Planar GaN-Based Blue Light-Emitting Diodes With Surface p-n Junction Formed by Selective-Area Si-Ion Implantation

• Published in: IEEE transactions on electron devices Vol. 64; no. 10; pp. 4156 - 4160
• Main Authors: Lee, Ming-Lun, Yeh, Yu-Hsiang, Liu, Zi-Yuan, Chiang, Kai-Jen, Sheu, Jinn-Kong
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Annealing; Carrier injection; Current carriers; Current injection; Emission analysis; Epitaxial layers; Gallium nitride; Gallium nitrides; GaN; Homojunctions; Indium gallium nitrides; Ion implantation; Light emitting diodes; light-emitting diodes (LEDs); Optical pumping; Organic light emitting diodes; P-n junctions; Quantum well devices; Quantum wells; Silicon
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2017.2738058

A GaN-based blue light-emitting diode structure, featuring a surface GaN p-n junction formed by selective-area Si implantation on a p-GaN surface layer, serving as a carrier injector, is demonstrated. Blue InGaN/GaN multiple quantum wells (MQWs) located under the Si-implanted planar GaN p-n junction emit a single-peak spectrum without defect-related yellow luminescence (YL). The absence of YL-band is attributed to the fact that the Si-implanted GaN homojunction only behaves a carrier injector rather than a photon injector. In other words, the single-peak blue emission does not originate from optical pumping that UV light emitted from the surface GaN homojunction (i.e., the GaN band-edge emission) to pump the underlying blue InGaN/GaN MQWs. The analysis of current-voltage characteristics and dynamic resistance tentatively elucidate that the planar surface p-n junction induces extra current paths to facilitate the carrier injection at high current injection.