• Journal of the Korean Magnetics Society
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• v.4 no.1
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• pp.44-47
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• 1994

High $T_{c}$ superconducting $Y_{1}Ba_{2}Cu_{3}O_{7-\delta}$ thin film was grown up for c-axis orientation by epitaxial growth method on $LaAlO_{3}$ single crystal substrate. The crystal structures of this thin film were found to be c-axis orientation by X-ray diffraction patterns. Hall effect and resistivity measurements were made by van der Pauw method. Hall resistivity was calculated from the magnetoresistivity by considering thermomagnetic effect. The relation was $pH=p_{s}tan{\alpha}_{n}-QBT\frac{S_s}{K_s}$ The measured Hall resistivity and the calculated one are in good agreement each other.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.12
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• pp.2010-2015
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• 1989

A SOI was fabricated by the FIPOS technique using n/p+/p silicon structure. Fabricated silicon island which has 3\ulcorner thickness and 100\ulcorner width was investigated by measuring van der Pauw resistivity, Hall mobility, dielectric breakdown voltage and leakage current. Hall mobility of the SOI was measured to be 300-500cm\ulcornerV.sec and its breakdown field was 1-2 MV/cm. The cross-sectional geometries of the SOI island were examined by SEM and optical microscope.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.53-63
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• 1998

The Cd1-xZnxS thin films were grown on the Si(100) wafers by a hot wall epitaxy method (HWE). the source and substrate temperature are 600℃ and 440℃, respectively. The crystalline structure of epilayers was investigated by double crystal X-ray diffraction (DCXD). Hall effect on the sample was measured by the van der Pauw method and the carrier density and mobility dependence of Hall characteristics on temperature was also studied. In order to explore the applicability as a photoconductive cell, we measured the sensitivity (γ), the ratio of photocurrent to darkcurrent (pc/dc), maximum allowable power dissipation (MAPD), spectral response and response time. The results indicated that the best photoconductive characteristic were observed in the Cd0.53Zn0.47S samples annealed in Cu vapor comparing with in Cd, Se, air and vacuum vapour. Then we obtained the sensitivity of 0.99, the value of pc/dc of 1.65 × 107, the MAPD of 338mW, and the rise and decay time of 9.7 ms and 9.3 ms, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.1
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• pp.1-5
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• 2000

Optical and electrical properties of GaSe:Er\ulcorner single crystals grown by the Bridgenman technique have been investigated by using optical absorption and h\Hall-effect measurement system. The Hall coefficients were mea-sured by using a high impedance electrometer in the temperature range from 360K to 150K. The temperature dependence of hole concentration show the characteristic of a partially compensated p-type semiconductor. Carrier density(N\ulcorner) of GaSe doped with Erbium was measured about 3.25$\times$10\ulcorner [cm\ulcorner] at temperature 300K, which was higher than undoped specimen. Photon energy gap (E\ulcorner) of GaSe:Er\ulcorner specimen was measured about 1.79eV.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.157-158
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• 2006

$CdS_{0.69}Se_{0.31}$ single crystal grown by sublimation method. Hall effect measurement were carried out by the Van der Pauw method. The measurement values under the temperature were found to be carrier density $n\;=\;1.95\;{\times}\;10^{23}m^3$, Hall coefcient $RH\;=\;-3.21\;{\times}\;10^{-5}m^3/c$, conductivity ${\sigma}\;=\;362.41\;{\Omega}^{-1}m^{-1}$, and Hall mobility ${\mu}\;=\;1.16\;{\times}\;10^{-2}m^2/v.s$.

• Korean Journal of Crystallography
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• v.7 no.1
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• pp.44-56
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• 1996

