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 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, 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 surface sublayer of the first electrical conductor portion, wherein the first insulator supports the thermal conductor portion and the first electrical conductor portion relative to each other thereby maintaining electrical isolation between the thermal conductor portion and the first electrical conductor portion; and
a heat sink, thermally coupled to at least the electro-thermal conductor by an adhesive.
2. The interconnect circuit of claim 1 , wherein the adhesive is a pressure-sensitive adhesive (PSA) film.
3. The interconnect circuit of claim 1 , wherein the adhesive comprises thermally-conductive electrically-insulating particles.
4. The interconnect circuit of claim 1 , wherein the adhesive is adhered directly to the electro-thermal conductor.
5. The interconnect circuit of claim 1 , wherein the adhesive is adhered directly to the heat sink.
6. The interconnect circuit of claim 1 , wherein the 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 base sublayer comprises aluminum.
9. The interconnect circuit of claim 1 , wherein the surface sublayer comprises copper.
10. 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.
11. The interconnect circuit of claim 10 , the intermediate layer comprises nickel, and the surface sublayer comprises copper.
12. The interconnect circuit of claim 1 , wherein a surface of the first insulator facing away from the electro-thermal conductor is a reflective surface.
13. The interconnect circuit of claim 12 , 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%.
14. The interconnect circuit of claim 10 , 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.
15. The interconnect circuit of claim 1 , wherein a gap between the thermal conductor portion and the first electrical conductor portion is exposed.
16. An assembly comprising:
a device; and
an electro-thermal conductor, comprising a thermal conductor portion and a first electrical conductor portion,
wherein the first electrical conductor portion is electrically coupled to the device,
wherein the thermal conductor portion is electrically isolated from the first electrical conductor by a gap defining a boundary of the first electrical conductor portion and is thermally coupled to the device,
wherein 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, 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 surface sublayer of the first electrical conductor portion, wherein the first insulator supports the thermal conductor portion and the first electrical conductor portion relative to each other thereby maintaining electrical isolation between the thermal conductor portion and the first electrical conductor portion; and
a heat sink, thermally coupled to at least the electro-thermal conductor by an 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.
19. The assembly of claim 16 , wherein the heat sink is a housing enclosing the electro-thermal conductor and at least partially enclosing the device.