• 한국세라믹학회지
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• 제22권2호
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• pp.51-57
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• 1985

Silicon single crystals were grown bynon-seeded vertical Brdgmen-Stockbarger technique. Optimum growth rate appeared 5mm/hr in the system. It was identified that the preferential orientation using by the optical microscope resulted in <100> direction.

• Journal of Mechanical Science and Technology
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• 제15권8호
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• pp.1188-1195
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• 2001

A numerical analysis has been carried out to investigate the influences of thermosolutal convection on the heat and mass transfer and solute segregation in crystals grown by the vertical Bridgman technique. The governing equations are solved by a finite-volume method using the power law scheme and the SIMPLE algorithm in which body-fitted coordinate system has been used. A primary convective cell driven by thermal gradients forms in the bulk of the domain, while a secondary convective cell driven by solutal gradients forms near interface. As the solutal Rayleigh number increases, secondary cell becomes to be stronger and has a great influence on the radial concentration along the interface.

• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4215-4219
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• 2022

The Cd_0.95Mn_0.05Te_0.98Se_0.02 (CMTS) ingot was grown by the vertical Bridgman technique at low pressure. All wafers showed high resistivity, which suggests potential as a room-temperature semiconductor detector. The resistivity of the CMTS planar detector was 1.47 × 10¹⁰ Ω·cm and mobility lifetime product of electrons was 1.29 × 10^-3 cm²/V. The spectroscopic property with Am-241 and Co-57 was evaluated. The energy resolution about 59.5 keV gamma-ray of Am-241 was 11% and the photo-peak of 122 keV gamma-ray from Co-57 was clearly distinguished. The result shows the first detector-grade CMTS in the world and proves CMTS's potential as a radiation detector operating at room temperature.

• 한국자기학회지
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• 제16권3호
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• pp.178-181
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• 2006

본 연구에선는 수직 Bridgman 법으로 묽은 자성 반도체 $Si_{1-x}Mn_xTe_{1.5} $ 단결정을 성장시켜 Mn의 조성비 변화에 따른 광학적, 전지적, 그리고 자기적 특성을 조사하였다. X-선 회절 실험으로부터 육방정계(hexagonal) 구조임을 확인하였다. 광흡수 측정으로부터 에너지 띠 간격은 조성비 x와 온도 증가에 대하여 감소함을 보였다. 성장시킨 시료의 경우 강자성 특성을 나타내었으며, Curie 온도는 80K 이상이었다. Mn의 조성비가 증가함에 따라 평균 자기 모멘트와 보자력 값은 증가하였다.

• 한국결정성장학회지
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• 제9권6호
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• pp.535-541
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• 1999

Low-dislocation-density large-diameter GaAs single crystals with low-residual-strain have been strongly required. We have developed dislocation-free 3-inch Si doped GaAs crystals for photonic devices, and low-dislocation-density low-residual-strain 4-inch to 6-inch semi-insulating GaAs crystals for electronic devices by Vertical Bridgman(VB) technique. We confirmed that VB substrates with low-residual-strain have higher resistance against slip-line generation during MBE process. VB-GaAs single crystals show uniform radial profile of resistivity reflecting to the flat solid-liquid interface during the crystal growth. Uniformity of micro-resistivity of VB-GaAs substrate is much better than of the LEC-GaAs substrate, which is due to the low-dislocation-density of VB-GaAs single crystals.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.278-281
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• 2003

The p-CIn2Te4 single crystal was grown in the three-stage vertical electric furnace by using Bridgman method. The quality of the grown crystal has been investigated by the x-ray diffraction and the photoluminescence measurements. From the photoluminescence spectra of the as-grown CdIn2Te4 crystal and the various heat-treated crystals, the (Do, X) emission was found to be the dominant intensity in the photoluminescence spectrum of the CdIn2Te4:Cd, while the (Ao, X) emission completely disappeared in the CdIn2Te4:Cd. However, the (Ao, X) emission in the photoluminescence spectrum of the CdIn2Te4:Te was the dominant intensity like an as-grown CdIn2Te4 crystal. These results indicated that the (Do, X) is associated with VTe acted as donor and that the (Ao, X) emission is related to VCd acted as acceptor, respectively. The p-CdIn2Te4 crystal was found to be obviously converted into the n-type after annealing in the Cd atmosphere. The origin of (Do, Ao) emission and its TO phonon replicas is related to the interaction between donors such as VTe or Cdint, and accepters such as VCd or Teint. Also, the In in the CdIn2Te4 was confirmed not to form the native defects because it existed in the stable form of bonds.

