Journal:Optical Materials Express

Abstract:Insufficient hole injection and current nonuniformity caused by the nature of the p-AlGaN hole injection layer (HIL) are two issues impending the advances in the optical and electrical properties of AlGaN-based deep ultraviolet light-emitting diodes (DUV LEDs). To simultaneously improve the hole injection efficiency and current uniformity, an Al-linearly-decreasing AlGaN PN junction (ALD AlGaN PN junction) is proposed to replace the conventional p-AlGaN HIL with constant Al component. The barrier height for holes at the interface between the p-type electron blocking layer (p-EBL) and HIL as well as the hole concentration and resistance in the p-AlGaN HIL can be modulated at the same time by the proposed ALD AlGaN PN junction. As a result, the hole injection efficiency is enhanced due to the reduced barrier height at the p-EBL/HIL interface and the polarization-induced three-dimensional hole gas (3DHG) induced in the proposed ALD PN junction HIL. In addition, the lateral current uniformity is improved by the properly regulated resistance in the p-AlGaN HIL, which can be ascribed to the additional barrier for holes in the valence band because of the incorporated ALD AlGaN PN junction. The proposed DUV LED with ALD AlGaN PN junction exhibits enhanced EQE by a factor of 39.2% and simultaneously improved current uniformity in the active region. This designed ALD AlGaN PN junction structure provides a promising strategy for achieving high-performance DUV LEDs.

All the Authors:Wentao Tian

First Author:Mengran Liu

Indexed by:Journal paper

Correspondence Author:Chao Liu

Discipline:Engineering

First-Level Discipline:Electronic Science and Techonology

Document Type:J

Volume:13

Issue:8

Page Number:2405

Translation or Not:no

Date of Publication:2023-07-01

Included Journals:SCI

Simultaneously improved hole injection and current uniformity in AlGaN-based deep ultraviolet light-emitting diodes.pdf Download []Times