• 한국재료학회지
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• 제32권3호
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• pp.132-138
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• 2022

Zintl phase Mg₃Sb₂ is a promising thermoelectric material in medium to high temperature range due to its low band gap energy and characteristic electron-crystal phonon-glass behavior. P-type Mg₃Sb₂ has conventionally exhibited lower thermoelectric properties compared to its n-type counterparts, which have poor electrical conductivity. To address these problems, a small amount of Sn doping was considered in this alloy system. P-type Mg₃Sb₂ was synthesized by controlled melting, pulverizing, and subsequent vacuum hot pressing (VHP) method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate phases and microstructure development during the process. Single phase Mg₃Sb₂ was successfully formed when 16 at.% of Mg was excessively added to the system. Nominal compositions of Mg_3.8Sb_2-xSn_x (0 ≤ x ≤ 0.008) were considered in this study. Thermoelectric properties were evaluated in terms of Seebeck coefficient, electrical conductivity, and thermal conductivity. A peak ZT value ≈ 0.32 was found for the specimen Mg_3.8Sb_1.994Sn_0.006 at 873 K, showing an improved ZT value compared to intrinsic one. Transport properties were also evaluated and discussed.

• 전기화학회지
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• 제8권3호
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• pp.135-138
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• 2005

본 연구에서는 구연산 수용액 전해질을 제조하여 전기도금 방식에 의해 III-V족 화합물 반도체 InSb를 전기화학적으로 합성하였다. 본 연구에서 제조된 InSb는 기존문헌에서 보고된 바와 달리 EPMA분석결과 In과 Sb의 조성비가 52:48로 화학양론을 정확하게 만족시키고 있고, XPS분석결과 전해질내의 구연산의 농도가 1.2M, pH가 4일 때 444.1 eV에서 InSb 화합물의 피크를 관찰하였으며 구연산의 농도가 1.2M보다 낮거나 pH가 4보다 낮을 때는 InSb화합물과 금속상태의 In이 혼재되어 있는 것을 확인하였다. 또한 XRD를 통하여 InSb(111)의 우선결정방위를 갖는다는 것을 확인하였고, I-V 특성 곡선 측정을 통해 rnSb가 고유한 반도체 특성을 보임을 확인하였다.

• 대한금속재료학회지
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• 제48권4호
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• pp.353-356
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• 2010

InSb thin films with a thickness of approximately 300 nm were prepared using single- and double-source vacuum evaporation methods and their structures and properties were investigated in terms of a heat treatment procedure. The double-source InSb films, prepared by the alternate stacking of In and Sb, were polycrystalline in structure and included small amounts of unreacted In and Sb phases. After annealing at elevated temperatures below the melting point of InSb (525$^{\circ}C$), the films changed into the InSb phase and were found to contain small amounts of unreacted In. The formation capability of the InSb compound was slightly lower for multilayer films than for single-layer films. The electrical and galvanomagnetic properties were found to be strongly related to the microstructures of the films. The maximum value of the Hall mobility and the magnetoresistance were determined to be $4.3{\times}10^3cm^2$/Vs and 70%, respectively, for the single-layer films, while these values for the alternately stacked films were respectively $2.9{\times}10^3cm^2$/Vs and 29% for the $[Sb(2.5)/In(2.5)]_{60}$ films, and $3.1{\times}10^3cm^2$/Vs and 10% for the $[Sb(150)/In(150)]_1$ films.

• 한국결정성장학회지
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• 제24권4호
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• pp.176-182
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• 2014

상온 압축 성형 후 고상 반응 소결 공정을 통하여 $Mg_3Sb_2$ 소결체를 제조하고자 하였다. Mg과 Sb의 성분의 몰비와 반응온도에 따른 결정상의 변화를 조사하였다. 773~843 K에서 얻어진 고상반응 소결체들은 전형적인 $Mg_3Sb_2$ 결정상을 형성하였으나 소결체의 위치에 따라 약간 다른 상적 구성을 보였다. 소결체 하단 부위에서 전형적으로 얻어지는 결정상이 얻어졌으며 823 K 온도에서는 Mg : Sb = 3.15 : 1.85 조성일 때, 843 K 온도에서는 Mg의 몰 수가 3.10 이상인 모든 조성에서 ${\alpha}-Mg_3Sb_2$ 상과 정확히 일치하는 결정상이 얻어졌다. 미량 남아있는 Mg 성분은 응고 후 냉각 시 ${\alpha}-Mg_3Sb_2$ 상으로부터 석출된 것으로 보인다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2000년도 추계학술발표강연 및 논문개요집
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• pp.145-145
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• 2000