• 센서학회지
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• 제15권6호
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• pp.379-385
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• 2006

Single crystal of p-$CdIn_{2}Te_{4}$ was grown in a three-stage vertical electric furnace by using Bridgman method. The quality of the grown crystal has been investigated by x-ray diffraction and photoluminescence measurements. From the photoluminescence spectra of the as-grown $CdIn_{2}Te_{4}$ crystal and the various heat-treated crystals, the ($D^{o}$, X) emission was found to be the dominant intensity in the photoluminescence spectrum of the $CdIn_{2}Te_{4}$:Cd, while the ($A^{o}$, X) emission completely disappeared in the $CdIn_{2}Te_{4}$:Cd. However, the ($A^{o}$, X) emission in the photoluminescence spectrum of the $CdIn_{2}Te_{4}$:Te was the dominant intensity like in the as-grown $CdIn_{2}Te_{4}$ crystal. These results indicated that the ($D^{o}$, X) is associated with $V_{Te}$ which acted as donor and that the ($A^{o}$, X) emission is related to $V_{Cd}$ which acted as acceptor, respectively. The p-$CdIn_{2}Te_{4}$ crystal was obviously found to be converted into n-type after annealing in Cd atmosphere. The origin of ($D^{o},{\;}A^{o}$) emission and its to phonon replicas is related to the interaction between donors such as $V_{Te}$ or $Cd_{int}$, and acceptors such as $V_{Cd}$ or $Te_{int}$. Also, the In in the $CdIn_{2}Te_{4}$ was confirmed not to form the native defects because it existed in a stable bonding form.

• Journal of Radiation Protection and Research
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• 제49권2호
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• pp.85-90
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• 2024

Background: This study focuses on the fabrication and characterization of quasi-hemispherical Cd_0.9Zn_0.1Te (CZT) detector for gamma-ray spectroscopy applications, aiming to contribute to advancements in radiation measurement and research. Materials and Methods: A CZT ingot was grown using the vertical Bridgman technique, followed by proper fabrication processes including wafering, polishing, chemical etching, electrode deposition, and passivation. Response properties were evaluated under various external bias voltages using gamma-ray sources such as Co-57, Ba-133, and Cs-137. Results and Discussion: The fabricated quasi-hemispherical CZT detector demonstrated sufficient response properties across a wide range of gamma-ray energies, with sufficient energy resolution and peak distinguishability. Higher external bias voltages led to improved performance in terms of energy resolution and peak shape. However, further improvements in defect properties are necessary to enhance detector performance under low bias conditions. Conclusion: This study underscores the efficacy of quasi-hemispherical CZT detector for gamma-ray spectroscopy, providing valuable insights for enhancing their capabilities in radiation research field.

• 한국결정학회지
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• 제7권1호
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• pp.44-56
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• 1996

CuInTe2 다결정은 수평전기로에서 합성하고, CuInTe2 단결정은 수직 Bridgman 방법으로 성장하여 결정구조를 조사하고, Hall 효과를 30K에서 293K의 온도영역에서 측정하였다. CuInTe2 다결정 및 단결정은 정방정계였다. 다결정의 격자상수는 a=6.168Å, c=12.499Å 그리고 c/a=2.026이었고, 단결정의 격자상수는 a=6.186Å, c=12.453Å, 그리고 c/a=2.013이었다. CuInTe2 단결정의 성장면은 Laue 배면반사 사진으로부터 구하였으며 (112)면이었다. CuInTe2 단결정의 Hall 효과는 van der Pauw 방법으로 측정하였다. 상온에서 측정된 c축에 수직한 시료의 운반자농도 p는 2.14×1023holes/m3, 전기전도도 δ는 739.58Ω-1m-1 그리고 이동도 μ는 2.16×10 m2/V·s 이었다. c축에 평행한 시료의 운반자농도 p는 1.51×1023holes/m3, 전기전도도 σ는 717.55Ω-1m-1 그리고 이동도 μ는 2.97×10-2 m2/V·s이었다. c축에 수직 및 평행한 시료의 Hall계수가 양의 값이어서 CuInTe2 단결정은 p형 반도체임을 알 수 있었다.

• 한국결정학회지
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• 제8권1호
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• pp.48-58
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• 1997

[ $CuInTe_2$ ] 다결정은 수평전기로에서 합성하고, $CuInTe_2$ 단결정은 수직 Bridgman 방법으로 성장시켰다. $CuInTe_2$ 단결정의 c축에 수직 및 평행한 시료의 광전도도와 광발광특성을 293K에서 20 K의 온도영역에서 측정하였다. 측정된 광전류 봉우리로부터 구한 c축에 수직 및 평행한 시료의 에너지 띠 간격은 상온에서 각각 0.948 eV와 0.952 eV였다. 광전류 봉우리와 광발광 봉우리의 에너지차는 포논에너지이며 상온에서 c축에 수직 및 평행한 시료의 에너지차는 각각 22.12 meV와 21.4 meV였다. 또한 광전류 스펙트럼으로부터 시료의 spin-orbit 상호작용과 결정장 상호작용에 의한 가전자대의 갈라짐 ${\Delta}cr$과 ${\Delta}so$는 각각 0.046, 0.014 eV였다.