Buried Tunnel Contact Junctions in GaN-Based Light-Emitting Diodes

Jeon, Sohee; Song, Yun Heub; Jang, Hyun Jin; Kim, K.S.; Yang, Gye Mo; Hwang, Sungwoo

doi:10.1002/1521-396x(200111)188:1<167::aid-pssa167>3.0.co;2-d

Cited by 10 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…21 For this purpose, the p þ /n þ tunnel junction has previously been proposed to enhance the lateral current distribution in InGaN/GaN LEDs. [22][23][24][25][26] In these devices, the heavy doping in GaN layers induces a strong built-in electric field, which aligns the conduction band of the n þ -GaN layer with the valence band of the p þ -GaN layer. 27 However, this tunnel region is a homojunction with no polarization induced electric fields and yields a low level of tunneling efficiency.…”

mentioning

confidence: 99%

InGaN/GaN light-emitting diode with a polarization tunnel junction

Zhang

Tan

Kyaw

et al. 2013

Applied Physics Letters

103

View full text Add to dashboard Cite

Cataloged from PDF version of article.We report InGaN/GaN light-emitting diodes (LED) comprising in situ integrated p(+)-GaN/InGaN/n(+)-GaN polarization tunnel junctions. Improved current spreading and carrier tunneling probability were obtained in the proposed device architecture, leading to the enhanced optical output power and external quantum efficiency. Compared to the reference InGaN/GaN LEDs using the conventional p(+)/n(+) tunnel junction, these devices having the polarization tunnel junction show a reduced forward bias, which is attributed to the polarization induced electric fields resulting from the in-plane biaxial compressive strain in the thin InGaN layer sandwiched between the p(+)-GaN and n(+)-GaN layers. (C) 2013 AIP Publishing LLC

show abstract

mentioning

confidence: 99%

InGaN/GaN light-emitting diode with a polarization tunnel junction

Zhang

Tan

Kyaw

et al. 2013

Applied Physics Letters

103

View full text Add to dashboard Cite

show abstract

“…As mentioned, another approach to improve the current spreading is to reduce the R TCL . Therefore, the n + ‐GaN/p + ‐GaN tunnel junction is demonstrated to improve the current spreading . However, the carrier interband tunneling process requires a strong electric field in the tunnel junction, which is merely determined by the doping concentration in the n + ‐GaN/p + ‐GaN junction.…”

Section: Approaches For Improving the Internal Quantum Efficiencymentioning

confidence: 99%

On the internal quantum efficiency for InGaN/GaN light-emitting diodes grown on insulating substrates

Zhang

et al. 2016

Phys. Status Solidi A

View full text Add to dashboard Cite

The internal quantum efficiency (IQE) for InGaN/GaN light‐emitting diodes (LEDs) grown on [0001] sapphire substrates is strongly affected by various factors including polarization effect in the InGaN/GaN multiple quantum wells (MQWs), insufficient electron and hole injections, low p‐type GaN doping efficiency, carrier loss due to the Auger recombination, and current crowding effect especially for the hole current in the p‐GaN region. In this work, the remedies taken by the scientific community to enhance the IQE are reviewed, compared and summarized. Meanwhile, this review also discusses alternative ways including polarization self‐screening effect, polarization cooling, hole accelerator, and hole modulator. The structural solutions we propose in this work can better improve the device performance without increasing the processing difficulty significantly, and their effectiveness in improving the IQE is further supported by the numerical and experimental studies. For example, on the contrary to common belief, the polarizations in the [0001] oriented InGaN/GaN LEDs can be advantageously used to improve the device performance based on our designs.

show abstract

“…However, there will be more difficulties and challenges in fabricating the vertical LEDs. In order to improve the current spreading and suppress the current crowding effect, some approaches, such as improving the design of the hole injection layer [27], optimization of the mesa area size to adjust the current distribution [28], enhancing the conductivity of the contact layer with the p-electrode [27], transparent p-side electrode fabrication [7,29], and use of a tunnel junction (TJ) or a polarization TJ (PTJ) [30][31][32][33][34][35][36][37][38][39][40][41] have been proposed.…”

Section: Introductionmentioning

confidence: 99%

“…In 2001, an InGaN-based blue LED with a p + -GaN/n + -GaN TJ was reported, with an optical output power about twice that of conventional LEDs without a TJ [32]. However, the forward voltage of the LED was accordingly increased from 3.9 to 4.9 V, which was caused by the relatively high resistance in TJ.…”

Section: Introductionmentioning

confidence: 99%

Calculating the Effect of AlGaN Dielectric Layers in a Polarization Tunnel Junction on the Performance of AlGaN-Based Deep-Ultraviolet Light-Emitting Diodes

et al. 2021

View full text Add to dashboard Cite

In this work, AlGaN-based deep-ultraviolet (DUV) light-emitting diodes (LEDs) with AlGaN as the dielectric layers in p+-Al0.55Ga0.45N/AlGaN/n+-Al0.55Ga0.45N polarization tunnel junctions (PTJs) were modeled to promote carrier tunneling, suppress current crowding, avoid optical absorption, and further enhance the performance of LEDs. AlGaN with different Al contents in PTJs were optimized by APSYS software to investigate the effect of a polarization-induced electric field (Ep) on hole tunneling in the PTJ. The results indicated that Al0.7Ga0.3N as a dielectric layer can realize a higher hole concentration and a higher radiative recombination rate in Multiple Quantum Wells (MQWs) than Al0.4Ga0.6N as the dielectric layer. In addition, Al0.7Ga0.3N as the dielectric layer has relatively high resistance, which can increase lateral current spreading and enhance the uniformity of the top emitting light of LEDs. However, the relatively high resistance of Al0.7Ga0.3N as the dielectric layer resulted in an increase in the forward voltage, so much higher biased voltage was required to enhance the hole tunneling efficiency of PTJ. Through the adoption of PTJs with Al0.7Ga0.3N as the dielectric layers, enhanced internal quantum efficiency (IQE) and optical output power will be possible.

show abstract

Buried Tunnel Contact Junctions in GaN-Based Light-Emitting Diodes

Cited by 10 publications

References 8 publications

InGaN/GaN light-emitting diode with a polarization tunnel junction

InGaN/GaN light-emitting diode with a polarization tunnel junction

On the internal quantum efficiency for InGaN/GaN light-emitting diodes grown on insulating substrates

Calculating the Effect of AlGaN Dielectric Layers in a Polarization Tunnel Junction on the Performance of AlGaN-Based Deep-Ultraviolet Light-Emitting Diodes

Contact Info

Product

Resources

About