Systems and methods for combined thermal and electrical energy transfer
Provided are interconnect circuits for combined electrical and thermal energy transfer to devices connected to these circuits. Also provided are methods of fabricating such interconnect circuits. An interconnect circuit may include an electro-thermal conductor and at least one insulator providing support to different portions of the conductor with respect to each other. The insulator may include one or more openings for electrical connections and/or heat exchange with the electro-thermal conductor. The portions of the conductor may be electrically isolated from each other in the final circuit. Initially, these portions may be formed from the same conductive sheet, such as a metal foil having a thickness of at least about 50 micrometers. This thickness ensures sufficient thermal transfer in addition to providing excellent electrical conductance. In some embodiments, the conductor may include a surface coating to protect its base material from oxidation, enhancing electrical connections, and/or other purposes.
1. An interconnect circuit comprising:
an electro-thermal conductor comprising a thermal conductor portion and a first electrical conductor portion,
wherein the thermal conductor portion is electrically isolated from the first electrical conductor portion by a gap defining a boundary of the first electrical conductor portion,
wherein the thermal conductor portion and the first electrical conductor portion have an identical composition and each of the thermal conductor portion and the first electrical conductor portion comprises a base sublayer and a surface sublayer having a different composition than the base sublayer,
wherein the base sublayer comprises aluminum, and
wherein the thermal conductor portion and the first electrical conductor portion have an identical thickness;
a first insulator adhered to the surface sublayer of the thermal conductor portion and to the first electrical conductor portion,
wherein the first insulator supports the thermal conductor portion and the first electrical conductor portion relative to each other and maintains the gap between the thermal conductor portion and the first electrical conductor portion;
a thermally conductive adhesive adhered to the electro-thermal conductor such that the electro-thermal conductor is disposed between the thermally conductive adhesive and the first insulator; and
a heat sink adhered to the thermally conductive adhesive such that the thermally conductive adhesive is disposed between the heat sink and the electro-thermal conductor, wherein the heat sink is thermally coupled to the electro-thermal conductor by the thermally conductive adhesive.
2. The interconnect circuit of claim 1 , wherein the thermally conductive adhesive is a thermally conductive pressure-sensitive adhesive (PSA) film.
3. The interconnect circuit of claim 1 , wherein the thermally conductive adhesive is electrically insulating.
4. The interconnect circuit of claim 1 , wherein the thermally conductive adhesive comprises thermally-conductive electrically-insulating particles.
5. The interconnect circuit of claim 1 , wherein the thermally conductive adhesive is adhered directly to the electro-thermal conductor.
6. The interconnect circuit of claim 1 , wherein the thermally conductive adhesive is a multi-layered stack comprising two adhesive sub-layers and an insulator sub-layer disposed between the two adhesive sub-layers.
7. The interconnect circuit of claim 1 , wherein the heat sink is a housing.
8. The interconnect circuit of claim 1 , wherein the surface sublayer comprises copper.
9. The interconnect circuit of claim 1 , wherein each of the thermal conductor portion and the first electrical conductor portion comprises an intermediate sublayer disposed between the base sublayer and the surface sublayer and having a different composition than the base sublayer and the surface sublayer.
10. The interconnect circuit of claim 9 , wherein the base sublayer comprises aluminum, the intermediate sublayer comprises nickel, and the surface sublayer comprises copper.
11. The interconnect circuit of claim 1 , wherein a surface of the first insulator facing away from the electro-thermal conductor is a reflective surface.
12. interconnect circuit of claim 11 , wherein the surface of the first insulator facing away from the electro-thermal conductor has a total reflectance of greater than 50% and has a diffuse reflectance of greater than 25%.
13. The interconnect circuit of claim 11 , wherein the first electrical conductor portion comprises a first contact portion formed by the surface sublayer, wherein the thermal conductor portion comprises a second contact portion formed by the surface sublayer, and wherein the first contact portion and the second contact portion are exposed through at least one opening in the first insulator.
14. The interconnect circuit of claim 1 , wherein the gap between the thermal conductor portion and the first electrical conductor portion is exposed.
15. The interconnect circuit of claim 1 , wherein the gap between the thermal conductor portion and the first electrical conductor portion is filled with the thermally conductive adhesive.
16. An assembly comprising:
a device; and
an interconnect circuit comprising:
an electro-thermal conductor comprising a thermal conductor portion and a first electrical conductor portion,
wherein the thermal conductor portion is electrically isolated from the first electrical conductor portion by a gap defining a boundary of the first electrical conductor portion,
wherein the thermal conductor portion is electrically coupled to the device,
wherein the first electrical conductor portion is electrically coupled to the device,
wherein the thermal conductor portion and the first electrical conductor portion have an identical composition and each of the thermal conductor portion and the first electrical conductor portion comprises a base sublayer and a surface sublayer having a different composition than the base sublayer,
wherein the base sublayer comprises aluminum, and
wherein the thermal conductor portion and the first electrical conductor portion have an identical thickness;
a first insulator adhered to the surface sublayer of the electro-thermal conductor and to the first electrical conductor portion,
wherein the first insulator supports the thermal conductor portion and the first electrical conductor portion relative to each other and maintains the gap between the thermal conductor portion and the first electrical conductor portion;
a thermally conductive adhesive adhered to the electro-thermal conductor such that the electro-thermal conductor is disposed between the thermally conductive adhesive and the first insulator; and
a housing adhered to the thermally conductive adhesive such that the thermally conductive adhesive is disposed between the housing and the electro-thermal conductor, wherein the housing is thermally coupled to the electro-thermal conductor by the thermally conductive adhesive.
17. The assembly of claim 16 , wherein the device is a light emitting diode.
18. The assembly of claim 16 , wherein the device is thermally coupled to at least the thermal conductor portion of the electro-thermal conductor.