2성분계 PZT 압전세라믹스의 Mole 比에 따른 전기적 특성에 관한 연구

설정식,이수대,강광용 경남대학교 환경문제연구소 1987 환경연구 Vol.9 No.-

Lead zirconate titanate (Pb (Zr_(x), Ti_(1-x)) O_(3)) piezoelectric ceramics were prepared from PbO, ZrO_(2) and TiO_(2). These oxides were wet ball-milled and were hot pressed at 1250℃ in 0_(2) for 4h at 50kg/cm^(2) finally, and were ascertained by x-ray diffraction experiments. Samples which were used for measurement, were classified into 5 types according to x-values and Curie temperatures determined for each samples, from the dielectric measurements at 1 KHz, are gradually lowered with the decrease of x-values and electromechanical coupling factors (k) which were calculated from the measurement of frequency-impedance relation are increased with the decrease of x-values. These results are fairly consistent with the ones reported previously.

광음향 효과를 이용한 고체의 열확산율 측정

설정식 慶南大學校 附設 基礎科學硏究所 1997 硏究論文集 Vol.10 No.-

A photoacoustic technique for the determination of thermal diffusivity of opaque and transparent solid is developed. The technique is fast and avoids some of the difficulties of conventional methods. Thermal diffusivities for aluminum and quartz are measured and found be in good agreement with literature values.

강탄성 Switching에 의한 격자점의 변위 특성을 이용한 Pb₃(PO₄)₂ 단결정의 자발변형 측정

이수대,설정식 慶南大學校 附設 基礎科學硏究所 1996 硏究論文集 Vol.9 No.-

In order to measure components of the spontaneous strain tensor by the switching phenomena of Pb₃(PO₄)₂ single crystals, we derived the formulae for translational displacement and rotational displacement of the lattice points by switching between each states in ferroelasticity. By using this formulae, we suggested the method and the process for measurement of components of the spontaneous strain tensor. The value of es11 was measured from the variation of radial component and the variation of azimuthal angle by switching between each states at Pb₃(PO₄)₂ single crystals and it was -0.0217±0.0001. In addition, the value of es13 which was measured from the variation of zenithal angle was 0.0066±0.0001.

Lead Germanate 단결정의 초음파 감쇠

이수대,채건식,김영국,설정식 慶南大學校 附設 基礎科學硏究所 1989 硏究論文集 Vol.1 No.-

The temperature dependence of the ultrasonic velocity of 10 MHz and the absorption coefficient in the 10-30MHz range by the pulse echo method were determined in lead germanate single crystal. The velocity of longitudinal 10 MHz ultrasound along the c axis changed anomalously at the phase transition point and the jump was approximately 50m/sec. Near Curie point, the relaxation time and the kinetic coefficient of electric polarization from the Landau-Khalatnikov theory were calculated as ?? sec and ??, respectively. At room temperature, the viscosity tensor were measured as, ?? in the MKS units.

Pb Ge Ti O 단결정의 상전이와 유전적 성질

이찬구,이수대,설정식 慶南大學校 附設 工業技術硏究所 1997 硏究論文集 Vol.15 No.1

강유전체 ?? 단결정을 χ=0.015, 0.021, 0.03의 조성에 대하여 Czochralski법으로 성장시켰으며, 성장시킨 단결정의 색상은 맑고 투명한 연한 노란색이었다. ?? 단결정의 유전상수와 자발분극의 온도특성을 조사하기 위하여 온도를 올리면서 실온에서 Curie 온도 위까지 측정하였다. 유전상수의 온도의존성에 대한 조사결과 ?? 단결정의 상전이 온도는 178℃, Curie상수는 c=1.17×10⁴K였다. χ=0.015인 단결정은 ??=152℃, Curie상수는 1.15×10⁴K이며, χ=0.021인 단결정은 ??=137℃, Curie상수는 1.25×10⁴K이고, χ=0.03인 단결정은 ??=142℃, Curie상수는 7.51×10³K이었다. 또한 ?? 단결정의 전기이력곡선 으로부터 얻은 자발분극 ??는 0.047 C/m²이고, 항전기장 ??는1.5×?? V/m이었다. 그리고 ?? 단결정의 자발분국은 ??는 0.025C/m²이고 항전기장은 ??는 1.1×?? V/m이었다. 한편 ?? 단결정의 상유전-강유전 상전이형태는 변위형과 질서-무질서형의 중간적 성질을 가졌다. Ferroelectric ??(χ=0, 0.015, 0.021, 0.03) single crystals were obtained from the melt by the Czochralski method. Grown crystals were pale brownish yellow and fully transparent. The temperature characteristics of dielectric constants, spontaneous polarization of ?? single crystals have been investigated in detail from room temperature up to above the Curie temperature. From the results of the these measurements, the following constants were obtaind : the Curie constant calculated from the slope above ?? are c=1.17×104 K, 1.15×104 K 1.25×104 K and c=7.51×103 K for χ=0, 0.015, 0.021 and χ=0.03 single crystals respectively. The spontaneous polarization ?? and the coercive electric field ?? estimated from the hysteresis loops which are 0.047 C/m², 1.5×?? V/m for ?? single crystal and 0.025 C/m², 1.1×?? V/m for ?? single crystal respectively. From the complex dielectric measurements and pyroelectric measurements. it was confirmed that the paraelectric-ferroelectric phase transition of ?? single crystals undergo a displacive second order phase transition at ??.

