Re:Seoul Biosys Begins Production of Rare Earth-Free White M...
by numpad0 on Monday November 02, 2026 @12:22PM
(#50340185)
Looks like I was simply wrong with assumption that GaN could only emit blues and there are plenty of efforts made for green and red GaN LEDs with such methods as Eu doping as well as some InGaN and AlGaN structures. That makes it not pure GaN based, but there is no such things as undoped semiconductors anyway. I believe QDs are not usually made out of GaN and it also doesn't seem to be in line with the wordings used. Your theory of this being based on multiple LED sounds likely, yeah.
https://compoundsemiconductor.net/article/114125/Realising_red_GaN-based_microLEDs_with_europium-doping
https://pubs.aip.org/aip/jap/article/123/16/160901/400705/Perspective-Toward-efficient-GaN-based-red-light
https://www.researchgate.net/figure/Color-online-a-Schematic-of-an-InGaN-based-red-LED-epitaxial-structure-b_fig1_355092457
https://www.tytlabs.co.jp/en/english/review/rev402epdf/e402_007kato.pdf
If they do not use a multiple LED structure but they still have a fluorescent conversion layer, the layer must be very thin and deposited on the top surface of the LED. It could consist of "quantum dots", like in some TV panels, i.e. very small crystals which emit light of a color depending on the composition and size of the nanocrystal when illuminated with ultraviolet or blue light.
However, "quantum dot" is a term that has already been used for a long time in marketing with the intention to suggest a superior technology. If they were using this, I expect that they would have bragged about it.
So from the wording of the press release I think that a multiple LED structure is more likely than a "quantum dot" conversion layer, even if the latter would provide both a better spectrum coverage and superior aging characteristics (by avoiding a color hue shift in old LEDs).