• 제목/요약/키워드: $BiNbO_4$

Search Result 108, Processing Time 0.094 seconds

Electrical Properties of SrBi$_2$$Nb_2$>$O_9$ Thin Films deposited by RF Magnetron Sputtering Method (RF 마그네트론 스퍼터링법에 의해 증착된 SrBi$_2$$Nb_2$>$O_9$ 박막의 전기적 특성에 관한 연구)

  • Zhao, Jin-Shi;Choi, Hoon-Sang;Lee, Kwan;Choi, In-Hoon
    • Korean Journal of Materials Research
    • /
    • v.11 no.4
    • /
    • pp.290-293
    • /
    • 2001
  • The SrBi$_2$Nb$_2$O$_{9}$ (SBN) thin films were deposited on p-type(100) Si substrates by rf magnetron sputtering to confirm the Possibility of Pt/SBN/Si structure for the application of nondestructive read out ferroelectric random access memory (NDRO- FRAM). The SBN thin films were deposited by co-sputtering method with Sr$_2$Nb$_2$O$_{7}$ (SNO) and Bi$_2$O$_3$ ceramic targets. The SBN thin films deposited at room temperature were annealed at $700^{\circ}C$ for 1hr in $O_2$ ambient. The structural and electrical properties of SBN with different power ratios of targets were measured by x-ray diffraction(XRD), scanning electron microscopy(SEM), capacitance-voltage(C-V), and current-voltage(I-V). The C-V curves of the SBN films showed hysteresis curves of a clockwise rotation showing ferroelectricity. When the Power ratio of the SNO/Bi$_2$O$_3$ targets was 120 W/100 W, the SBN thin films had excellent electrical properties. The memory window of SBN thin film was 1.8 V-6.3 V at applied voltage of 3 V-9 V and the leakage current density was 1.5 $\times$ 10$^{-7}$ A/$\textrm{cm}^2$ at applied voltage of 5 V The composition of SBN thin films was analysed by electron probe X-ray micro analyzer(EPMA) and the atomic ratio of Sr:Bi:Nb with pawer ratio of 120 W/100 W was 1:3:2.

  • PDF

Structural and Electrical Properties of $(Na_{0.5}K_{0.5})NbO_3$ ceramics addition with $BiTiO_3$ (BiTiO3 첨가에 따른 (Na0.5K0.5)NbO3 세라믹스의 구조적 전기적 특성)

  • Lee, Tae-Ho;Kim, Dae-Young;Jo, Seo-Hyeon;Jeong, Gwang-Ho;Lee, Sung-Gap;Nam, Sung-Pill;Kim, Young-Gon
    • Proceedings of the KIEE Conference
    • /
    • 2011.07a
    • /
    • pp.1465-1466
    • /
    • 2011
  • We have studied structural and electrical properties of $(Na_{0.5}K_{0.5})NbO_3$ ceramics addition with $BiTiO_3$. The $(Na_{0.5}K_{0.5})NbO_3-BiTiO_3$ ceramics were fabricated by the conventional mixed oxide method, their dielectric and piezoelectric properties were investigated with the variations of additvie amount $BiTiO_3$. At the sintering temperature of $1130^{\circ}C$, the density, dielectric constant, grain size of 0.05mol% $BiTiO_3$ specimen showed the values of 4.69 g/$cm^3$, 898 and $24.8{\mu}m$.

  • PDF

Low-Voltage, Room temperature Fabricated ZnO Thin Film Transistor using High-K $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ Gate Insulator (고유전 $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ 게이트 절연막을 이용한 저전압 구동 상온공정 ZnO 박막트랜지스터)

  • Cho, Nam-Gyu;Kim, Dong-Hun;Kim, Kyoung-Sun;Kim, Ho-Gi;Kim, Il-Doo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.11a
    • /
    • pp.96-96
    • /
    • 2007
  • Low voltage organic TFTs (OTFTs) and ZnO based TFTs (<5V), utilizing room temperature deposited $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ (BZN) thin films were recently reported, pointing to high-k gate insulators as a promising route for realizing low voltage operating flexible electronics. $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ (BZN) thin film is one of the most promising materials for gate insulator because of its large dielectric constant (~60) at room temperature. However their tendency to suffer from relatively high leakage current at low electric field (>0.3MV/cm) hinder the application of BZN thin films for gate insulator. In order to improve leakage current characteristics of BZN thin film, we mixed 30mol% MgO with 70mol% BZN and their dielectric and electric properties were characterized. We fabricated field-effect transistors with transparent oxide semiconductor ZnO serving as the electron channel and high-k $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ as the gate insulator. The devices exhibited low operation voltages (<4V) due to high capacitance of the $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ dielectric.

