High voltage low current surface emitting LED
View Patent ↗An LED chip comprising a plurality of sub-LEDs on a submount. Electrically conductive and electrically insulating features are included that serially interconnect the sub-LEDs such that an electrical signal applied to the serially interconnected sub-LEDs along the electrically conductive features spreads to the serially interconnected sub-LEDs. A via is included that is arranged to electrically couple one of the sub-LEDs to the submount. The sub-LEDs can be interconnected by more than one of the conductive features, with each one of the conductive features capable of spreading an electrical signal between two of the sub-LEDs.
1. A LED chip, comprising:
a plurality of sub-LEDs collectively bonded by a common bond layer to a submount, wherein the common bond layer does not electrically interconnect the plurality of sub-LEDs;
electrically conductive and electrically insulating features serially interconnecting said sub-LEDs; and
at least one via arranged to electrically couple at least one of said sub-LEDs to said submount.
2. The LED chip of claim 1 , wherein said submount is electrically conductive, an electrical signal on said via passing through said submount.
3. The LED chip of claim 1 , wherein said submount is electrically insulating, said via running through said submount.
4. The LED chip of claim 1 , further comprising a wire bond pad electrically coupled to said first of said serially interconnected sub-LEDs, said via electrically coupled to the last of said serially interconnected sub-LEDs.
5. The LED chip of claim 1 , wherein an electrical signal applied across the wire bond pad and said via causes said sub-LEDs to emit light.
6. The LED chip of claim 1 , wherein said sub-LEDs are formed from a single junction LED.
7. The LED chip of claim 1 , comprising a plurality of electrically conductive features serially interconnecting two of said sub-LEDs, each said electrically conductive feature capable of spreading said electrical signal between said two of said sub-LEDs.
8. The LED chip of claim 1 , further comprising an insulator layer between said submount and said sub-LEDs.
9. The LED chip of claim 1 , wherein the voltage necessary to drive said sub-LEDs is dependent on the number of said serially interconnected sub-LEDs and the junction voltage of said sub-LEDs.
10. The LED chip of claim 1 , wherein the active area utilization ratio is greater than 50%.
11. The LED chip of claim 1 , wherein the active area utilization ratio is greater than 75%.
12. The LED chip of claim 1 , wherein said sub-LEDs are flip-chip mounted on said substrate.
13. The LED chip of claim 1 , wherein the alignment tolerance between said sub-LEDs is less than 5 microns.
14. The LED chip of claim 1 , wherein the alignment tolerance between said sub-LEDs is less than 2 microns.
15. The LED chip of claim 1 , emitting a white light from said sub-LEDs.
16. A LED chip, comprising:
a plurality of sub-LEDs mounted on a submount;
connector traces serially interconnecting said sub-LEDs;
insulating features to insulate portions of said sub-LEDs from said connector traces;
at least one bottom contact disposed between at least one of said sub-LEDs and said submount; and
at least one via extending perpendicularly from said submount to contact a sidewall of said at least one bottom contact of said at least one of said sub-LEDs.
17. The LED chip of claim 16 , further comprising a plurality of bottom contacts, each of which is between one of said sub-LEDs and said submount.
18. The LED chip of claim 16 , further comprising a metal stack and an insulating layer arranged between said sub-LEDs and said submount, said via passing through said insulating layer.
19. The LED chip of claim 16 , wherein said submount is electrically conductive, and wherein said via contacts said submount.
20. The LED chip of claim 16 , wherein said submount is electrically insulating, said via running through said submount.
21. The LED chip of claim 16 , further comprising a wire bond pad electrically coupled to said first of said serially interconnected sub-LEDs, said via electrically coupled to the last of said serially interconnected sub-LEDs.
22. The LED chip of claim 16 , wherein an electrical signal applied across the wire bond pad and said via causes said sub-LEDs to emit light.
23. The LED chip of claim 16 , wherein an electrical signal applied across the wire bond pad and said submount causes said sub-LEDs to emit light.
24. The LED chip of claim 16 , wherein at least two of said sub-LEDs is interconnected by a plurality of said connector traces.
25. A LED chip, comprising:
a plurality of sub-LEDs on a submount; and
a plurality of electrically conductive features serially interconnecting at least some of said sub-LEDs, wherein at least two of said sub-LEDs are electrically interconnected by more than one of said conductive features that provide at least one redundant electrical connection between the at least two of said sub-LEDs, each one of said conductive features capable of spreading an electrical signal between said two of said sub-LEDs.
26. The LED chip of claim 25 , wherein said more than one conductive features comprise at least two conductive traces.
27. The LED chip of claim 25 , wherein each of said conductive features is capable of spreading an electrical signal between said two of said sub-LEDs such that said sub-LEDs emit light in response to said signal.
28. The LED chip of claim 25 , further comprising insulating features cooperating with said conductive features to allow said signal to spread between said two of said sub-LEDs.
29. A LED chip, comprising:
a plurality of sub-LEDs on a submount; and
a plurality of electrically conductive paths serially connecting at least some of said sub-LEDs, wherein first and second contacts of respective adjacent first and second ones of said serially connected sub-LEDs are connected by more than one of said electrically conductive paths.