• Transactions on Electrical and Electronic Materials
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• v.12 no.4
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• pp.140-143
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• 2011

The growth and characterization of $In_{0.5}Ga_{0.5}As/In_{0.5}Al_{0.5}As$ narrow-gap inverted high electron mobility transistor structures, developed as a candidate material for spin-injection devices, are presented in this study. We have grown samples possessing surface $In_{0.5}Ga_{0.5}As$ channels of different thicknesses (30 nm and 60 nm) both with and without a thin 3 nm $In_{0.5}Ga_{0.5}As$ cap layer by using molecular beam epitaxy. We then investigated the in-plane transport properties as well as the Rashba spin-orbit coupling constant of the two-dimensional electron gas confined at the heterojunction interface.

• ETRI Journal
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• v.26 no.5
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• pp.475-480
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• 2004

Self-assembled InAs quantum dots (QDs) embedded in an InAlGaAs matrix were grown on an InP (001) using a solid-source molecular beam epitaxy and investigated using transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. TEM images indicated that the QD formation was strongly dependent on the growth behaviors of group III elements during the deposition of InAlGaAs barriers. We achieved a lasing operation of around 1.5 ${\mu}m$ at room temperature from uncoated QD lasers based on the InAlGaAs-InAlAs material system on the InP (001). The lasing wavelengths of the ridge-waveguide QD lasers were also dependent upon the cavity lengths due mainly to the gain required for the lasing operation.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.146-147
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• 2002

III-V magnetic semiconductors initiated by GaMnAs growth at low temperatures via molecular beam epitaxy (MBE) has been a hot issue recently for their possible application to spntronics. GaMnN may be one of the candidates for room temperature operating ferromagnetic semiconductors as proposed by a theoretical calculation, However, since GaN was grown at very high temperatures above ∼750$^{\circ}C$ even with MBE, it is expected that the incorporation of Mn into GaN will be limited. (omitted)

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.09a
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• pp.3-7
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• 1998

The rare-earth ions (R3+, R=Nd, Er) doped CaF2 layers have been grown on CaF2(111) substrate by molecular beam epitaxy. The epitaxial relationship and the crystallinity of CaF2:R3+ layers depending on the concentration of R3+ were studied by reflection high-energy electron diffraction (RHEED). In aspect of application as buffer layer in semiconductor-related hybrid structure, the lattice displacement between CaF2:R3+ layers and CaF2(111) substrate was investigated by X-ray rocking curve analysis.

• Proceedings of the Korean Magnestics Society Conference
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• 2005.12a
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• pp.62-62
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• 2005

• Proceedings of the Korean Vacuum Society Conference
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• 2007.08a
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• pp.269-269
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• 2007

• Proceedings of the Korean Vacuum Society Conference
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• 2006.08a
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• pp.162-162
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• 2006

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.161-162
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• 2007

(1-102) R-면 사파이어 기판 위에 플라즈마 분자선 에피탁시 법으로 성장시킨 비극성 ZnO 박막의 표면 형상을 원자력간현미경(AFM) 및 투과전자현미경으로 분석하였다. AFM 관찰 결과 ZnO<0001> 방향으로 길쭉한 제방 모양의 표면 형상이 나타남을 알 수 있었고, 고분해능 투과전자현미경 관찰을 통해 박막 성장 중에 관찰되는 V(chevron 모양) 형상의 in-situ RHEED 패턴을 야기시키는 박막 표면의 facet 면을 원자 level에서 확인하였다.

• Electronic Materials Letters
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• v.14 no.6
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• pp.784-792
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• 2018

In this letter, a standard deviation based optimization technique has been applied on High Resolution X-ray Diffraction symmetric and asymmetric scan results to accurately determine the Aluminum molar fraction and lattice relaxation of Molecular Beam Epitaxy grown compositionally graded Aluminum Gallium Nitride (AlGaN)/Aluminum Nitride/Gallium Nitride (GaN) heterostructures. Mathews-Blakeslee critical thickness model has been applied in an alternative way to determine the partially relaxed AlGaN epilayer thicknesses. The coupling coefficient determination has been presented in a different perspective involving sample tilt method by off set between the asymmetric planes of GaN and AlGaN. Sample tilt is further increased to determine mosaic tilt ranging between $0.01^{\circ}$ and $0.1^{\circ}$.

• Journal of Magnetics
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• v.10 no.3
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• pp.103-107
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• 2005

Magnetotransport is a prerequisite to realization of electronic operation of spintronic devices and it would be more useful if realized at room temperature. The effects of Be codoping on GaMnAs on magnetotransport were investigated. Mn flux was varied for growth of precipitated GaMnAs layers under a Be flux for degenerate doping via low-temperature molecular beam epitaxy. Magnetotransport as well as ferromagnetism at room temperature were realized in the precipitated GaAs:(Mn,Be) layers. Codoping of Be was shown to promote formation of MnGa clusters, and annealing process further stabilized the cluster phases. The room-temperature magnetic properties of the layers originate from the ferromagnetic clusters of MnGa and MnAs embedded in GaAs. The degenerately doped metallic GaAs matrix allowed the visualization of the magnetotransport through anomalous Hall effect.