• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2002년도 추계학술대회 발표 논문집
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• pp.34-46
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• 2002

Si-O-C-H films with a low dielectric constant were deposited on a p-type Si(100) substrate using a mixture gases of the bis-trimethylsilyl-methane (BTMSM) and oxygen by an inductively coupled plasma chemical vapor deposition (ICPCYD). High density plasma of about $~10^{12}\textrm{cm}^{-3}$ is obtained at low pressure (<400 mTorr) with rf power of about 300W in ICPCVD where the BTMSM and $O_2$ gases are fully dissociated. Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectroscopy (XPS) spectra show that the film has $Si-CH_3$ and OH-related bonds. The void within films is formed due to $Si-CH_3$ and OH-related bonds after annealing at $500^{\circ}C$ for the as-deposition samples. The lowest relative dielectric constant of annealed film at $500^{\circ}C$ is about 2.1.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.31-34
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• 2003

($Ba_{0.6-x}Sr_{0.4}Ca_x)TiO_3$ (BSCT) (x=0.10, 0.15, 0.20) powder, prepared by the sol-gel method, were mixed with organic vehicle and the BSCT thick films were fabricated by the screen-printing techniques on alumina substrates using the BSCT paste. The structural and the electrical properties were investigated for various composition ratio and sintering temperature. BSCT thick film thickness, obtained by four printings, was approximately 110 ~ 120 ${\mu}m$. The Curie temperature and dielectric constant at room temperature were decreased with increasing Ca content. The relative dielectric constant, dielectric loss and tunability of the BSCT(50/40/10) specimen, which was sintered at $1420^{\circ}C$ and measured at 1MHz, were about 910, 0.46% and 9.28% at 5kV/cm, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1621-1623
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• 2004

The $Pb(Zr_{0.52}Ti_{0.48})O_3/(Ba_{0.6}Sr_{0.4})TiO_3$ [PZT(52/48)/BST(60/40)] heterolayered thin films were deposited on Pt/Ti/$SiO_2$/Si substrates by using the RF sputtering method with RF powers of 60,70,80,90[W]. All thin films showed the peaks of the tetragonal phase. Increasing the RF power, dielectric constant and loss of the PZT(52/48)/BST(60/40)] heterolayered thin films were decreased. The thickness ratio of PZT and BST thin films was 1/1. The relative dielectric constant and the dielectric loss of the PZT(52/48)/ BST(60/40) heterolayered thin films were 562 and 13%, respectively.

• The Korean Journal of Ceramics
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• 제1권1호
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• pp.13-20
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• 1995

Effects of thermal annealing on the dielectric/piezoelectric properties of $Pb(Zn, Mg)_{1/3}Nb_{2/3}O_3-PbTiO_3$ ceramics (PZMNPT) with Zn/Mg=6/4) were examined across the rhombohedral/tetragonal morphotropic phase boundary (MPB). Both the relative dielectric permittivity ($\varepsilon$r)and the piezoelectric constant($d_33$)/electromechanical coupling constant ($k_p$)were increased by thermal annealing ($800^{\circ}$~$900^{\circ}C$) after sintering at $1150^{\circ}C$ for 1 hr. Based on the dielectric analysis using the series mixing model and the concept of a random distribution of the local Curie points, the observed improvements in the dielectric and piezoelectric properties of PZMN-PT were interpreted in terms of the elimination of PbO-rich amorphous intergranular layers(~1nm) induced by thermal annealing. A concrete evidence of the presence of amorphous grain-boundary layers in the unannealed (as-sintered) specimen was obtained by examining the structure of intergranular region using a TEM.

• 한국토양비료학회지
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• 제33권1호
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• pp.15-23
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• 2000

비닐 튜브로 절연한 센서 봉을 토양에 박아 콘덴서로 하고, RC 발전식으로 토양의 유전율을 측정하는 수분 센서의 반응 특성을 조사하였다. 출력은 표준 콘덴서에 비교된 상대 카피씨티, C였는데, 이 카파시티의 등가 회로는 병렬로 연결된 기본 카파씨티와 센서 봉 카파씨티인데, 센서봉 카파씨티는 다시 직렬로 연결된 센서봉 절연 튜브 카파씨티와 센서봉 사이 측정 부위 유전율, U에 따라 변하는 카파시티로 구성되어, 아래 반응 수식에 따라 작동하였다. $$\frac{1}{C-B}=\frac{k}{U}+Z$$는 기본 콘덴서에서 유래하는 상대 카파시티로서 불변 값이며, k은 측정부위 유전율에 따라 출력에 관여하는 상수로서, 토양과 접촉하는 센서봉의 외경과 센서봉 간격 및 길이 등의 기하학적 배치로 결정되는 값으로 거의 불변 값이고, Z은 비닐 튜브와 그 안에 금속봉 사이의 공기 층으로 결정되는 값으로 이론상으론 불변 값이나 만약 이 센서를 토양에 설치할 때 토양과 센서봉 사이에 틈이 생기면, 이 값에 변화가 온다. 따라서, 이 토양 수분 측정기는 현장 매설후 Z 값을 보정하여야 하며 그후 Z값이 변화하지 않도록 센서봉이 충격을 받지 않게 관리하여야 한다.

