Abstract
In the present work, antireflective sub-wavelength structures have been fabricated on fluorescent 6H-SiC to enhance the white light extraction efficiency by using the reactive-ion etching method. Broadband and omnidirectional antireflection characteristics show that 6H-SiC with antireflective sub-wavelength structures suppress the average surface reflection significantly from 20.5 % to 1.01 % over a wide spectral range of 390-784 nm. The luminescence intensity of the fluorescent 6H-SiC could be enhanced in the whole emission angle range. It maintains an enhancement larger than 91 % up to the incident angle of 70 degrees, while the largest enhancement of 115.4 % could be obtained at 16 degrees. The antireflective sub-wavelength structures on fluorescent 6H-SiC could also preserve the luminescence spectral profile at a large emission angle by eliminating the Fabry-Pérot microcavity interference effect.
Highlights
White light-emitting diodes (LEDs) consisting of a nitride-based blue LED chip and phosphor are very promising candidates for the general lighting applications as energy-saving and environment friendly light sources [1,2,3,4,5]
In the present work, antireflective sub-wavelength structures have been fabricated on fluorescent 6H-SiC to enhance the white light extraction efficiency by using the reactive-ion etching method
The luminescence intensity of the fluorescent 6H-SiC could be enhanced in the whole emission angle range
Summary
White light-emitting diodes (LEDs) consisting of a nitride-based blue LED chip and phosphor are very promising candidates for the general lighting applications as energy-saving and environment friendly light sources [1,2,3,4,5]. Donor-acceptor doped fluorescent SiC has been proven as a highly efficient wavelength converter material much superior to the phosphors in terms of high color rendering index (CRI) value and long lifetime [6, 7]. The donor-acceptorpair (DAP) band luminescences from the nitrogen (N)-boron (B) doped 6H-SiC present a warmwhite color. Combined with the DAP luminescences from the nitrogen-aluminium doped 6HSiC, pure white light with CRI larger than 90 could be produced [8, 9]. Applying the ARS on SiC has been studied on the monochromatic LEDs with undoped SiC as substrate materials [14, 15] and on the 4H-SiC photodiodes [16]. The effect of ARS on the fluorescent SiC to enhance the light extraction efficiency over the entire visible spectral range has been studied
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
