3DIC packages with heat dissipation structures

1. A method comprising:

bonding a device die onto a package substrate;

bonding a die stack onto the device die, wherein the die stack comprises a plurality of dies, and the device die comprises:

a first portion overlapped by the die stack; and

a second portion extending laterally beyond an edge of the die stack;

dispensing a first Thermal Interface Material (TIM) onto a top surface of the die stack;

dispensing a second TIM onto the second portion of the device die;

adhering a heat dissipating lid to the first TIM; and

adhering a heat dissipating ring to the second TIM.

2. The method of claim 1 , wherein the heat dissipating lid has a first top surface coplanar with a second top surface of the heat dissipating ring, and the method further comprises:

dispensing a third TIM onto top surfaces of both the heat dissipating lid and the heat dissipating ring; and

attaching a heat sink to the third TIM.

3. The method of claim 1 further comprising dispensing an adhesive onto a top surface of the heat dissipating ring, wherein a bottom surface of the heat dissipating lid is adhered to the top surface of the adhesive.

4. The method of claim 3 , wherein the adhesive has a thermal conductivity value lower than thermal conductivity values of the first TIM and the second TIM.

5. The method of claim 3 , wherein the heat dissipating lid comprises:

a top portion having a bottom surface in contact with the first TIM; and

protruding portions extending from the bottom surface of the top portion down to contact the adhesive.

6. The method of claim 5 , wherein the die stack extends into a recess of the heat dissipating lid, with the recess formed between the protruding portions.

7. The method of claim 1 , wherein the heat dissipating lid comprises a top portion, and a protruding portion extending below the top portion to contact the first TIM.

8. The method of claim 1 further comprising forming recesses in the heat dissipating lid, with fins of the heat dissipating lid formed between the recesses, wherein the forming the recesses comprises:

forming first recesses, wherein the first recesses overlap the heat dissipating ring; and

forming second recesses, wherein the second recesses overlap the die stack.

9. The method of claim 8 , wherein the second recesses are deeper than the first recesses.

10. The method of claim 1 , wherein the device die comprises:

a high-power-consuming circuit; and

a low-power-consuming circuit consuming less power than the high-power-consuming circuit, wherein the high-power-consuming circuit is at least partially located in the second portion of the device die.

11. A method comprising:

bonding a device die onto a package substrate;

bonding a die stack to the device die, wherein the die stack comprises a plurality of dies, and the device die comprises:

a first portion overlapped by the die stack; and

a second portion extending laterally beyond an edge of the die stack;

dispensing a first TIM on a top surface of the second portion of the device die;

dispensing a first adhesive on a top surface of the package substrate; and

adhering a heat dissipating ring to the first TIM and the first adhesive, wherein the heat dissipating ring comprises:

a first portion overlapping the second portion of the device die, with the first portion of the heat dissipating ring comprising a first bottom surface contacting the first TIM; and

a second portion having a second bottom surface contacting the first adhesive.

12. The method of claim 11 further comprising:

dispensing a second TIM on top of the die stack; and

attaching a third bottom surface of a heat dissipating lid to the second TIM.

13. The method of claim 12 further comprising:

dispensing a second adhesive on a top surface of the first portion of the heat dissipating ring; and

attaching a fourth bottom surface of the heat dissipating lid to the second adhesive.

14. The method of claim 13 , wherein the heat dissipating lid comprises:

a top portion having the third bottom surface; and

a protruding portion extending below the top portion to contact the second adhesive.

15. The method of claim 11 , wherein the device die comprises:

a high-power-consuming circuit; and

a low-power-consuming circuit consuming less power than the high-power-consuming circuit, and the high-power-consuming circuit is at least partially located in the second portion of the device die.

16. A method comprising:

bonding a device die to a package substrate;

bonding a die stack to the device die, wherein the die stack comprises a plurality of dies, and the device die comprises:

a first portion overlapped by the die stack; and

a second portion extending laterally beyond an edge of the die stack;

attaching a heat dissipating ring to the package substrate through a first adhesive, and to the second portion of the device die through a first Thermal Interface Material (TIM); and

attaching a heat dissipating lid to the heat dissipating ring through a second adhesive, and to the die stack through a second TIM.

17. The method of claim 16 , wherein the first TIM and the second TIM have better thermal conductivity than the first adhesive and the second adhesive.

18. The method of claim 16 further comprising attaching a heat sink to both the heat dissipating ring and the heat dissipating lid through a third TIM.

19. The method of claim 18 further comprising forming recesses and fins in the heat sink.

20. The method of claim 16 further comprising forming recesses in both the heat dissipating lid and the heat dissipating ring, with the heat dissipating lid and the heat dissipating ring comprising fins between the recesses.