Assertion: blue led | /r/HasProperty | developed
Facets:
value: based on gallium nitride
type: OTHER
value: more recently
type: TEMPORAL
Source sentences:
text: I remember that before the modern blue LEDs appeared there were "super reds" (dope with ZnO i believe), when were they developed?
text: More recently, blue LEDs have been developed based on gallium nitride and silicon carbide materials.