Donor-acceptor-codoped SiC was recognized as a candidate of blue LED material in 1970s-1980s. However, very few works on optical device applications of SiC are recently conducting, because many scientists and researchers believe that the indirect bandgap material including SiC is not suitable for optical use. In 2006, a concept of fluorescent SiC (f-SiC), which is a thick 6H-SiC epilayer and contains donor and acceptor impurities, was proposed. The f-SiC works as a phosphor and it is not an electrically excited material like LEDs. And a monolithic white LED, composed of the f-SiC substrate and over-grown nitride-based near UV LED stack was demonstrated. A combination of the f-SiC and porous SiC, which is made from the f-SiC by anodic oxidation was reported to show pure white light emission with a color rendering index of 81. Advantages of f-SiC based phosphor might be its chemical stability and the superior temperature characteristics, compared with current powder phosphors used in white LEDs. Thus, in this talk, optical properties of f-SiC and porous f-SiC, and performance of the white LED in combination with the f-SiC substrate and a nitride-based near UV LED are given.

Date Published: 5 March 2019
PDF
Proc. SPIE 10918, Gallium Nitride Materials and Devices XIV, 1091820 (5 March 2019); doi: 10.1117/12.2511208

Published in SPIE Proceedings Vol. 10918:
Gallium Nitride Materials and Devices XIV
Hiroshi Fujioka; Hadis Morkoç; Ulrich T. Schwarz, Editor(s)