• 마이크로전자및패키징학회지
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• 제4권2호
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• pp.71-78
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• 1997

본 논문에서는 InGaAsP 에피막에서 도핑 농도와 에피막의 미세조직구조가 photoluminescence (PL) 스펙트럼의 위치 및 형상에 어떤 영향을 미치는가를 연구하였고, 그 결과를 설명하기 위해 가능한 모델을 제시하였다. InGaAsP 에피막(발진파장 ~1.3$\mu$m) 을 액상증착법(liquid phase epitaxy, LPE)으로 성장하여 9K에서 PL측정을 했을 때 InGaAsP 활성층 내 Zn 억셉터의 유무에 따라 PL 피크의 위치가 최대 30nm (24meV)까지 shift하고 피크의 선폭도 넓어지는 현사을 발견하였다. 이와같은 피크 분산현상은 inGaAsP 에피막이 유기금속 기상증착법으로 성장되거나 Zn로 고농도로 도핑되거나 고온에서 어닐링 될 경우 대폭 감소하였다. 이를 설명하기 위해 여러 가지 모델을 설정하여 실험을 하였으며 이 중 InGaAsP 에피막의 미세조직구조 특히 Spinodal 분해에 의한 조성이 모듈레이션과 Zn의 상호작용의 관계가 이 현상을 설명하는 데 가장 적절하다는 것을 밝혔다.

• 한국결정성장학회지
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• 제29권4호
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• pp.143-148
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• 2019

우리는 분자선 에피택시(Molecular Beam Epitaxy) 법을 사용하여 광전기화학적 물분해 수소생산용 고종횡비 GaN 기반 나노와이어를 Si 기판 위에 성공적으로 제작하였다. 주사전자현미경(SEM)과 에너지분산형 분광법(EDX)은 p-GaN:Mg 및 p-InGaN 나노와이어가 고밀도와 함께 수직으로 성장 되었음을 증명하였다. 또한, p-InGaN 나노와이어의 발광 파장을 552 nm에서 590 nm까지의 조절이 가능하다는 것을 확인하였다. 이렇게 제작된 p-InGaN 나노와이어는 태양광을 통해 외부 전위 없이 물분해가 가능한 수소생산용 광촉매로써 매우 유용하게 사용될 수 있다.

• ETRI Journal
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• 제11권4호
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• pp.84-97
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• 1989

The influence of Zn, Si and Te diffusion on the interdiffusion in $GaAs-Ga_1_-xIN_xAs_1__yP_y$and InP$Ga_1__xIn_xAs_1__yP_y$ heterostructures was studied. The heterostructures were grown by liquid phase epitaxy, and the impurity diffusion into the heterostructures was carried out using metal compound or element sources. The extent of interdiffusion for both group III and V atoms was observed by depth profiling of matrix elements with secondary ion mass spectrometry and Auger electron spectroscopy. Selective enhancement of cation interdiffusion was observed by the concurrent Zn diffusion in both the GaAs based-and InP based-crystals. In contrast to the Zn diffusion, the Si diffusion in the GaAs based-crystal and the Te diffusion in the InP based-crystal enhanced both cation and anion interdiffusion to the same extent. A kick-out mechanism is proposed to explain the selective enhancement of the cation interdiffusion due to Zn, and a single vacancy mechanism is proposed for the interdiffusion due to Si and Te.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.155-159
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• 2003

This paper presents fully integrated 5 GHz band low phase noise LC tank VCO. The implemented VCO is tuned by integrated PN diode and tuning rage is $5.01{\sim}5.30$ GHz under $0{\sim}3 V$ control voltage. For good phase noise performance, LC filtering technique, common in Si CMOS process, is used, and to prevent degradation of phase noise performance by collector shot-noise and to reduce power dissipation the HBT is biased at low collector current density bias point. The measured phase noise is -87.8 dBc/Hz at 100 kHz offset frequency and -111.4 dBc/Hz at 1 MHz offset frequency which is good performance. Moreover phase noise is improved by roughly 5 dEc by LC filter. It is the first experimental result in InGaP/GaAs HBT process. The figure of merit of the fabricated VCO with LC filter is -172.1 dBc/Hz. It is the best result among 5 GHz InGaP HBT VCOs. Moreover this work shows lower DC power consumption, higher output power and more fixed output power compared with previous 4, 5 GHz band InGaP HBT VCOs.

• 한국재료학회지
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• 제30권12호
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• pp.666-671
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• 2020

The electronic structure and magnetic properties of chalcopyrite (CH) AlGaAs2 with dopant Mn at 3.125 and 6.25 % concentrations are investigated using first-principles calculations. The CH AlGaAs2 alloy is a p-type semiconductor with a small band-gap. The AlGaAs2:Mn shows that the ferromagnetic (FM) state is the most energetically favorable one. The Mn-doped AlGaAs2 exhibits FM and strong half-metallic ground states.The spin polarized Al(Ga,Mn)As2 state (Al-rich system) is more stable than the (Al,Mn)GaAs2 state (Ga-rich system), which has a magnetic moment of 3.82mB/Mn. The interaction between Mn-3d and As-4p states at the Fermi level dominates the other states.The states at the Fermi level are mainlyAs-4p electrons, which mediate strong interaction between the Mn-3d and As-4p states. It is noticeable that the FM ordering of dopant Mn with high magnetic moment originates from the As(4p)-Mn(3d)-As(4p) hybridization, which is attributed to the partially unfilled As-4pbands. The high FM moment of Mn is due to the double-exchange mechanism mediated by valence-band holes.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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• pp.13-16
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• 2001

