LED phosphor suppliers are affected by China's rare-earth export quotas (MAGAZINE)
LED phosphors typically incorporate rare-earth elements, and manufacturers need to ensure that they have an adequate supply of these critical materials, as TIM WHITAKER reports.
The 17 rare-earth elements comprise the lanthanide series in the periodic table (elements 57 through 71), plus scandium (Sc) and yttrium (Y). The most common LED phosphor is yttrium aluminum garnet (YAG) doped with cerium (Ce), another rare earth, while TAG phosphor contains terbium (Tb). Silicate phosphors such as BOSE and nitride phosphors are commonly doped with Ce or europium (Eu).
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