• 한국전기전자재료학회논문지
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• 제20권4호
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• pp.342-347
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• 2007

$Bi_6Mg_2Nb_4O_{21}(BMN)$ thin films were deposited at various substrates by sputtering system for embedded capacitor applications. BMN thin films deposited at room temperature are manufactured as MIM(Metal/Insulator/Metal) structures. Dielectric properties and leakage current density were investigated as a function of various substrates and thickness of BMN thin films. Leakage current density of BMN thin films deposited on CCL(Copper Clad Laminates) showed relatively high value ($1{\times}10^{-3}A/cm^2$) at an applied field of 300 kV/cm on substrates, possibly due to relatively high value of roughness(rms $50{\AA}$) of CCL substrates. 100 nm-thick BMN thin films deposited on Cu/Ti/Si substrates showed the capacitance density of $300 nF/cm^2$, a dielectric constant of 32, a dielectric loss of 2 % at 100 kHz and the leakage current density of $1{\times}10^{-6}A/cm^2$ at an applied field of 300 kV/cm. BMN capacitors are expected to be promising candidates as embedded capacitors for printed circuit board(PCB).

• 한국세라믹학회지
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• 제25권6호
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• pp.639-644
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• 1988

The physical and dielectric properties of complex perovskite compound Sr(Mg1/3Nb1/3)O3-Ba(Mg1/3Nb2/3)O3-Ba(Mg1/3Ta2/3)O3(BMT) system were investigated as a function of composition. As the mole ratio of BMN was increased, lattice parameter ratio c/a was slightly increased, and density was increased in SMN-BMN system. However, in BMN-BMT system, lattice parameter ratio c/a and density were decreased with increasing the mole ratio of BMN. Dielectric constant, dielectric loss at $25^{\circ}C$ and 100kHz, and temperature coefficient of resonant frequency, the dependence of temperature in capacitance were increased with increasing the mole ratio of BMN in SMN-BMN-BMT system. These result can be explained according to the degree of order=disorder and dielectric constant.

• 터널과지하공간
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• 제29권6호
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• pp.367-378
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• 2019

IT기술의 발전에 따라 무선 네트워크 통신을 사용하여 실시간으로 지하공사 현장을 관리하는 방안이 고려되고 있다. 지하공간은 밀폐된 통신환경과 공간적인 특성으로 인해 지상에 비해 상대적으로 사용에 제한이 있다. BMN(Bluetooth Mesh Networking) 기술은 최근에 소개된 무선통신 기술로 중계기 역할을 하는 블루투스 장비로 네트워크 망을 형성하고 개별 기기를 모니터링하는 기술이다. 본 기술기사에서는 BMN 기술의 지하공간 적용성을 분석하기 위해 고려해야 할 부분과 현재 국내외에서 개발되고 있는 무선통신 모니터링 시스템 사례 및 연구에 대해 조사하였다. 그리고 지하공간 적용을 목표로 개발이 진행되고 있는 국내 BMN 기술에 대해서도 소개하고 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.45-45
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• 2007

Capacitors among the embedded passive components are most widely studied because they are the major components in terms of size and number and hard to embed compared with resistors and inductors due to the more complicated structure. To fabricate a capacitor-embedded PCB for in-line process, it is essential to adopt a low temperature process (<$200^{\circ}C$). However, high dielectric materials such as ferroelectrics show a low permittivity and a high dielectric loss when they are processed at low temperatures. To solve these contradicting problems, we studied BMN materials as a candidate for dielectric capacitors. processed at PCB-compatible temperatures. The morphologies of BMN thin films were investigated by AFM and SEM equipment. The electric properties (C-F, I-V) of Pt/BMN/Cu/polymer were evaluated using an impedance analysis (HP 4194A) and semiconductor parameter analyzer (HP4156A). $Bi_2Mg_{2/3}Nb_{4/3}O_7$(BMN) thin films deposited on copper clad laminate substrates by sputtering system as a function of Ar/$O_2$ flow rate at room temperature showed smooth surface morphologies having root mean square roughness of approximately 5.0 nm. 200-nm-thick films deposited at RT exhibit a dielectric constant of 40, a capacitance density of approximately $150\;nF/cm^2$, and breakdown voltage above 6 V. The crystallinity of the BMN thin films was studied by TEM and XRD. BMN thin film capacitors are expected to be promising candidates as embedded capacitors for printed circuit board (PCB).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.208-211
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• 2000

Ba(Mg$_{1}$3/$Nb_{2/3}$)O$_3$ powders were synthesised from mechanochemically treated mixtures of Ba(OH)$_2$. 8$H_2O$, MgO and Nb$_2$O$_{5}$. Perovskite BMN powder of nanosized particles was successfully synthesized by using mechanochemical methods. Density and dielectric constant of samples with mechanochemical methods showed higher values than those of conventional processing.ng.

