• Electrical & Electronic Materials
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• v.6 no.6
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• pp.565-572
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• 1993

LPE(liquid phase epiraxy)법으로 성장시킨 $Al_{x}$ Ga$_{1-x}$As (0.15.leq.x.leq.0.67) 에피층의 구조적 특성을 이중결정 X-선 회절장치를 사용하여 조사하였다. GaAs기판과 $Al_{x}$ Ga$_{1-x}$As 에피층의 격자상수 차이로 인해 피이크가 분리되었고 이는 조성비가 증가함에 따라 선형적으로 증가하였다. 그리고 조성비는 Vegard의 법칙으로 구한 값과 기판 및 에피층 피이크 사이 각도분리(.DELTA..theta.)를 측정함으로써 구한 값이 일치하였으며 이때 관계식은 .DELTA..theta.=354.x을 얻었다. 또한 성장된 에피층은 compressive stress를 받고 있으며 조성비(x)가 0.15에서 0.67로 증가함에 따라 응력은 증가하였으며 그리고 피이크의 반치폭으로 부터 계산된 전위밀도가 역시 증가하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.6
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• pp.580-584
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• 1999

The synthesis and characterization of intercalated compound of decansulfonate into hydrated nickel is presented. The compound shows a layered structure as determined by high temperature powder X-ray diffraction (HTXRD). The layer distance of the product is increased from 24.7 $\AA$ to 30.5 $\AA$ by increasing the temperature which is in turn accomplished by changing the structure of the intercalated nickel compound. From the X-ray diffraction data and the decanesulfonate size, the orientation of the decanesulfonate onto the nickel layer is determined. The molecular axis of the decanesulfonate with bilayer structure is tilted to the perpendicular of the nickel layer.

• Korean Journal of Materials Research
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• v.7 no.12
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• pp.1041-1046
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• 1997

본 연구에서는 분자선 에피택시 방법으로 비대칭 AIAs/GaAs(001)이중 장벽, 삼중장벽구조를 성장한 수 이를 이용하여 2단자 소자를 제작하여 전기적 특성을 분석하였다. 에피층은 쌍결정 X-ray회절 분석과 단면투과 전자현미경을 이용하여 결정성 및 격자 정합성을 확인하였다. 전기적 성능을 보다 향상시키기 위해 n-GaAs에 대한 오믹 접촉등의 소자 제작 공정을 최적화하였다. 삼중장벽 구조를 이용하여 제작한 소자의 전기적 특성 연구 결과 두개의 주요 공진 터널링 전류 피크 사이에 X-valley에 의한 구조를 확인할 수 있었으며, 이중 장벽구조에 제2의 양자우물 구조를 첨가함으로써 낮은 전압위치에서 전류 피크가 향상하는 결과를 얻었다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.4
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• pp.408-413
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• 1995

We investigated the effect of mechanical backside damage upon minority carrier recombination lifetime measurement in Czochralski silicon substrate by laser excitation/microwave reflection photoconductance decay method. The intensity of mechanical damage was evaluated by X-ray double crystal rocking curve, X-ray section topography and wet oxidation/preferential etch methods. The data indicate that the higher the mechanical damage intensity, the lower the minority carrier lifetime, and the threshold full width at half maximum value which affect minority carrier lifetime measurement is about 13 secs.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.71-76
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• 1998

Crystal structure of Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II0 has been determined by X-ray crystallography. Crystal data : (Pd(C2H8N2)2.Pd(C2O4)2), Fw=509.04, Monocline, Space Group P21/c (no=14), a=6.959(2), b=13.506(2), c=15.339(2) Å, β=99.94(3), Z=4, V=1420 Å3, Dc=2.380 gcm-3, μ=25.46cm-1, F(000)=992. The intensity data were collected with Mo-Kα radiation (λ=0.7107 Å) on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-square methods using unit weights. The final R and S values were R=0.021, Rw=0.030, Rall=0.032 abd S=2.1 for 1472 observed reflections. The essentially planar complex anions form diade of interplanar distances of 3.41 Å and their diads are stacked along aaxis with interplanar separation of 3.44 Å.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.36-41
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• 1998

Intercalation compounds of alkyl sulfonates into layered double hydroxides (LDH) have been directly synthesized. From the X-ray diffraction data and the alkyl sulfonates size, the orientation of the intercalated alkyl sulfonate into the layered double hydroxide was determined. The intercalated alkyl sulfonate is arranged with molecular chain perpendicular to the hydroxide layer with an antiparallel pattern.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.4
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• pp.318-323
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• 2000

The intercalated compounds of alkylsulfonates into hydrated zinc were synthesized. From the high temperature powder X-ray diffraction (HTXRD), FT-IR, and molecular size, the temperature dependence of orientation for the intercalated alkylsulfonates were determined. In the temperatures range 1, alkylsulfonates were intercalated into hexa aqua zinc layer with the bilayer structure of $32.9^{\circ}$angle for ${Zn(H_2O_4]^{2+}[C_nH_{2n+1}SO_3]_2\;^-$. In the temperatures range 2, alkylsulfonates were intercalated into tetra aqua zinc layer with the bilayer structure of $55.2^{\circ}$angle for ${Zn(C_nH_{2n+1}SO_3)_2$. In the temperatures range 3, alkylsulfonates were directly bonded to zinc ion with the bilayer structure of $76.5^{\circ}$angle for ${Zn(C_nH_{2n+1}SO_3)_2$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.6
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• pp.225-230
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• 2022

A new two-fold interpenetrating two-dimensional (2D) Tb(III) metal-organic framework (MOF), [Tb(p-XBP4)_2.5(H₂O)₂]·W(CN)₈ (1), was prepared using a p-XBP4 (N,N'-p-phenylenedimethylenbis(pyridin-4-one)), Cs₃[W(CN)₈], and Tb(NO₃)₃·6H₂O. The single crystal X-ray diffraction indicated that Tb-MOF exhibits a unique two-fold interpenetrating 2-D framework. It was also characterized through Fourier transform infrared spectroscopy (FTIR), and single and powder X-ray diffraction. To probe the molecular magnetic behavior, the magnetic properties of Tb-MOF were investigated by direct-current (DC) and alternating-current (AC) magnetic susceptibilities measurements and discussed.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1816-1821
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• 2003

The sapphire wafer for blue light emitting device was manufactured by the implementation of the chemical and mechanical polishing process. The surface polishing of crystalline sapphire wafer was characterized by zeta potential measurement. The reduction process with the alkali slurry provides the surface chemical reaction with sapphire atoms. The poly-urethane pad also provides the frictional force to take out the chemically-reacted surface layers. The surface roughness was measured by the atomic force microscope and the crystalline quality was characterized by the double crystal X -ray diffraction analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.1
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• pp.85-91
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• 2004

The sapphire wafers for blue light emitting devices were manufactured by the implementation of the surface machining technology based on micro-tribology. This process has been performed by chemical and mechanical polishing process. The sapphire crystalline wafers were characterized by double crystal X-ray diffraction. The sample quality of sapphire crystalline wafer at surfaces has a full width at half maximum of 89 arcsec. The surfaces of sapphire wafer were mechanically affected by residual stress during the polishing process. The wave pattern of optical interference of sapphire wafer implies higher abrasion rate in the edge of the wafer than its center from the Newton's ring.