  • PDF

Effect of CdO addition on the microwave dielectric properties of BiNbO$_4$ceramics using mobile communication (이동통신용 BiNbO$_4$세라믹스의 CdO 첨가량에 따른 고주파 유전 특성)

  • 윤중락;이헌용
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1997.11a
    • /
    • pp.405-408
    • /
    • 1997
  • The microwave dielectric properties of CuO and CdO addition of BiNbO$_4$ceramics were investigated. As the content of CdO increased, sintered density and quality factor is decreased. With increase in sintering temperature, the dielectric constant and quality factor is increased. In case of specimen sintered at 96$0^{\circ}C$ with 0.03 wt% CuO and CdO, the microwave dielectric properties obtained were dielectric constant of 41.2, quality factor (Q$\times$f) of 6, 500, temperature coefficient of resonant frequency of ppm/$^{\circ}C$.

  • PDF

Effect of CuO Addition on the Microwave Dielectric Properties of $BiNbO_4$ Ceramics (CuO의 첨가가 $BiNbO_4$ 세라믹스의 마이크로파 유전특성에 미치는 영향)

  • Mun, Myeong-Rip;Bae, Gyu-Sik;Kim, Wang-Seop;Kim, Gyeong-Yong
    • Korean Journal of Materials Research
    • /
    • v.6 no.12
    • /
    • pp.1186-1191
    • /
    • 1996
  • CuO의 첨가가 BiNbO4 세라믹스의 마이크로파 유전특성과 소결거동에 미치는 영향에 대하여 연구하였다. CuO의 첨가량이 증가함에 따라 액상의 생성에 의해 소결성이 증가하여 시편의 밀도는 증가하며 유전상수는 소결온도가 증가함에 따라 증가하는 경향을 보였다. Qxfo값은 CuO 첨가량이 0.065wt%이고 소결온도가 94$0^{\circ}C$일 때 최대값을 나타내며 그 이상 CuO 첨가량을 증가하였다. 소결온도 92$0^{\circ}C$-96$0^{\circ}C$, 소결시간 2시간일 때의 고주파 유전특성으로는 유전상수가 43.6, Qxfo값이 13,200 이상, $\tau$f =-14.36ppm/$^{\circ}C$을 얻었다.

  • PDF

Effects of Nb2O5 and MnO2 on the PTCR behavior of Lead-free Ba0.99(Bi1/2Na1/2)0.01TiO3 Ceramics (무연 Ba0.99(Bi1/2Na1/2)0.01TiO3 세라믹의 PTCR 특성에 미치는 Nb2O5와 MnO2의 효과)

  • Park, Yong-Jun;Nahm, Sahn;Lee, Young-Jin;Jeong, Young-Hun;Paik, Jong-Hoo;Kim, Dae-Joon;Lee, Woo-Young
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.21 no.7
    • /
    • pp.638-644
    • /
    • 2008
  • The effects of $Nb_2O_5$ and $MnO_2$ on the positive temperature coefficient of resistivity (PTCR) behavior of lead-free $Ba_{0.99}(Bi_{1/2}Na_{1/2})_{0.01}TiO_3$ (BaBiNT) ceramics were investigated in order to fabricate a PTC thermistor available at high temperature of > $120^{\circ}C$. In particular, 0.05 mol% $Nb_2O_5$ added BaBiNT ceramic, which has significantly increased Curie temperature (Tc) of $160^{\circ}C$, showed good PTCR behavior; low resistivity at room temperature $(\rho_r)$ of $80.1{\Omega}{\cdot}cm$, a high $\rho_{max}/\rho_{min}$ ratio of $5.65{\times}10^3$ and a large resistivity temperature factor (a) of 18.5%/$^{\circ}C$. Furthermore, the improved $\rho_{max}/\rho_{min}$ of $6.48{\times}10^4$ and a of 25.4%/$^{\circ}C$ along with higher $T_c$ of $167^{\circ}C$ despite slightly increased $\rho_r$ of $569{\Omega}{\cdot}cm$, could be obtained for the BaBiNT + 0.05 mol% $Nb_2O_5$ + 0.02 wt% $MnO_2$ ceramic cooled down at a rate of $200^{\circ}C/h$.

