On the Near-Pole Hole Insertion Layer and the Far-Pole Hole Insertion Layer for Multi-Quantum-Well Deep Ultraviolet Light-Emitting Diodes.

Guanting Fang,Min Zhang,Dayuan Xiong

doi:10.3390/nano12040629

Guanting Fang, Min Zhang + Show 1 more

Open Access

https://doi.org/10.3390/nano12040629

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Abstract

A novel Multi-Quantum-Well Deep Ultra Violet Light Emitting Diode (DUV-LED) device with a near-pole hole insertion layer and far-pole hole insertion layer was proposed and carefully studied. It was found that remarkable enhancements both in the light output power (LOP) and the internal quantum efficiency (IQE) could be realized by using the far-electrode hole insertion layer and near-electrode hole insertion layer compared to the conventional DUV-LED device. Inserting the near-polar hole insertion layer can increase the electric field in the hole injection layer, which will promote the ionization of the acceptor, increase the hole concentration, and enhance the light-emitting performance of the device. In addition, inserting the far-pole hole insertion layer can suppress electron leakage and promote the hole injection. At the same time, the updated electron barrier height of P-AlGaN/GaN will indirectly weaken the electrostatic field in the hole injection layer, which remains inconducive to the ionization of the acceptor, implying that the electrostatic field between the P-AGaN/GaN layer can optimize the efficiency droop of the device.

Highlights

Due to the outbreak of the 2019 Corona Virus Disease (COVID-19), methods to effectively prevent and control COVID-19 have quickly become one of the most popular topics
It is rarely considered that the piezoelectric polarization field between the hole injection layer and the contact layer affects the performance of the Deep Ultra Violet Light Emitting Diode (DUV-LED)
It was found that remarkable enhancements both in the light output power (LOP) and internal quantum efficiency (IQE) could be realized by employing a that remarkable enhancements both in the LOP and IQE could be realized by employing far-electrode hole insertion layer and near-electrode hole insertion layer compared with the a far-electrode hole insertion layer and near-electrode hole insertion layer compared with conventional AlGaN-based deep ultraviolet (DUV)-LEDs

Summary

Structure and Parameter

The traditional AlGaN-based DUV-LED structure, deemed as the reference (labeled as ALED), is usually grown on a c-plane sapphire substrate. Based on the reference structure (i.e., ALED), three modified structures are proposed and compared critically (labeled as BLED, CLED and BCLED). The structure of BLED is identical to ALED except for near-pole hole insertion layer, which inserts a 5-nm-thick Mg-doped Al0.35 Ga0.65 N insertion layer (labeled as the near-pole hole layer) between the Al0.40 Ga0.60 N hole injection layer and p-GaN contact layer. The structure BCLED is based on the structure ALED in which the near-pole hole insertion layer and the far-pole hole insertion layer are inserted. The four structures (ALED, BLED, CLED, BCLED) are studied using the Advanced Physical Model of Semiconductor Devices (APSYS) simulation software [20]. The light extraction efficiency is set to ~8% for DUV-LEDs charge density is 40% [25,26].

Results and Discussion

Comparison between

Conclusions