Next Article in Journal
Wind Loads on a Solar Panel at High Tilt Angles
Previous Article in Journal
BIM-Based AR Maintenance System (BARMS) as an Intelligent Instruction Platform for Complex Plumbing Facilities
Previous Article in Special Issue
Analysis of Quality Factor Enhancement in the Monolithic InGaN/GaN Nanorod Array
Article Menu
Issue 8 (April-2) cover image

Export Article

Open AccessReview

Distributed Bragg Reflectors for GaN-Based Vertical-Cavity Surface-Emitting Lasers

Department of Electrical Engineering, Yale University, New Haven, CT 06520, USA
Author to whom correspondence should be addressed.
Appl. Sci. 2019, 9(8), 1593;
Received: 14 March 2019 / Revised: 12 April 2019 / Accepted: 15 April 2019 / Published: 17 April 2019
(This article belongs to the Special Issue Group III-V Nitride Semiconductor Microcavities and Microemitters)
PDF [5587 KB, uploaded 29 April 2019]


A distributed Bragg reflector (DBR) is a key building block in the formation of semiconductor microcavities and vertical cavity surface emitting lasers (VCSELs). The success in epitaxial GaAs DBR mirrors paved the way for the ubiquitous deployment of III-V VCSELs in communication and mobile applications. However, a similar development of GaN-based blue VCSELs has been hindered by challenges in preparing DBRs that are mass producible. In this article, we provide a review of the history and current status of forming DBRs for GaN VCSELs. In general, the preparation of DBRs requires an optimization of epitaxy/fabrication processes, together with trading off parameters in optical, electrical, and thermal properties. The effort of epitaxial DBRs commenced in the 1990s and has evolved from using AlGaN, AlN, to using lattice-matched AlInN with GaN for DBRs. In parallel, dielectric DBRs have been studied since 2000 and have gone through a few design variations including epitaxial lateral overgrowth (ELO) and vertical external cavity surface emitting lasers (VECSEL). A recent trend is the use of selective etching to incorporate airgap or nanoporous GaN as low-index media in an epitaxial GaN DBR structure. The nanoporous GaN DBR represents an offshoot from the traditional epitaxial approach and may provide the needed flexibility in forming manufacturable GaN VCSELs. The trade-offs and limitations of each approach are also presented. View Full-Text
Keywords: distributed Bragg reflector; VCSEL; GaN distributed Bragg reflector; VCSEL; GaN

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Zhang, C.; ElAfandy, R.; Han, J. Distributed Bragg Reflectors for GaN-Based Vertical-Cavity Surface-Emitting Lasers. Appl. Sci. 2019, 9, 1593.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Appl. Sci. EISSN 2076-3417 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top