Reducing the polarization mismatch between the last quantum barrier and p-EBL to enhance the carrier injection for AlGaN-based DUV LEDs

In this work, we report an AlGaN-based ∼275 nm deep ultraviolet light-emitting diode (DUV LED) that has AlGaN based quantum barriers with a properly large Al composition. It is known that the increased conduction band barrier height helps to enhance the electron concentration in the active region. However, we find that the promoted hole injection efficiency is also enabled for the proposed DUV LED when the Al composition increases. This is attributed to the reduced positive polarization charge density at the last quantum barrier (LQB) and p-type electron blocking layer (p-EBL) interface, which can suppress the hole depletion effect in the p-EBL. Thus, the hole concentration in the p-EBL gets promoted, which is very helpful to reduce the hole blocking effect caused by the p-EBL. Therefore, thanks to the improved carrier injection, the proposed DUV LED increases the optical power and reduces the forward voltage when compared with the conventional DUV LED.

[1]  Wei Guo,et al.  Efficiency Droop Suppression and Light Output Power Enhancement of Deep Ultraviolet Light-Emitting Diode by Incorporating Inverted-V-Shaped Quantum Barriers , 2020, IEEE Transactions on Electron Devices.

[2]  Zi-hui Zhang,et al.  Improving hole injection from p-EBL down to the end of active region by simply playing with polarization effect for AlGaN based DUV light-emitting diodes , 2020 .

[3]  Haiding Sun,et al.  Nearly Efficiency-Droop-Free AlGaN-Based Deep-Ultraviolet Light-Emitting Diode Without Electron-Blocking Layer , 2020, Journal of Electronic Packaging.

[4]  Jing Zhang,et al.  Physics of high-efficiency 240–260 nm deep-ultraviolet lasers and light-emitting diodes on AlGaN substrate , 2020 .

[5]  Ramit Kumar Mondal,et al.  Effect of step-graded superlattice electron blocking layer on performance of AlGaN based deep-UV light emitting diodes , 2019, Physica E: Low-dimensional Systems and Nanostructures.

[6]  T. Seong,et al.  The emergence and prospects of deep-ultraviolet light-emitting diode technologies , 2019, Nature Photonics.

[7]  J. Ryou,et al.  III-Nitride Deep UV LED Without Electron Blocking Layer , 2019, IEEE Photonics Journal.

[8]  Zi-hui Zhang,et al.  Progress in External Quantum Efficiency for III‐Nitride Based Deep Ultraviolet Light‐Emitting Diodes , 2019, physica status solidi (a).

[9]  M. R. Wagner,et al.  Auger recombination in AlGaN quantum wells for UV light-emitting diodes , 2018, Applied Physics Letters.

[10]  H. Kuo,et al.  Establishment of the relationship between the electron energy and the electron injection for AlGaN based ultraviolet light-emitting diodes. , 2018, Optics Express.

[11]  M. Shephard,et al.  Stochasticity in materials structure, properties, and processing-A review. , 2018, Applied physics reviews.

[12]  H. Morkoç,et al.  Status of Growth of Group III-Nitride Heterostructures for Deep Ultraviolet Light-Emitting Diodes , 2017 .

[13]  H. Kuo,et al.  Hole Transport Manipulation To Improve the Hole Injection for Deep Ultraviolet Light-Emitting Diodes , 2017 .

[14]  Xiaodong Wang,et al.  Performance improvement of AlGaN-based deep-ultraviolet light-emitting diodes by inserting single spike barriers , 2016 .

[15]  Li Chen,et al.  Multiuser Diversity Over Parallel and Hybrid FSO/RF Links and Its Performance Analysis , 2016, IEEE Photonics Journal.

[16]  Yanan Guo,et al.  Tailoring of Energy Band in Electron-Blocking Structure Enhancing the Efficiency of AlGaN-Based Deep Ultraviolet Light-Emitting Diodes , 2016, IEEE Photonics Journal.

[17]  Y. Kuo,et al.  Numerical Investigation on the Carrier Transport Characteristics of AlGaN Deep-UV Light-Emitting Diodes , 2016, IEEE Journal of Quantum Electronics.

[18]  Dunjun Chen,et al.  AlGaN-Based Multiple Quantum Well Deep Ultraviolet Light-Emitting Diodes With Polarization Doping , 2016, IEEE Photonics Journal.

[19]  G. Wang,et al.  High hole concentration in p-type AlGaN by indium-surfactant-assisted Mg-delta doping , 2015 .

[20]  Yong Zhang,et al.  Investigation of AlGaN-based deep-ultraviolet light-emitting diodes with composition-varying AlGaN multilayer barriers , 2014 .

[21]  Xiao Wei Sun,et al.  Improving hole injection efficiency by manipulating the hole transport mechanism through p-type electron blocking layer engineering. , 2014, Optics letters.

[22]  Wei Liu,et al.  On the mechanisms of InGaN electron cooler in InGaN/GaN light-emitting diodes. , 2014, Optics express.

[23]  J. Piprek.  Ultra-violet light-emitting diodes with quasi acceptor-free AlGaN polarization doping , 2012 .

[24]  Miao-Chan Tsai,et al.  Deep-ultraviolet light-emitting diodes with gradually increased barrier thicknesses from n-layers to p-layers , 2011 .

[25]  Debdeep Jena,et al.  Polarization-Induced Hole Doping in Wide–Band-Gap Uniaxial Semiconductor Heterostructures , 2010, Science.

[26]  K. B. Nam,et al.  Unique optical properties of AlGaN alloys and related ultraviolet emitters , 2004 .

[27]  Jerry R. Meyer,et al.  Band parameters for nitrogen-containing semiconductors , 2003 .

[28]  J. Li,et al.  Enhanced p-type conduction in GaN and AlGaN by Mg-δ-doping , 2003 .

[29]  H. Amano,et al.  Thermal ionization energy of Si and Mg in AlGaN , 1998 .

[30]  W. Grieshaber,et al.  Enhancement of deep acceptor activation in semiconductors by superlattice doping , 1996 .