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, a first electrical conductor portion, a second electrical conductor portion, a base sublayer and a surface sublayer having a different composition than the base sublayer,
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 second electrical conductor portion is electrically isolated from the thermal conductor portion and from the first electrical conductor portion,
wherein the thermal conductor the first electrical conductor portion and the second electrical conductor portion have an identical composition,
wherein the thermal conductor portion, the first electrical conductor portion and the second electrical conductor portion have an identical thickness;
a first insulator adhered to the surface sublayer of the electro-thermal conductor,
wherein the first insulator supports the thermal conductor portion the first electrical conductor portion, and the second electrical conductor portion relative to each other and maintains the gap between the thermal conductor portion and the first electrical conductor portion; and
wherein the electro-thermal conductor comprising stress relieving openings disposed on the thermal conductor portion, the first electrical conductor portion and the second electrical conductor portion.
2. The interconnect circuit of claim 1 ,
wherein the first insulator is a device-side insulator and comprises a first opening, and
wherein the first opening is aligned with the first electrical conductor portion of the electro-thermal conductor.
3. The interconnect circuit of claim 1 , further comprising a second insulator such that the electro-thermal conductor is disposed between and adhered to both the first insulator and the second insulator.
4. The interconnect circuit of claim 3 , wherein the second insulator comprises one or more openings overlapping with at least the thermal conductor portion.
5. The interconnect circuit of claim 3 ,
wherein the first insulator is adhered to the electro-thermal conductor using a first adhesive,
wherein the second insulator is adhered to the electro-thermal conductor using a second adhesive, and
wherein a melt flow index of the first adhesive is less than a melt flow index of the second adhesive.
6. The interconnect circuit of claim 5 , wherein the second adhesive at least partially fills the gap defined by the space between the thermal conductor portion and the first electrical conductor portion and between the first insulator and the second insulator.
7. The interconnect circuit of claim 5 , wherein the gap comprises more of the second adhesive than the first adhesive by volume.
8. The interconnect circuit of claim 1 , wherein the gap between the thermal conductor portion and the first electrical conductor portion is empty.
9. The interconnect circuit of claim 1 , wherein the gap has an aspect ratio of less than about 10.
10. The interconnect circuit of claim 1 , wherein the electro-thermal conductor has a thickness of at least about 50 micrometers.
11. An interconnect circuit comprising:
an electro-thermal conductor comprising a thermal conductor portion, a first electrical conductor portion, a base sublayer and a surface sublayer having a different composition than the base sublayer,
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,
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
wherein the electro-thermal conductor comprising stress relieving openings disposed on the thermal conductor portion, the first electrical conductor portion.
12. The interconnect circuit of claim 11 , wherein the thermally conductive adhesive is a thermally conductive pressure-sensitive adhesive (PSA) film.
13. The interconnect circuit of claim 11 , further comprising 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.
14. The interconnect circuit of claim 11 , wherein the thermally conductive adhesive is electrically insulating.
15. The interconnect circuit of claim 11 , wherein the thermally conductive adhesive comprises thermally-conductive electrically-insulating particles.
16. The interconnect circuit of claim 11 , wherein the thermally conductive adhesive is adhered directly to the electro-thermal conductor.
17. 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,
wherein the thermal conductor portion and the first electrical conductor portion have an identical thickness,
wherein the electro-thermal conductor comprises a base sublayer and a surface sublayer having a different composition than the base sublayer;
a first insulator adhered to the thermal conductor portion and to the first electrical conductor portion,
wherein the first insulator is laminated over the surface sublayer of the electro-thermal conductor, 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; and
wherein the electro-thermal conductor comprising stress relieving openings disposed on the thermal conductor portion, the first electrical conductor portion.
18. The interconnect circuit of claim 17 , wherein the base sublayer comprises a metal selected from the group consisting of aluminum, an aluminum alloy, nickel, copper, and steel.
19. The interconnect circuit of claim 18 , wherein the surface sublayer comprises a metal selected from the group consisting of tin, lead, zinc, nickel, silver, palladium, platinum, gold, indium, tungsten, molybdenum, chrome, and copper.
20. The interconnect circuit of claim 17 , wherein the electro-thermal conductor further 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.