• Transactions on Electrical and Electronic Materials
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• 제8권4호
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• pp.153-156
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• 2007

Structural and electrical properties of the fully crystallized-bismuth magnesium niobate ($Bi_2Mg_{2/3}Nb_{4/3}O_7$, BMN) films with 15 mol% excess bismuth deposited on Pt bottom electrode by pulsed laser deposition are characterized for various deposition temperatures. The BMN films were crystallized with a monoclinic structure from $300^{\circ}C$ and the surface roughness slightly decreases with increasing deposition temperature. The capacitance density of the films increases with increasing deposition temperature and especially, films deposited at $400^{\circ}C$ exhibit a capacitance density of approximately $620nF/cm^2$. The crystallized BMN films with approximately 170 nm thickness exhibit breakdown strength above 600 kV/cm (${\leq}10V$) irrespective of deposition temperature and a leakage current density of approximately $2{\times}10^{-8}A/cm^2$ at 590kV/cm (at 10 V).

• Bulletin of the Korean Chemical Society
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• 제17권11호
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• pp.1000-1004
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• 1996

A random walk simulation was used to determine the triplet exciton density and annihilation rate for a two dimensional lattice of naphthalene choleic acid with small amount of β-methylnaphthalene (BMN). The results demonstrate that energy transfer efficiency (α) increases as density increases and the annihilation begins to become significant at triplet exciton densities higher then 10-3/sites. Another simulation was carried out to determine annihilation rate and unimolecular decay rate in the absence of BMN. The results indicate that the annihilation rate is equal to the unimolecular decay rate at the density of 1.2×10-3/sites.

• 한국전기전자재료학회논문지
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• 제13권6호
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• pp.478-484
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• 2000

The structural changes and the microwave dielectric properties of $Ba_{1-x}$/A$_{x}$/(Mg$_{1}$3//Nb$_{2}$3/)O$_3$(A=Sr, Ca=x0, 0.2, 0.4, 0.6, 0.8, 1.0) were investigated. The densities of samples are gradually decreased with increasing x(BMN=6.1, SMN=5.22 and CMN=4.26 g/m$^3$)The crystal structure of BMN was untilting of oxygen octahedral. The structural changes of BSMN showed the antiphase tilting at x>0.4, and those of BCMN showed the antiphase tilting at 0.20.8. The variation of dielectric constant with Sr was small(BMN=32, SMN=30) However the variation with Ca was large the highest value was 42 at Ca=0.2(CMN=25) The maximum quality factor was 68,000 GHz at Sr=0.2 and the minimum quality factor was 3,000 GHz at Ca=0.2 (BMN=35,000, SMN=20,000 and CMN=23,000 GHz) The temperature coefficients of resonant frequency of BSMN were about 2 times larger than those of BCMN in all composition.ion.

• Transactions on Electrical and Electronic Materials
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• 제8권2호
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• pp.84-88
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• 2007

[ $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ ] (BZN), $Bi_2Mg_{2/3}Nb_{4/3}O_7$ (BMN), and $Bi_2Cu_{2/3}Nb_{4/3}O_7$ (BCN) pyrochlore thin films were prepared on $Cu/Ti/SiO_2/Si$ substrates by pulsed laser deposition and the micro-structural and electrical properties were characterized for embedded capacitor applications. The BZN, BMN, and BCN films deposited at $25\;^{\circ}C$ and $150\;^{\circ}C$, respectively show smooth surface morphologies and dielectric constants of about $39\;{\sim}\;58$. The high dielectric loss of the films deposited at $150\;^{\circ}C$ compared with films deposited at $25\;^{\circ}C$ was attributed to the defects existing at interface between the films and copper electrode by an oxidation of copper bottom electrode. The leakage current densities and breakdown voltages in 200 nm thick-BMN and BZN films deposited at $150\;^{\circ}C$ are approximately $2.5\;{\times}\;10^{-8}\;A/cm^2$ at 3 V and above 10 V, respectively. Both BZN and BMN films are considered to be suitable materials for embedded capacitor applications.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1988년도 추계학술대회 논문집
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• pp.105-107
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• 1988

The dielectric properties of complex perovskite compound Sr$(Mg_{1/3}Mb_{2/3})$$O_3$-Ba$(Mg_{{1/3}Nb_{2/3})$$O_3$(BMN) system were investigated as a function of composition and sintering time. In the case of the specimens sintered at $1650^{\circ}C$ for same time, dielectric constant and dielectric loss were increased with increasing the mole ratio of BMN. The maximum temperature coefficient of resonant frequency was found in composition Ba$(Mg_{{1/3}Nb_{2/3})$$O_3$. In the case of the specimens with same composition, dielectric constant and dielectric loss were slightly increased with increasing the sintering time. As the sintering time was increased, the temperature coefficient of resonant frequency for SMN was slightly increased, however, that of BMN and ($Sr_{1/2}Ba_{1/2}$) ($Mg_{1/3}Ta_{2/3}$)$O_3$ was largely depended on sintering time.