Lumiphoric material structures for light- emitting diode packages and related methods
Solid-state lighting devices including light-emitting diodes (LEDs) and more particularly lumiphoric material structures for LED packages and related methods are disclosed. Cover structures with predefined color points for LED packages may include multiple lumiphoric material structures that are bonded together and arranged within LED packages. Lumiphoric material structures may include preformed and hardened structures, such as phosphor-in-glass or phosphor-in-ceramic, that are bonded together to form cover structures. Certain lumiphoric material structures include multiple sublayers of varying quantities and/or compositions of lumiphoric materials. Lumiphoric material structures with targeted color points may also be reduced to powder form and mixed within a binder for application in LED packages. Related methods include preforming cover structures of bonded lumiphoric material structures or assembling cover structures at a package level by separately arranging each lumiphoric material structure within LED packages.
1 . A light-emitting diode (LED) package comprising:
a submount;
at least one LED chip on the submount;
a cover structure on the at least on LED chip, the cover structure comprising a first lumiphoric material structure that is bonded to a second lumiphoric material structure, and a first adhesive material between the first lumiphoric material structure and the second lumiphoric material structure, wherein at least one of the first lumiphoric material structure and the second lumiphoric material structure comprises a plurality of compressed sublayers with laterally varying quantities or compositions of lumiphoric particles; and
a second adhesive material between the first lumiphoric material structure and the at least one LED chip.
2 . The LED package of claim 1 , wherein each of the first lumiphoric material structure and the second lumiphoric material structure comprises a phosphor-in-glass structure or a phosphor-in-ceramic structure.
3 . The LED package of claim 1 , wherein:
the at least one LED chip is configured to emit light of a first peak wavelength;
the first lumiphoric material structure is configured to convert a portion of the first peak wavelength to light of a second peak wavelength;
the second lumiphoric material structure is configured to convert another portion of the first peak wavelength to light of a third peak wavelength; and
the first peak wavelength, the second peak wavelength, and the third peak wavelength are all different from one another.
4 . The LED package of claim 3 , wherein:
the first lumiphoric material structure is arranged closer to the at least one LED chip than the second lumiphoric material structure; and
the second peak wavelength is greater than the third peak wavelength.
5 . The LED package of claim 1 , wherein the first adhesive material and the second adhesive material are light-transparent to wavelengths of light provided by the first lumiphoric material structure and the second lumiphoric material structure.
6 . The LED package of claim 1 , wherein a first thickness of the first lumiphoric material structure is less than a second thickness of the second lumiphoric material structure.
7 . The LED package of claim 1 , wherein the first lumiphoric material structure comprises the plurality of compressed sublayers with varying quantities or compositions of lumiphoric particles and the second lumiphoric material structure comprises another plurality of compressed sublayers with varying quantities or compositions of lumiphoric particles.
8 . The LED package of claim 1 , wherein at least one sublayer of the plurality of sublayers comprises a first subregion that includes lumiphoric particles and a second subregion that is devoid of lumiphoric particles.
9 . The LED package of claim 8 , wherein the second subregion is laterally arranged about a perimeter of the first subregion.
10 . The LED package of claim 1 , wherein the cover structure comprises a third lumiphoric material structure that is bonded to the second lumiphoric material structure.