• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.251-254
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• 2012

본 논문에서는 양자 우물 구조 변화에 따른 GaN 기반 LED의 출력 특성을 분석하였다. 사용된 LED의 기본 구조는 GaN 버퍼층을 기반으로 GaN 장벽과 InGaN 양자 우물로 이루어진 활성 영역이 AlGaN EBL(Electron Blocking Layer)과 AlGaN HBL(Hole Blocking Layer) 사이에 구성되어 있다. ISE-TCAD를 이용하여 LED 활성영역의 양자 우물의 두께와 개수, 장벽의 도핑 변화에 따른 출력 전력, 내부 양자 효율 특성을 분석하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 춘계학술발표대회 및 제12회 신소재 심포지엄
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• pp.21.2-21.2
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• 2007

• 마이크로전자및패키징학회지
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• 제25권3호
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• pp.1-5
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• 2018

본 연구에서는 InGaN/GaN multi quantum well (MQW)에서 Indium (In) 도핑효과에 따른 광전기화학적 특성을 관찰하였다. 기판으로는 Sapphire을 사용하였고, 각 Quantum well (QW)을 구성하고 있는 InGaN의 조성을 다르게 하였다. 투과도 측정 결과 일정한 In 조성을 가진 InGaN/GaN MQW에 비해 각 QW의 In 조성을 다르게 한 InGaN/GaN MQW에서 흡수도가 향상되는 것을 확인할 수 있었다. 이는 각각 다른 In 조성을 가진 InGaN 층이 더 넓은 영역의 스펙트럼 에너지를 가지는 빛을 흡수하기 때문인 것으로 생각된다. 광학적 특성을 평가하기 위해 진행한 상온 photoluminescence (PL) 실험을 진행한 결과, 역시 다양한 In 조성을 가진 InGaN/GaN MQW이 더 넓은 파장에서 발광이 나타나는 것을 확인할 수 있었다. 이들 샘플에 대한 광전기화학적 특성평가를 통하여, gradation In 조성을 가지고 있는 InGaN/GaN MQW이 일정한 In 조성을 가지는 InGaN/GaN MQW에 비해 광전기화학적 물분해 능력이 월등히 향상됨을 확인하였다.

• Applied Science and Convergence Technology
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• 제26권3호
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• pp.52-54
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• 2017

An InGaN/GaN multiple quantum well (MQW) structure is grown on a GaN/sapphire template using a plasma-assisted molecular beam epitaxy (PA-MBE). The fluctuation of the quantum well thickness formed from roughly-grown InGaN layer results in a disordered photoluminescence (PL) spectrum. The surface morphologies of the InGaN layers with various In compositions are investigated by reflection high energy electron diffraction (RHEED) and atomic force microscopy (AFM). A blurred InGaN/GaN hetero-interface and the non-uniform QW size is confirmed by high resolution transmission electron microscopy (HR-TEM). Inhomogeneity of the quantum confinement results in a degradation of the quantum efficiency even though the InGaN layer has a uniform In composition.

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 동계학술발표회 논문집
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• pp.509-510
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• 2009

The optical gain of InGaN/GaN multi quantum well (MQW) resonant-cavity light-emitting diode (RC-LED) with different Indium composition and well width in the multi-quantum well was investigated. The optimized optical gain was obtained by simulating active region InGaN/GaN with some test values of well width and Indium composition. By simulation tool, we could simulate on several cases, and then we got exact well width and Indium composition that makes optical gain maximum due to the short wavelength of 470 nm for blue light emission.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.52-54
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• 2008

The authors investigated the InGaN/GaN multi-quantum well blue light emitting diodes with the implements of the photonic crystals fabricated at the top surface of p-GaN layer or the bottom interface of n-GaN layer. The top photonic crystals result in the lattice-dependent photoluminescence spectra for the blue light emitting diodes, which have a wavelength of 450nm. However, the bottom photonic crystal shows a big shift of the photoluminescence peak from 444 nm to 504 nm and played as a role of quality enhancement for the crystal growth of GaN thin film. The micro-Raman spectroscopy shows the improved epitaxial quality of GaN thin film.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.686-689
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• 2012

본 논문에서는 ISE-TCAD를 이용하여 GaN 기반의 LED특성을 분석하였다. LED는 GaN 버퍼층을 기반으로 GaN 장벽과 InGaN 양자우물로 구성된 활성 영역, AlGaN EBL(Electron Blocking Layer)과 AlGaN HBL(Hole Blocking Layer)로 이루어져 있다. Auger 재결합률, 양자 우물의 폭과 수, EBL의 Al 몰분율의 변화에 따른 LED의 출력 전력 특성을 분석하고 효율 개선을 위한 몇 가지 기준을 제시하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.121-125
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• 2003

Time-resolved photoluminescence from InGaN/GaN multi-quantum well structures was investigated for two different shapes of square- and trapezoidal wells grown by metal-organic chemical vapor deposition. To compare to the conventional square well structure with a radiative recombination lifetime of 0.170 nsec, the large value of lifetime of 0.540 nsec from trapezoidal well were found at room temperature. This value is similar to the value for GaN host material indicating no confinement effect of quantum well. Furthermore, the high resolution transmission electron microscopy image provides the In clustering effect in the trapezoidal well structure.

• Transactions on Electrical and Electronic Materials
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• 제4권5호
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• pp.19-23
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• 2003

Time-resolved photoluminescence from InGaN/GaN multi-quantum well structures was investigated for two different shapes of square-and trapezoidal wells grown by metal-organic chemical vapor deposition. To compare to the conventional square well structure with a radiative recombination lifetime of 0.170 nsec, the large value of lifetime of 0.540 nsec from trapezoidal well were found at room temperature. This value is similar to the value for GaN host material indicating no confinement effect of quantum well. Furthermore, the high resolution transmission electron microscopy image provides the In clustering effect in the trapezoidal well structure.

• 반도체디스플레이기술학회지
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• 제20권3호
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• pp.167-171
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• 2021

The core-shell InGaN/GaN Multi Quantum Well-Nanowires (MQW-NWs) that were selectively grown on oxide templates with perfectly circular hole patterns were highly crystalline and were shaped as high-aspect-ratio pyramids with semi-polar facets, indicating hexagonal symmetry. The formation of the InGaN active layer was characterized at its various locations for two types of the substrates, one containing defect-free MQW-NWs with GQDs and the other containing MQW-NWs with defects by using HRTEM. The TEM of the defect-free NW showed a typical diode behavior, much larger than that of the NW with defects, resulting in stronger EL from the former device, which holds promise for the realization of high-performance nonpolar core-shell InGaN/GaN MQW-NW substrates. These results suggest that well-defined nonpolar InGaN/GaN MQW-NWs can be utilized for the realization of high-performance LEDs.