스크린 프린트 方法에 依한 CdS/Cu_(x)S 太陽電池 製作 및 特性조사

薛貞植,金永局 경남대학교 환경문제연구소 1982 환경연구 Vol.4 No.-

CdS/Cu_(x)S solar cells were prepared by using a screen printing method. A low resistivity CdS film was obtained by screen printing CdS paste on a glass substrate and then sintering it in N₂gas including a small amount of Cd vapor. CdS paste for screen printing was prepared by mixing loog CdS powder and 7g CdCl₂powder with propylen glycol(binder) in an agate mortar. CdCl₂was used as a flux. CdS paste was printed on a borosilicate glass substrate by a screen printing method, and then sintered at 640℃ in N₂gas for 1 hour using a furnace, a Cd metal was placed on the inlet side of N₂gas in the furnace and held at 400℃. The CdS film thus sintered had a resistivity of about 5~15Ω-cm, mobility μ_(e) of about 200~270㎠/Vㆍsec, a thickness of about 50~500㎛ and grain size of 5-lO㎛. Fabrication of a low resistivity CdS film and heat treatment in H₂gas after applying electrodes were very important factors in obtaining a high efficiency cell. Under AM1 sunlight simulator, the parameters for the typical cell are open-circuit voltage V_(DC)=0.4V, short-circuit current I_(SC)=5mA, fill factor FF=0.55 and conversion efficiency Л=1.12%.

광음향 효과를 이용한 흡수 분광법 연구

설정식 慶南大學校 附設 基礎科學硏究所 1998 硏究論文集 Vol.12 No.-

The absorption spectrometry by using photoacoustic effect is a very useful method for the study of materials. Conventional absorption spectrometry could not yield the absorption spectra of the powder type samples, Methyl orange, Acid orange and NiO. Photoacoustic spectra were obtained from these materials and these were compared with the absorption spectra of the powder samples dissolved in distilled water and the absorption spectra of the NiO crystal obtained by the conventional method. The results show a great deal of consistency between the two sets of spectra.

Pick-up 광학계용 비구면 대물렌즈 설계

정진호,설정식 慶南大學校 附設 基礎科學硏究所 1995 硏究論文集 Vol.7 No.-

We designed two aspheric objective lenses(N.A=0.54915 and N.A=0.46764) for optical disk drive by DLS optimizing method and obtained that least spot size is 1㎛ and Strehl Ratio is 0.98. The glasses of objective lenses are light and have low thermal variation. This lenses have the performance of diffraction limit. Therefore, it is used the optical unit of magneto optical disk drive system.

Lead Molybdate 단결정의 탄성광학적 효과

이수대,설정식 慶南大學校 附設 基礎科學硏究所 1990 硏究論文集 Vol.2 No.-

The structure of the lead molybdate single crystals were investigated by the X-ray diffraction pattern. The lattice constants of the lead molybdate were a=b=5.44Å and c=12.12Å. The refractive index of the lead molybdate single crystals have been measured from room temperature to 300℃ with the Brewster angle. The refractive indices of the ordinary ray and extra ordinary ray were 2.3629 and 2.2511 at room temperature. The stress-optical coefficients q₁₂, q ₁₃and q₃₁ to be obtained by the Mach-Zehnder in teferometer were 1.027x????, 1.861x???? and 0.019x????m²/N at room temperature.

LiTaO₃ 단결정의 임피던스 완화현상에 관한 연구

이수대,설정식 慶南大學校 附設 基礎科學硏究所 1996 硏究論文集 Vol.9 No.-

The impedance relaxation of LiTaO₃ single crystals has been studied as a function of frequence range from 10 Hz to 10 MHz at temperatures range from 30 to 1000℃. The complex impedance data were analyzed in Cole-Cole type equivalent circuits by the computer fitting method. It was found that two dispersion processes with non-ideal relaxation had been existing in LiTaO₃ single crystal. one due to the carrier mobility and the other resulting from intrinsic polarization of ferroelectric material. Based on an equivalent circuit the impedance relaxation expression was proposed to describe the impedance behavior of LiTaO₃ single crystals. From this study. activation energy for relaxation process was 1.15eV and relaxation time was about 10-5 sec.