Microwave Dielectric Properties of Ca[($Li_{1/3}Nb_{2/3}$)$_{1-x}$$Ti_{x}$]$O_{3-{\delta}}$ with $Bi_2O_3$ Additives ($Bi_2O_3$ 첨가에 의한 Ca[($Li_{1/3}Nb_{2/3}$)$_{1-x}$$Ti_{x}$$O_{3-{\delta}}$ 세라믹스의 마이크로파 유전 특성)

  • 하종윤;최지원;이동윤;윤석진;최두진;김현재
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.07a
    • /
    • pp.131-134
    • /
    • 2002
  • The effect of the addition on the densification, low temperature sintering, and microwave dielectric properties of the Ca[($Li_{1/3}Nb_{2/3}$)$_{1-x}$$Ti_{x}$]$O_{3-{\delta}}$/(CLNT) was investigated. $Bi_2O_3$ additives improved the dencification and reduced the sintering temperature from $1150^{\circ}C$ to $900^{\circ}C$ of CLNT microwave dielectric ceramics. As increasing $Bi_2O_3$ contents, the dielectric constants and bulk density were increased. The quality factor, however, was decreased slighty. The temperature coefficients of the resonant frequency shifted positive value as increasing $Bi_2O_3$ contents. The dielectric properties of Ca[($Li_{1/3}Nb_{2/3}$)$_{1-x}$$Ti_{x}$]$O_{3-{\delta}}$ and Ca[($Li_{1/3}Nb_{2/3}$)$_{0.8}Ti_{0.2}$]$O_{3-{\delta}}$ with 5wt% $Bi_2O_3$ sintered at $900^{\circ}C$ for 3h were $\varepsilon_{r}$=20, 35 Q.$f_{0}$=6500, 11,000 GHz, $\tau_{f}$=4, 13 ppm/$^{\circ}C$, respectively.

  • PDF

Structural and Electrical Properties of (Na0.465K0.465Bi0.07)(Nb0.93Ti0.07)O3-0.08MnO2 Ceramics with Variation of Sintering Temperature (소결온도에 따른 (Na0.465K0.465Bi0.07)(Nb0.93Ti0.07)O3-0.08MnO2 세라믹스의 구조적, 전기적 특성)

  • Lee, Tae-Ho;Yeo, Jin-Ho;Lee, Sung-Gap
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.25 no.7
    • /
    • pp.506-510
    • /
    • 2012
  • In this study, lead-free $(Na_{0.465}K_{0.465}Bi_{0.07})(Nb_{0.93}Ti_{0.07})O_3-0.08MnO_2$ ceramics were fabricated by conventional mixed oxide method. Structural and electrical properties of lead-free $(Na_{0.465}K_{0.465}Bi_{0.07})(Nb_{0.93}Ti_{0.07})O_3-0.08MnO_2$ ceramics with the variation of sintering temperature were investigated. As results of x-ray diffraction analysis, all specimens showed a typical polycrystalline perovskite structure without presence of the second phase. Sintered density increased with an increases of sintering temperature and the specimen sintered at $1,020^{\circ}C$ showed the maximum value of 4.5 $g/cm^3$. The average grain size of the $(Na_{0.465}K_{0.465}Bi_{0.07})(Nb_{0.93}Ti_{0.07})O_3-0.08MnO_2$ specimen sintered at $1,020^{\circ}C$ is about 0.83 ${\mu}m$. Electromechanical coupling factor, relative dielectric constant and dielectric loss of $(Na_{0.465}K_{0.465}Bi_{0.07})(Nb_{0.93}Ti_{0.07})O_3-0.08MnO_2$ specimens sintered at $1,020^{\circ}C$ were 0.252, 741 and 0.043% respectively.

Ferroelectric properties of SBN-BTN ceramics with variation of the ball-milling time (볼-밀 시간에 따른 SBN-BTN 세라믹의 강유전 특성)

  • Lee, Won-Sub;Lee, Sung-Gap;Bae, Seon-Gi
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.07b
    • /
    • pp.549-552
    • /
    • 2002
  • $(SrBi_2Nb_2O_9)_{0.5}-(Bi_3TiNbO_9)_{0.5}$ ceramics were fabricated by the mixed-oxide method, and the structural and electrical properties with variation of ball-milling time were investigated. All SBN-BTN specimens showed the typical polycrystalline X-ray diffraction patterns without the presence of the second phase. The SBN-BTN specimen sintered at $1200^{\circ}C$ and ball-milled for 168h showed the average grain size of $16{\mu}m$. The dielectric constant and dielectric loss of the SBN-BTN specimen sintered at $1150^{\circ}C$ and ball-mill for 72h were 225, 0.4% at 1KHz, respectively.

  • PDF