Performance Analysis of GaN-Based Light-Emitting Diodes With Lattice-Matched InGaN/AlInN/InGaN Quantum-Well Barriers

Wang, Naiyin; Yin, Yi An; Zhao, Bin; Mei, Ting

doi:10.1109/jdt.2015.2444400

Cited by 5 publications

(8 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As the period of PC-structured p-GaN nanorods increases from 100 to 150 nm, the formation of couple mode and better control over the directionality of emission light make With considering the series resistivity, the forward voltage for InGaN/GaN LEDs can be expressed as follows [46] V F = V D + I D R s (6) where V F , V D , I D , and R s are forward voltage, diode voltage, forward current, and series resistance. The calculated V D for InGaN/GaN green LEDs without and with PC-structured p-GaN nanorods is around 3.06 and 3.04 V under driving current of 20 mA.…”

Section: Resultsmentioning

confidence: 99%

“…Many manuscripts have been reported on the design of active region, carrier confinement, and reduction of defects to improve the IQE of GaN-based LEDs. Introduction of the silicon-doped GaN quantum barrier with well-defined thickness in InGaN/GaN active region [ 4 ], deposition of short-period superlattices in multiple-quantum-wells (MQWs) [ 5 ] and fabrication of lattice-matched InGaN/AlInN/InGaN MQWs [ 6 ] enhance the IQE of GaN-based LEDs due to the alleviation of strain in an active region. Electron-blocking layer with high bandgap grown at the interface of MQWs and cladding layer confines the electrons in the active region to increase the probability of radiative recombination in the active region [ 7 ].…”

Section: Introductionmentioning

confidence: 99%

“…The series resistances for InGaN/GaN LEDs without and with PC-structured p-GaN nanorods of 100, 150, and 200 nm period (fixed height of 110 nm) are 16.7, 20.7, 21, and 20.3 Ω in Figure 6a and for InGaN/GaN LEDs with PC-structured p-GaN nanorods of 90, 110, and 130 nm height (fixed period of 150 nm) are 20.8, 21, and 20 Ω in Figure6b. With considering the series resistivity, the forward voltage for InGaN/GaN LEDs can be expressed as follows[46] V F = V D + I D R s(6)…”

mentioning

confidence: 99%

See 2 more Smart Citations

Investigation of Photonic-Crystal-Structured p-GaN Nanorods Fabricated by Polystyrene Nanosphere Lithography Method to Improve the Light Extraction Efficiency of InGaN/GaN Green Light-Emitting Diodes

2021

View full text Add to dashboard Cite

We fabricated the photonic-crystal-structured p-GaN (PC-structured p-GaN) nanorods using the modified polystyrene nanosphere (PS NS) lithography method for InGaN/GaN green light-emitting diodes (LEDs) to enhance the light extraction efficiency (LEE). A modified PS NS lithography method including two-times spin-coating processes and the post-spin-coating heating treatment was used to obtain a self-assembly close-packed PS NS array of monolayer as a mask and then a partially dry etching process was applied to PS NS, SiO2, and p-GaN to form PC-structured p-GaN nanorods on the InGaN/GaN green LEDs. The light output intensity and LEE of InGaN/GaN green LEDs with the PC-structured p-GaN nanorods depend on the period, diameter, and height of PC-structured p-GaN nanorods. RSoft FullWAVE software based on the three-dimension finite-difference time-domain (FDTD) algorithm was used to calculate the LEE of InGaN/GaN green LEDs with PC-structured p-GaN nanorods of the varied period, diameter, and height. The optimal period, diameter, and height of PC-structured p-GaN nanorods are 150, 350, and 110 nm. The InGaN/GaN green LEDs with optimal PC-structured p-GaN nanorods exhibit an enhancement of 41% of emission intensity under the driving current of 20 mA as compared to conventional LED.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Investigation of Photonic-Crystal-Structured p-GaN Nanorods Fabricated by Polystyrene Nanosphere Lithography Method to Improve the Light Extraction Efficiency of InGaN/GaN Green Light-Emitting Diodes

2021

View full text Add to dashboard Cite

show abstract

“…overlap [8], [9]. To address this issue, researchers have utilized various approaches, including nonpolar and semi-polar orientations [10]; and introduced Si doping in quantum barriers (QBs) to screen the internal polarization induced by the electric field [11]; and polarization-matched and lattice-matched MQWs have been designed [12], [13]. Besides, Shervin et al modified the piezoelectric polarization and significantly improved the LED efficiency by external bending [14].…”

Section: Introductionmentioning

confidence: 99%

Polarization Modulation at Last Quantum Barrier for High Efficiency AlGaN-Based UV LED

Liu

Wang

et al. 2022

IEEE Photonics J.

