http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Pb(Zr, Ti)O₃ 강유전체 박막의 스퍼터링 증착과 후속열처리
장지근(G. K. Chang),박재영(J. Y. Park),윤진모(J. M. Yoon),임성규(S. K. Lim),장호정(H. J. Chang) 한국진공학회(ASCT) 1997 Applied Science and Convergence Technology Vol.6 No.1
Pt/Ti/SiO₂/Si 기판상에 고주파 마그네트론 스퍼터링 방식으로 PZT 박막 [두께: 3000Å]을 증착하고 RTA 방식으로 후속 열처리[열처리온도: 550℃~650℃, 열처리 시간: 10초~50초]를 실시하여 직경 0.2㎜ 소자의 FECAPs(ferroelectric capacitors)를 제작하였다. 제작된 커패시터의 유전상수(ε_r)와 잔류분극(2P_r)은 650℃로 30초간 열처리한 시편에서 ε_r(1kHz) = 690, 2Pr(-5V~5V sweep) = 22 μC/㎠로 가장 높게 나타났으며 유전 정접(tan δ)과 누설전류(J_ㅣ)는 600℃에서 30 초간 열처리한 시편에서 tan δ(≥ 10kHz)≤0.02, J_l(5V)=3 μA/㎠로 가장 낮게 나타났다. FECAPS(ferroelectric capacitors) have been fabricated by RF magnetron sputtering deposition of 3000Å PZT thin films on the Pt/Ti/SiO₂/Si substrates and post-annealing with the temperature of 550℃~650℃ for 10 sec ~50 sec in a RTA system. The electrical characteristics of the fabricated capacitors showed the highest dielectric constant and remanent polarization[ε_r(1kHz) = 690, 2P_r(-5V~5V sweep) = 22 μC/㎠] in the samples annealed at 650℃ for 30 sec, while the lowest tangent loss and leakage current[tan δ(≥10kHz)≤0.02, J_l/5V) = 3 μA/㎠] in the samples annealed at 600℃ for 30 sec.
로터 공력 해석을 위한 Actuator Surface Method 개선 연구
박재영(J.Y. Park),강선오(S.O. Kang),태명식(M.S. Tai),오세종(S.J. Oh),박동훈(D.H. Park) 한국전산유체공학회 2019 한국전산유체공학회지 Vol.24 No.2
In this study, improvements on up-to-date actuator surface method are proposed to enhance the prediction capability and universality for rotor aerodynamic analysis. In order to improve accuracy for analysis of high-solidity rotor, the correction equation for reference line velocity was newly derived to take into account influences of neighboring blades. To describe more realistic flow field and wake around blades, source-doublet panel method was adopted to calculate the momentum source distribution along chord-wise direction which reflects the characteristics of sectional airfoil and flow condition. The validity of proposed methods is evaluated by carrying out the analyses for rectangular wing and open rotor, and comparing with available experimental and computational results. It is confirmed that suggested methods can provide improvement on prediction of velocity field and wake trajectory, as well as aerodynamic performance.