Chirped GaAs-AlAs distributed Bragg reflectors for high brightness yellow-green light-emitting diodes

Chang, Shoou Jinn; Chang, C. S.; Su, Yan–Kuin; Chang, P.T.; Wu, Yu Rue; Huang, Ke; Chen, T.P.

doi:10.1109/68.553084

Cited by 37 publications

(11 citation statements)

References 8 publications

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“…The methodology outlined in previous sections was applied to a model problem: a layered heterostructure consisting of alternating layers of gallium arsenide (GaAs) and aluminum arsenide (AlAs) deposited using MOVPE. Such a device could prove useful in Bragg reflectors, 39 because GaAs and AlAs are nearly lattice-matched, resulting in few defects, yet have significantly different refractive indices and bandgap energies. For industrial production, the percentage of functional devices can be increased by minimizing the thickness nonuniformity and the interfacial roughness between layers.…”

Section: Application To Gallium Arsenide/aluminum Arsenide Depositionmentioning

confidence: 99%

Optimal Design and Operation of a Spatially Distributed Multiscale Process, with Regard to Layered Heterostructure Growth

Behrens

Armaou

2010

Ind. Eng. Chem. Res.

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Determining the optimal operation of processes modeled by multiscale systems presents many challenges, because of complexities in modeling and the extensive computational requirements needed to solve them. Application to layered heterostructure deposition is considered here, where an additional challenge of interface characterization is encountered. A solution methodology is applied to the fabrication of a device consisting of alternating layers of gallium arsenide and aluminum arsenide, with the intent of minimizing thickness nonuniformity and interfacial step density. Using a finite-element solver and kinetic Monte Carlo simulations, we were able to balance reductions in thickness nonuniformity and interfacial step density with maintaining favorable operating conditions in a computationally efficient manner.

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Section: Application To Gallium Arsenide/aluminum Arsenide Depositionmentioning

confidence: 99%

Optimal Design and Operation of a Spatially Distributed Multiscale Process, with Regard to Layered Heterostructure Growth

Behrens

Armaou

2010

Ind. Eng. Chem. Res.

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“…For AlGaInP-based LEDs, it has been shown that one can use the tandem Bragg reflector structure and/or chirped DBR (CDBR) structure to achieve a wider reflection band [8]- [10]. It has also been shown that these two methods could both effectively enhance output intensity of the AlGaInP-based LEDs.…”

Section: Introductionmentioning

confidence: 96%

Design and Fabrication of a TiO<sub>2</sub>/SiO<sub>2</sub> Dielectric Broadband and Wide-Angle Reflector and Its Application to GaN-Based Blue LEDs

Lin

Shei

Chang

2015

IEEE J. Quantum Electron.

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In this paper, optical software and ion-assisted e-gun evaporation with radio frequency neutralizer were applied to simulate and fabricate a broadband reflector, respectively. It can almost reach 100% between 400 and 630 nm and between 400 and 580 nm with light incident angles of 5°and 45°, respectively. With 350-mA current injection, it was found that we achieved 34% enhancement in the GaN-based blue LEDs output power by the formation of a broadband reflector. Furthermore, it can be seen clearly that the optical microscopes images of the LEDs with an 11 pairs distrbuted Bragg reflector and with a broadband reflector were brighter than that of the LED without a reflector. The LED with a broadband reflector is the brightest of all LEDs. This result agrees with that observed in the current-output power characteristics.

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“…[9] To improve the LEE of AlGaInP LED, several efficient methods of reducing the substrate absorption have been proposed. [10][11][12][13][14][15][16][17][18][19][20] A distributed Bragg reflector (DBR) structure of repeated periodically (Al x Ga 1−x )As/(Al y Ga 1−y )As stacks [10,11] enhances the light output by back reflection, but the reflectivity is quite sensitive to the angle and wavelength of emission. The reformative DBR structure consisting of coupled DBR, tandem DBR or hybrid-type DBR [12][13][14] and the omnidirectional reflector (ODR) structure [15][16][17] can exhibit a broader reflective bandwidth and less dependence on the incident angle.…”

Section: Introductionmentioning

confidence: 99%

Characteristic improvements of thin film AlGaInP red light emitting diodes on a metallic substrate

Zhao¹,

Hu²,

Tang³

et al. 2018

Chinese Phys. B

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We report a type of thin film AlGaInP red light emitting diode (RLED) on a metallic substrate by electroplating copper (Cu) to eliminate the absorption of GaAs grown substrate. The fabrication of the thin film RLED is presented in detail. Almost no degradations of epilayers properties are observed after this substrate transferred process. Photoluminescence and electroluminescence are measured to investigate the luminous characteristics. The thin film RLED shows a significant enhancement of light output power (LOP) by improving the injection efficiency and light extraction efficiency compared with the reference RLED on the GaAs parent substrate. The LOPs are specifically enhanced by 73.5% and 142% at typical injections of 2 A/cm 2 and 35 A/cm 2 respectively from electroluminescence. Moreover, reduced forward voltages, stable peak wavelengths and full widths at half maximum are obtained with the injected current increasing. These characteristic improvements are due to the Cu substrate with great current spreading and the back reflection by bottom electrodes. The substrate transferred technology based on electroplating provides an optional way to prepare high-performance optoelectronic devices, especially for thin film types.

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Chirped GaAs-AlAs distributed Bragg reflectors for high brightness yellow-green light-emitting diodes

Cited by 37 publications

References 8 publications

Optimal Design and Operation of a Spatially Distributed Multiscale Process, with Regard to Layered Heterostructure Growth

Optimal Design and Operation of a Spatially Distributed Multiscale Process, with Regard to Layered Heterostructure Growth

Design and Fabrication of a TiO<sub>2</sub>/SiO<sub>2</sub> Dielectric Broadband and Wide-Angle Reflector and Its Application to GaN-Based Blue LEDs

Characteristic improvements of thin film AlGaInP red light emitting diodes on a metallic substrate

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