View full text Add to dashboard Cite

The performance of AlGaN-based light-emitting diodes (LEDs) emitting at UVA-UVC regions can be severely compromised due to the polarization difference (∆P) between the last quantum barrier (LQB) and the electron blocking layer (EBL). In this work, the different situations of the bandgap difference (∆Eg) and ∆P of InAlN/AlGaN and AlGaN/AlGaN heterojunctions fully strained on GaN and AlN substrates are discussed. It shows that the InAlN/AlGaN heterojunctions could produce positive or negative sheet charges at the heterointerface under ∆Eg >0, which could not be realized by the conventional AlGaN/AlGaN heterojunctions. To demonstrate and utilize the feature, the polarization-modulated InAlN LQBs with 0.14-0.16 indium compositions of 320 nm UVB LEDs are designed and investigated. It is observed that the InAlN LQBs could replace the conventional AlGaN LQB to improve electron confinement and hole injection by affecting effective barrier heights. By modulating the LQB/EBL polarization using InAlN, the proposed UV LED has a 32% enhancement in internal quantum efficiency and lower efficiency droop (from 16.9% to 0.7%) compared with the conventional one without modulation. The operation voltage at the same current also significantly decreases. The improvement of optical output power and wall plug efficiency at 60 mA in proposed structures are near 90% and 100%, respectively. This study provides a novel and highly effective methodology for development of high efficiency UV LEDs.

show abstract

“…In this regard, different EBL-free LED designs have been studied for III-nitride semiconductor LEDs. Linear graded quantum barrier (QB)-based EBL-free AlGaN UV LEDs with similar optical performance compared to conventional EBL LEDs [ 12 ], strip-in-a-barrier AlGaN UV LEDs without EBL with remarkably high performance compared to regular EBL LEDs [ 13 ], band engineered EBL-free AlInN UV LEDs [ 14 ], lattice-matched InGaN/AlInN/InGaN QB visible LEDs without EBL [ 15 ], EBL-free coupled quantum wells (QWs) based InGaN/GaN nanowire LED for white light emission [ 16 ] are some of the reported studies. However, to-date, a study on high-performance EBL free AlGaN deep UV LEDs is limited.…”

Section: Introductionmentioning

confidence: 99%

Improved Performance of Electron Blocking Layer Free AlGaN Deep Ultraviolet Light-Emitting Diodes Using Graded Staircase Barriers

et al. 2021

View full text Add to dashboard Cite

To prevent electron leakage in deep ultraviolet (UV) AlGaN light-emitting diodes (LEDs), Al-rich p-type AlxGa(1−x)N electron blocking layer (EBL) has been utilized. However, the conventional EBL can mitigate the electron overflow only up to some extent and adversely, holes are depleted in the EBL due to the formation of positive sheet polarization charges at the heterointerface of the last quantum barrier (QB)/EBL. Subsequently, the hole injection efficiency of the LED is severely limited. In this regard, we propose an EBL-free AlGaN deep UV LED structure using graded staircase quantum barriers (GSQBs) instead of conventional QBs without affecting the hole injection efficiency. The reported structure exhibits significantly reduced thermal velocity and mean free path of electrons in the active region, thus greatly confines the electrons over there and tremendously decreases the electron leakage into the p-region. Moreover, such specially designed QBs reduce the quantum-confined Stark effect in the active region, thereby improves the electron and hole wavefunctions overlap. As a result, both the internal quantum efficiency and output power of the GSQB structure are ~2.13 times higher than the conventional structure at 60 mA. Importantly, our proposed structure exhibits only ~20.68% efficiency droop during 0–60 mA injection current, which is significantly lower compared to the regular structure.

show abstract

Performance Analysis of GaN-Based Light-Emitting Diodes With Lattice-Matched InGaN/AlInN/InGaN Quantum-Well Barriers

Cited by 5 publications

References 38 publications

Investigation of Photonic-Crystal-Structured p-GaN Nanorods Fabricated by Polystyrene Nanosphere Lithography Method to Improve the Light Extraction Efficiency of InGaN/GaN Green Light-Emitting Diodes

Investigation of Photonic-Crystal-Structured p-GaN Nanorods Fabricated by Polystyrene Nanosphere Lithography Method to Improve the Light Extraction Efficiency of InGaN/GaN Green Light-Emitting Diodes

Polarization Modulation at Last Quantum Barrier for High Efficiency AlGaN-Based UV LED

Improved Performance of Electron Blocking Layer Free AlGaN Deep Ultraviolet Light-Emitting Diodes Using Graded Staircase Barriers

Contact Info

Product

Resources

About