Multi-chip light emitter packages and related methods
View Patent ↗Light emitter packages having multiple light emitter chips, such as light emitting diode (LED) chips, and related methods are provided. In one embodiment, a light emitter package can include a ceramic submount. An array of light emitter chips can be disposed over a portion of the submount, and each light emitter chip can include a horizontal chip structure having positive and negative electrical contacts disposed on a same side. The positive and negative electrical contacts can be adapted to electrically communicate to conductive portions of the submount. Light emitter packages can further include a lens overmolded on the submount and covering a portion of the array.
1. A method of providing a light emitter package, the method comprising:
providing a submount having a planar upper surface;
providing an array of light emitter chips disposed over a portion of the planar upper surface of the submount in a rectangular arrangement;
connecting each light emitter chip of the array of light emitter chips to conductive portions of the submount via non-wire bond connections; and
providing a lens over the array of light emitter chips, wherein the lens is asymmetric about a central axis of the submount that is orthogonal to the planar upper surface of the submount.
2. The method of claim 1 , wherein directly connecting each light emitter chip comprises connecting the bottom side of each light emitter chip to conductive portions of the submount via a eutectic direct die attach process.
3. The method of claim 1 , wherein conductive portions of the submount comprise a positive contact pad, a negative contact pad, and at least one intermediate contact pad.
4. The method of claim 3 , further comprising providing portions of intermediate contact pad between portions of the positive and negative contact pads.
5. The package of claim 1 , wherein providing an asymmetric lens comprises overmolding the asymmetric lens.
6. The method of claim 1 , wherein each light emitter chip comprises a horizontal chip structure having positive and negative electrical contacts disposed on a same side.
7. The method of claim 6 , wherein the positive and negative electrical contacts are disposed on a bottom side of each light emitter chip.
8. A light emitter package comprising:
an array of light emitter chips disposed on a submount in a rectangular arrangement and connected without wire bonds, wherein the array of light emitter chips comprises a center point coincident with the center point of the submount;
a lens disposed over the array of light emitter chips, and wherein the lens is asymmetric about the center point of the array of light emitter chips; and
a positive electrical pad, an intermediate electrical pad, and a negative electrical pad.
9. The package of claim 8 , wherein a portion of the intermediate contact pad is disposed between portions of the positive and negative contact pads.
10. The package of claim 8 , wherein a portion of the positive contact pad is adjacent to a portion of the negative contact pad.
11. The package of claim 8 , wherein the positive contact pad is adjacent to intermediate contact pad along at least three sides.
12. The package of claim 8 , wherein the negative contact pad is adjacent to intermediate contact pad along at least three sides.
13. The package of claim 8 , wherein the array defines an LED chip-populated area having an aspect ratio greater than 1.
14. The package of claim 8 , wherein the array defines an LED chip-populated area having an aspect ratio greater than 2.
15. The package of claim 8 , wherein the array defines an LED chip-populated area having an aspect ratio greater than 3.
16. A light emitter package comprising:
a submount comprising a ceramic material having a planar upper surface;
an array of light emitter chips disposed on a portion of the planar upper surface of the submount, wherein each light emitter chip comprises a horizontal chip structure having positive and negative electrical contacts disposed on a same side, wherein the positive and negative electrical contacts are adapted to electrically communicate to conductive portions of the submount; and
a lens overmolded on the planar upper surface of the submount and covering a portion of the array, wherein the lens is asymmetric about a central axis of the submount that is orthogonal to the planar upper surface of the submount.
17. The package of claim 16 , wherein the package is adapted to deliver approximately 100 lumens per watt (LPW) or more at 1.5 amps (A) and/or 9 watts (W).
18. The package of claim 16 , wherein the package is configured to refract light emitted by the array of light emitter chips toward a preferential direction.
19. The package of claim 18 , wherein:
the array of light emitter chips defines an emitter axis; and
the lens has an outer surface and a centerline which is offset from the emitter axis toward the preferential direction.
20. The package of claim 1 , wherein the package comprises a first contact pad, a second contact pad, and a third contact pad.
21. The package of claim 20 , wherein each of the first, second, and third contact pads comprise centrally disposed leg portions.
22. The package of claim 21 , wherein leg portions of the second contact pad are disposed between leg portions of the first and third contact pads.
23. The package of claim 16 , wherein the light emitter chips comprise light emitting diode (LED) chips.
24. The package of claim 23 , wherein the LED chips are approximately 1000 μm×1000 μm in size.
25. The package of claim 23 , wherein the LED chips are approximately 350 μm ×350 μm in size.
26. The package of claim 23 , wherein the package comprises an array of eight LED chips.
27. The package of claim 23 , wherein the package comprises an array of forty-eight LED chips.