca_{0.15})TiO_3$(SCT) thin films were deposited on Pt-coated electrode (Pt/TiN/$SiO_2$/Si) using RF sputtering method according to the deposition condition. The optimum conditions of RF power and Ar/$O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin films was about 18.75[${\AA}/min$] at the optimum condition. The capacitance characteristics had a stable value within ${\pm}4[%]$. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films were observed above 200[kHz].

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SCT 세라믹 박막의 제조 및 구조적 특성 (Fabrication and Structural Properties of SCT Ceramic Thin Film)

  • 김진사;조춘남;송민종;소병문;최운식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.1084-1087
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    • 2001
  • The (Sr$\sub$0.85/Ca$\sub$0.15/)TiO$_3$(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/SiO$_2$/Si) using RF sputtering method. The crystallinity of SCT thin films is increased with increase of substrate temperature in the temperature range of 100[$^{\circ}C$]∼500[$^{\circ}C$]. Also, the crystallinity of SCT thin films are obtained at the substrate temperature above 400[$^{\circ}C$]. SCT thin films had (111) preferred orientation. The dielectric constant changes almost linearly in temperature ranges of-80∼+90[$^{\circ}C$]. The temperature properties of the dielectric loss have a stable value within 0.1. SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].

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