US 12,438,130 B2
Light emitting diode filament including chip scale package light emitting diodes to reduce the amount of phosphor that is integrated into the filament
Xinrong Wang, Shenzhen (CN); Tianzheng Jiang, Shenzhen (CN); and Ming Li, Acton, MA (US)
Assigned to LEDVANCE LLC, Wilmington, MA (US)
Filed by LEDVANCE LLC, Wilmington, MA (US)
Filed on Nov. 2, 2021, as Appl. No. 17/517,037.
Prior Publication US 2023/0137752 A1, May 4, 2023
Int. Cl. H01L 25/00 (2006.01); C09K 11/77 (2006.01); F21V 21/005 (2006.01); H01L 25/075 (2006.01); H10H 20/01 (2025.01); H10H 20/825 (2025.01); H10H 20/851 (2025.01); H10H 20/853 (2025.01); H10H 20/857 (2025.01)
CPC H01L 25/0753 (2013.01) [C09K 11/7774 (2013.01); F21V 21/005 (2013.01); H10H 20/01 (2025.01); H10H 20/825 (2025.01); H10H 20/8512 (2025.01); H10H 20/8514 (2025.01); H10H 20/853 (2025.01); H10H 20/857 (2025.01); H10H 20/0361 (2025.01); H10H 20/0362 (2025.01); H10H 20/0364 (2025.01)] 19 Claims
OG exemplary drawing
 
1. A light emitting diode filament comprising:
a metal stent substrate;
a dielectric layer present on the metal stent substrate;
a circuit having a plurality of contact pads arranged along a length of the metal stent substrate;
light emitting diode (LED) chips engaged to the contact pads along the length of the metal stent substrate to provide that the light emitting diode (LED) chips are electrically connected in series, wherein each light emitting diode (LED) chip includes at least a light transmission surface that is in contact with an individual portion of phosphor for the LED chip, wherein the individual portion of phosphor covers an entirety of an upper surface of each light emitting diode (LED) chip and an entirety of a sidewall of each light emitting diode (LED) chip; and
a sapphire encapsulant present in direct contact with an entirety of the individual portion of phosphor on the light emitting diode chips and the sapphire encapsulant is in direct contact with a portion of the dielectric layer between the light emitting diode (LED) chips that are positioned adjacent to one another, wherein the sapphire encapsulant provides an exterior surface for the light emitting diode filament over the light emitting diode (LED) chips.