• 전자공학회논문지A
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• 제33A권2호
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• pp.69-77
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• 1996

We analyzed wideband propagation characteristics of a microstrip transmission line based on FR-4 composite substrate using the wideband complex dielectric constant model and the phenomenological loss equivalence method. The loss calculated by constant relative permittivity and loss tangent is greatly overestimatd compared to that calculated by the frequency-dependent complex relative permittivity. This wideband analysis can be helpful to characterize high-speed and high-density transmission lines associated with the wideband dielectric characteristics and shows that the FR-4 composite substrate has high potential of high frequency circuit applications in terms o fthe propagation loss.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.347-349
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• 1999

We have fabricated insulating thin films using p-hexadecoxyphenol(p-Hp) that was formed phenol-formaldehyde resin of crosslinked structure from reaction with formaldehyde by LB technique. For fabricated MIM device, the possibility for insulating layers of electronic were investigated by electrical properties of their LB films according to crosslinking of LB films current-voltage (I-V) properties and frequency-capacitance (C-F) characteristics. We have provided evidence for the high insulating performance of phenol-formaldehyde thin films by the LB method. Conductivity of their LB films was as follows: pure water > 1 % aq. Formaldehyde > heat treatment, in the current-voltage (I-V) characteristics. It is demonstrated that insulation properties of crosslinked p-HP LB films were improved. In capacitance-frequency properties, the heat-treated p-HP LB films for crosslinking showed a low relative dielectric constant.

• 한국세라믹학회지
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• 제34권6호
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• pp.629-635
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• 1997

The effects of the annealing atmospheres(O2, N2) and sintering additives that Bi2O3 is a major composition on the microwave dielectric and sintering propertie of (1-x)CaTiO3-xLaAlO3 system were investigated. The annealing atmospheres and the increase of annealing time after sintering did not affect the relative dielectric constant($\varepsilon$r) and temperature coefficient of resonant frequency($\tau$f) of (1-x)CaTiO3-xLaAlO3 system. However, the Q.f0 values of (1-x)CaTiO3-xLaAlO3 were very sensitive to annealing atmospheres. As the annealing time increased under O2 atmosphere the Q.f0 values of (1-x)CaTiO3-xLaAlO3 enhanced untill 10 hrs in 0.3$\leq$x$\leq$0.6 region, but degraded over that time. The increasing rate of Q.f0 value increased wth increasing x. On the other hand, as the annealing time increased under N2 atmosphere the Q.f0 values were constant in x$\leq$0.6 region, increased gradually in x$\geq$0.7 region. When 0.97Bi2O3-0.03Al2O3 and 0.76Bi2O3-0.24NiO of 3wt% as sintering additives were added to (Ca0.5La0.5) (Ti0.5Al0.5)O3 (x=0.5) the sintering temperature of 1$600^{\circ}C$ was lowered to 140$0^{\circ}C$, and the relative dielectric constant($\varepsilon$r) and temperature coefficient of resonant frequency($\tau$f) were not nearly changed. The addition of 0.97Bi2O3-0.03Al2O3 and 0.76Bi2O3-0.24NiO of 3wt% to (Ca0.5La0.5)(Ti0.5Al0.5)O3 made the Q.f0 values to be lower about 15% and 34%, respectively.

• 마이크로전자및패키징학회지
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• 제27권4호
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• pp.91-96
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• 2020

Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3계 압전 단결정의 유전특성과 압전특성을 전계 및 압축응력 인가 조건 하에서 33-모드 방식으로 측정하였다. 110~140℃ 영역에서 저온 rhombohedral 구조에서 고온 tetragonal 구조로의 상전이가 관찰되었으며, cubic 구조로 변화하는 큐리온도는 165℃ 정도로 나타났다. 압축응력 및 전계 변화에 따른 분극의 크기변화를 측정하였다. 전계인가 분극 곡선의 기울기로부터 비유전율을 계산하였고, 인가되는 응력의 크기가 증가할수록 계산된 비유전율의 크기는 증가하고, 인가되는 전계의 크기가 증가할수록 비유전율의 크기는 감소하는 경향성을 나타내었다. 압축응력 및 전계 변화에 따른 변위 거동을 측정하였으며, 곡선의 기울기로부터 압전상수를 계산하였고 압력인가에 따른 상전이를 확인하였다. 수중 또는 의료용 초음파 발진자로 실제 응용할 경우 선형성을 유지하여 구동이 가능하기 위하여 소자 기구물을 형성하는 단계에서 인가하게 되는 압축응력의 크기와 구동 전계의 DC 바이어스의 크기를 적절하게 설계할 필요가 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1993년도 추계학술대회 논문집
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• pp.131-133
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• 1993

Plasma polymerized thin films were prepared using an interelectrode capacitively coupled gas flow type reactor. Hexamethyldisiloxane was chosen as the monomer to be used. The dielectric properties of the thin films have been investigated with the changes of discharge power, heat treatment temperature and frequency. The relative dielectric constant was increased with an increasing of discharge power, but was decreased with an increasing of heat treatment temperature.