CuInTe2 synthesised in a horizontal electric furnace was found to be polycrystalline. Single crystals of CuInTe2 were grown with the vertical Bridgman technique. The structure, Hall effect of the crystals were measured in the temperature range 30 to 293K. Both the polycrystals and single crystals of CuInTe2 were tetragonal in structure. The lattice constants of the polycrytals were measured as a=6.168Å and c=12.499Å, with c/a=2.026, these of the single crystals were measured as a=6.186Å and c=12.453Å, with c/a=2.013. The growth plane of the oriented single crystals was confirmed to be a (112) plane from the back-reflection Laue patterns. The Hall effect of the CuInTe2 single crystals was measured with the method of van der Pauw The Hall data of the samples measured at room temperature showed a carrier concentration of 2.14×1023holes/m3, a conductivity of 739.58Ω-1m-1, and a mobility of 2.16×10 -2m 2/V·s for the sample perpendicular to the c-axis. Values of 1.51×1023holes/m3, 717.55Ω-1m-1, and 2.97×10-2 m2/V·s were obtained for the sample parallel to the c-axis. The Hall coefficients for the samples both perpendicular and parallel to the c-axis in the temperature range 30K to 293K were always positive values. Thus the CuInTe2 single crystal was determined to be a p-type semiconductor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.62-65
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• 1997

Indium nitride thin films were deposited on Si(100) substrates by reactive sputtering method. The metallic indium target was sputtered by nitrogen gas with rf sputtering equipment. The surface morphology and cross-section of the InN thin films were investigated by scanning electron microscopy. The crystal orientations were investigated by X-ray diffraction and the Hall effect were measured with van der Pauw method. The indium nitride thin film showed high Hall mobility(215$\textrm{cm}^2$/V-sec) at 5mTorr total pressure and rf power 60W.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.32-43
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• 1996

A $CdIn_{2}Te_{4}$ single crystal was grown by modified veritical bridgman method. The $CdIn_{2}Te_{4}$ single crystal was evaluated to be tetragonal by the powder method. The $CdIn_{2}Te_{4}$ single crystal was confirmed to be grown with its c axis along the lengthe of the boule by the Laue reflection method. Hall effect of $CdIn_{2}Te_{4}$ single crystal was estimated by van der pauw method from 293 K to 30 K. Hall data of the sample perpendicular to c axis was $n=8.75{\times}10^{23}electrons/m^{3},\;R_{H}=7.14{\times}10^{-5}m^{3}/C,\;{\sigma}=176.40{\omega}^{-1}m^{-1},\;{$\mu}=3.41{\times}10^{-2}m^{2}/V.s$ and the sample parallel to c axis was $n=8.61{\times}10^{23}electrons/m^{3},\;R_{H}=7.26{\times}10^{-5}m^{3}/C,\;{\sigma}=333.38{\omega}^{-1}m^{-1}\;and\;{$\mu}=2.42{\times}10^{-2}m^{2}/V.s$ for room temperature. The value of Hall coefficient on sample perpendicular or parallel to c axis were positive. There $CdIn_{2}Te_{4}$ single crystal was p-type semiconductor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.126-130
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• 1995

$CdS_{1-x}Te_{1-x}$ polycrystalline thin films were fabricated from CdS and CdTe powder by co-evaporation method at $10^{-6}$ Torr. The Optimum evaporation condition was substrate temperature $T_{s}$=$150^{\circ}C$, evaporation time t=30 min. XRD spectrums indicated that the crystal structure chanced from zinc blonde (x$\leq$0.22) to wurtzite (x$\geq$0.96) through mixed structure (0.22$\leq$0.74) as composition value x increase to CdS. Conductive type was n-type by hot point probe method. van der Pauw method was not applicable for x<0,5 due to high hall voltages, Electrical resistivity and Hall carrier mobility were decreased as x increase, while Hall carrier concentration was increased. The optical bandgap of $CdS_{1-x}Te_{1-x}$ polycrystalline thin films measure d at R.T. had quardratic form and the bowing parameter was fitted as 1.98eV for theoretical value of 2.0eV. I-V characteristics of In/CdTe/$CdS_{x}Te_{1-x}$Au Schottky diodes showed that CdS-rich one had better forward characteristics than CdTe-rich one.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.77-78
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• 2008

ZnO thin films were deposited on glass substrates by pulsed laser deposition (PLD) at various oxygen pressures. We observed structural, electrical and optical properties of ZnO films. Structural properties were analysed by XRD and FE-SEM. Electrical properties for applications of transparent thin film transistors (TTFTs) were measured by hall measurement using van der pauw methods at room temperature. In order to apply in transparent devices, we measured transmittance, and optical bandgap energy was calculated by Tauc's equation. The results showed that ZnO films deposited at 200mTorr oxygen pressure were applicable to channel layers of transparent TFTs. It had high hall mobilities ($52.92cm^2$/V-s) and suitable transmittance at visible wavelength region (above 80%).