Improvement of Near-Infrared Light-Emitting Diodes' Optical Efficiency Using a Broadband Distributed Bragg Reflector with an AlAs Buffer

Hyung-Joo Lee; Jin-Young Park; Lee-Ku Kwac; Jongsu Lee

doi:10.3390/nano14040349

Improvement of Near-Infrared Light-Emitting Diodes' Optical Efficiency Using a Broadband Distributed Bragg Reflector with an AlAs Buffer

Nanomaterials (Basel). 2024 Feb 12;14(4):349. doi: 10.3390/nano14040349.

Authors

Hyung-Joo Lee¹, Jin-Young Park², Lee-Ku Kwac³, Jongsu Lee⁴

Affiliations

¹ CF Technical Division, AUK Corporation, Iksan 54630, Republic of Korea.
² Korea Photonic Technology Institute (KOPTI), Gwangju 61007, Republic of Korea.
³ Graduate School of Carbon Convergence Engineering, Jeonju University, Jeonju 55069, Republic of Korea.
⁴ Department of Advanced Components and Materials Engineering, Sunchon National University, Suncheon 57922, Republic of Korea.

Abstract

This study developed an advanced 850 nm centered distributed Bragg reflector (DBR) (broadband DBR) composed of nanomaterial-based multiple structures to improve the optical efficiency of an 850 nm near-infrared light-emitting diode (NIR-LED). A combined 850 nm centered broadband DBR was fabricated by growing an 800 nm centered ten-pair DBR on a 900 nm centered ten-pair DBR (denoted as a combined DBR). The combined DBR exhibited a slightly wider peak band than conventional DBRs. Furthermore, the peak band width of the combined DBR significantly increased upon using a reflective AlAs buffer layer that reduced the overlapped reflection. The output power (20.5 mW) of NIR-LED chips using the combined DBR with an AlAs buffer layer exceeded that of a conventional 850 nm centered DBR (14.5 mW) by more than 40%. Results indicated that combining the optical conditions of wavelengths and the AlAs buffer layer effectively strengthened the broadband effect of the DBR and increased the optical efficiency of the 850 nm NIR-LED.

Keywords: AlAs; buffer layer; distributed Bragg reflector (DBR); light-emitting diode (LED); wavelength.

Grants and funding

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2016R1A6A1A03012069, 2018R1D1A1B07050752). This paper was supported (in part) by the Sunchon National University Research Fund in 2020 (grant number 2020-0221). This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. 2021R1C1C1013387).