• 한국재료학회지
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• 제3권6호
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• pp.678-683
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• 1993

MBE법으로 $580^{\circ}C$에서 성장한 $GaAs_{0.5}Sb_{0.5}$/(001)GaAs 에피층의 원자 배열을 TEM을 이용하여 분석하였다. 1/2(111) 형의 장범위 규칙상이 $GaAs_{0.5}Sb_{0.5}$/(001)GaAs 에피층에서 발견되었다. 이 규칙상의 원자 배열은 As의 농도가 높은 {111}As 면과 Sb의 농도가 높은 {l1l}Sb 면이 V족 소격자에 교대로 나열된 구조이며, 주기는 {111} 면간 거리의 2배이다. 이 구조는 R3m 의 공간군에 속하며, 단위포는 능면체정이다.

• 한국주조공학회지
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• 제32권2호
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• pp.91-97
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• 2012

The effects of Bi and Sb additions on the microstructures and casting properties in lead-free Cu-Zn-Sn broze were investigated. (1) When only Bi was added to the bronze, Bi was precipitated on the ${\delta}$ phase of ${\alpha}$ dendrite cell boundary. When Bi and Sb were added together, Bi was precipitated on the ${\delta}_A$ which was the Sb-rich area in the ${\delta}$ phase. (2) The addition of Sb accelerated the formation of ${\delta}$ phase, and when Sb, Bi and Pb were added, Bi and Pb were precipitated as mixed solution in the ${\delta}_A$ phase. (3) The combined addition of Sb and Bi resulted in the suppression of shrinkage due to the complementary effects of the mass feeding of ${\alpha}$-dendrite cluster covered with ${\delta}$ phase and sealing of micro-shrinkage in the ${\delta}$ phase by solidification expansion of Bi.

• 한국전기전자재료학회논문지
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• 제30권2호
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• pp.86-90
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• 2017

This work reports the phase-change behavior and thermal stability of doped GeSbTe/GeSbTe bilayers. We prepared the bilayers using RF sputtering, and annealed them at annealing temperature ranging from $100^{\circ}C$ to $400^{\circ}C$. The sheet resistance of the bilayer decreased and saturated with increasing annealing temperature, and the saturated value was close to that of pure GeSbTe film. The surface of the bilayer roughened at $400^{\circ}C$, which corresponds to the surface roughening of doped GeSbTe film. Mixed phases of face-centered cubic and hexagonal close-packed crystalline structures were identified in the bilayers annealed at elevated temperature. These results indicate that the phase-change behavior of the bilayer depends on the concurrent phase-transitions of the two GeSbTe-based films. The dopants in the doped GeSbTe film were diffused out at annealing temperatures of $300^{\circ}C$ or higher, which implies that the thermal stability of the bilayer should be considered for its application in phase-change electronic devices.

• 한국농공학회논문집
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• 제54권5호
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• pp.155-160
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• 2012

In this paper it was analyzed that the mechanical properties, the permeability and the freezing properties of SB-2 materials which are mainly used with the subbase materials. To this ends, a series of the physical test, the permeability test and the freezing test were carried out the samples mixed the small aggregate and the big aggregate from which was re-classified the SB-2. From the test results, it was analyzed the characteristics of permeability and the characteristics of freezing of the samples. And it was reviewed for SB-2 materials that the use of possibility for the freezing prevention layer material.

• 한국분말재료학회지
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• 제12권6호
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• pp.387-392
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• 2005

The p-type semiconductor $Bi_2Te_3-Sb_2Te_3$ thermoelectric materials were fabricated by melting, milling and sintering process and their thermoelectric properties were characterized. The compound materials were ball-milled with milling time and the powders were sintered by spark plasma sintering process. The ball milled powders had equiaxial shape and approedmately $1\~3{\mu}m$ in size. The figure of meritz of sintered thermoelectric materials decreased with milling time because of lowered electrical resistivity. The thermoelectric properties of $Bi_2Te_3-Sb_2Te_3$ materials have been discussed in terms of electrical property with ball mill process.