InP/InGaAs Heterojunction phototransistors(HPT's) with an optically transparent ITO emitter electrode were fabricated and characterized. At the same time, heterojuntion transistors(HBT's) having the same device layout were fabricated. By comparison with InP/InGaAs HBT's, the do characteristics of InP/InGaAs HPT's showed the similar electrical charateristics of HBT's. the model parameters of the device were extracted and compared.

• 한국레이저가공학회지
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• 제8권3호
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• pp.5-10
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• 2005

[ $InxGa_{1-x}P/GaAs$ ] structures were grown by chemical beam epitaxy(CBE), Pure phosphine($PH_3$) gases were used as group V sources. for the group III sources, TEGa, TmIn were used. $InxGa_{1-x}P$ epilayer was grown on SI-GaAs substrate and has a 1-${\mu}m$ thick. We have investigated the characteristics of $InxGa_{1-x}P$ by the photoreflectance(PR) spectroscopy, The PR spectrum of $InxGa_{1-x}P$ shows third-derivative feature whose Peaks Provide energy gap. The energy gap of $InxGa_{1-x}P$ has deduced composition x. From temperature dependance of PR spectra, temperature coefficient is $dEg/dT=-3.773{\times}10^{-4}$ eV/K, and Varshni coefficients $\alpha$ and $\beta$ values obtained $4{\times}10^4$ eV/K and 267 K respectively. Also, interaction $\alpha$B was 19.4 meV using the Bose-Einstein temperature relation, and $\Theta$ value related the average phonon frequency were 101.4 K. In particular, shoulder peak related to defects observed in PR signal that measured in temperature 82 K.

• E2M - 전기 전자와 첨단 소재
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• 제7권4호
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• pp.312-316
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• 1994

In this study, ln$_{1-x}$ Ga$_{x}$P alloy crystal which has different compositions were grown by the temperature gradient solution(TGS) method, and the properties of deep levels were measured in the temperature range of 9OK-450K. We find the four deep levels of E$_{1}$, E$_{2}$(248meV), E$_{3}$(386meV) and E$_{4}$(618meV) in GaP, which has composition of Ga in In$_{1-x}$ Ga$_{x}$P is one, and the trap densities of E$_{3}$ and E4 levels were 7.5*10$^{14}$ cm$^{-3}$ and 9*10$^{14}$ cm$^{-3}$ , respectively. A broad deep level spectra was revealed in In$_{1-x}$ Ga$_{x}$P whose composition of Ga, x, were 0.56 and 0.83, and the activation energy and trap densities were about 430meV and 6*10$^{14}$ cm$^{-3}$ , respectively.ectively.

• 한국진공학회지
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• 제15권3호
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• pp.294-300
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• 2006

금속유기화학증착기 (metal-organic chemical vapor deposition)를 이용하여 분포귀환형 (distributed feed back) InP/InGaAs/InP 회절격자 구조를 제작하고 원자력간현미경 (atomic force microscopy)과 주사전자현미경 (scanning electron microscopy) 실험을 통해 표면 및 단면을 분석하였다. 그 위에 분자선증착기(molecular beam epitaxy)법을 이용하여 자발형성 (self-assembled) InAs/InAlGaAs 양자점 (quantum dot)을 성장하고, 광학적 특성을 온도변화 광여기 발광 (photoluminescence)으로 회절격자 구조 없이 성장한 양자점 시료와 비교 분석하였다. 회절격자의 간격 대비 폭의 비가 약 30%인 InP/InGaAs/InP 회절격자가 제작되었으며, 그 위에 성장된 양자점의 경우 상온 파장이 1605 nm에서 PL이 관찰되었다. 이는 회절격자 없이 같은 조건에서 성장된 시료의 상온 파장인 1587 nm 보다 장파장에서 발광하였으며, 회절격자의 영향으로 양자점 크기가 변하였음을 조사하였다.

• Journal of the Optical Society of Korea
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• 제11권3호
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• pp.133-137
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• 2007

We compare electroabsorption modulators (EAMs) with multiple quantum wells (MQWs) based on InGaAs(P)/InP and InGa(Al)As/InAlAs material systems. We carefully choose the quantum-well structures so that the structures based on different material systems have similar band-offset energies and excition-peak wavelengths. Assuming the same light wavelength of $1.55{\mu}m$, we show the transfer functions of EAMs with each quantum-well structure and calculate the escape times of photogenerated charge carriers. As the heavy-hole escape time of the quantum well based on InGaAs(P)/InP is much longer than those of photogenerated charge carriers of InGa(Al)As/InAlAs, the EAM based on the InGa(Al)As/InAlAs material seems to be more suitable for high-optical-power operation.