Method for co-designing flip-chip and interposer

1. A method for co-designing a flip-chip and an interposer, comprising:

obtaining information regarding I/O pads, power pins and IR constraints of the flip-chip by a processor;

performing a bump planning procedure by the processor to obtain a minimum number of power bumps of the flip-chip corresponding to the power pins of the flip-chip according to the information, and to uniform power density of the power bumps of the flip-chip to obtain a minimum conductance of each of the power pins of the flip-chip and a bump placement of a plurality of micro bumps of the flip-chip;

performing a chip-interposer routing procedure by the processor to obtain a flow network according to the minimum conductance of the power pins and the bump placement of the micro bumps, and obtain a Re-Distribution Layer (RDL) routing of the flip-chip and an interposer routing of the interposer according to the flow network; and

mounting the flip-chip to the interposer according to the RDL routing of the flip-chip and the interposer routing of the interposer to obtain a chip-interposer structure,

wherein a distance between a die boundary of the flip-chip and the micro bump adjacent to the die boundary of the flip-chip is not greater than half of a bump pitch of the micro bumps in the bump placement.

2. The method as claimed in claim 1 , wherein the step of performing the bump planning procedure further comprises:

obtaining a total number of micro bumps of the flip-chip according to the minimum number of power bumps and number of signal bumps of the flip-chip corresponding to the I/O pads of the flip-chip,

wherein the total number of micro bumps is larger than a sum of the signal bumps and the power bumps of the flip-chip.

3. The method as claimed in claim 1 , wherein the step of performing the bump planning procedure further comprises:

obtaining the bump placement of the micro bumps of the flip-chip according to the information and the uniformed power density of power bumps of the flip-chip, wherein the micro bumps are placed uniformly in the flip-chip.

4. The method as claimed in claim 3 , wherein each of the power bumps has the same and maximum current in the flip-chip.

5. The method as claimed in claim 1 , wherein the step of performing the bump planning procedure further comprises:

obtaining an equivalent conductance of each of the power pins according to distances between the power pin and the micro bumps in the bump placement; and

obtaining the minimum conductance of each of the power pins according to the corresponding equivalent conductance and a minimum number of the power bumps of the flip-chip corresponding to the power pins of the flip-chip,

wherein the equivalent conductance of each of the power pins is larger than the corresponding minimum conductance.

6. The method as claimed in claim 1 , wherein the step of performing the chip-interposer routing procedure further comprises:

constructing the flow network according to the minimum conductance of the power pins;

obtaining a bump assignment of the power bumps of the flip-chip corresponding to the power pins of the flip-chip and signal bumps of the flip-chip corresponding to the signal pads of the flip-chip according to the flow network; and

obtaining the RDL routing of the flip-chip according to the bump assignment.

7. The method as claimed in claim 6 , wherein a total wire-length of the RDL routing is minimized.

8. The method as claimed in claim 6 , wherein the step of performing the chip-interposer routing procedure further comprises:

modeling the IR constraints according to the RDL routing to prevent IR violations of the bump assignment; and

obtaining the interposer routing according to the modeled IR constraints and the bump assignment.

9. A method for co-designing a plurality of flip-chips and an interposer, comprising:

obtaining information regarding I/O pads, power pins and IR constraints of each of the flip-chips by a processor;

obtaining a minimum number of power bumps of each of the flip-chips according to the corresponding information by the processor, respectively;

uniforming power density of the power bumps of each of the flip-chips by the processor to respectively obtain a minimum conductance of each of the power pins of the corresponding flip-chip and a bump placement of a plurality of micro bumps of the corresponding flip-chip;

constructing a flow network according to the minimum conductance of the power pins of each of the flip-chips and the corresponding bump placement of the micro bumps by the processor, respectively;

obtaining a bump assignment of the power bumps of each of the flip-chips according to all of the flow networks by the processor, respectively;

obtaining a Re-Distribution Layer (RDL) routing of each of the flip-chips according to the corresponding bump assignment by the processor, respectively;

obtaining an interposer routing of the interposer according to all of the RDL routings by the processor; and

mounting the flip-chips to the interposer according to the RDL routing of each of the flip-chips and the interposer routing of the interposer to obtain a chip-interposer structure,

wherein a distance between a die boundary of the flip-chip and the micro bump adjacent to the die boundary of the flip-chip is not greater than half of a bump pitch of the micro bumps in the bump placement.

10. The method as claimed in claim 9 , further comprising:

obtaining a total number of micro bumps of each of the flip-chips according to the minimum number of power bumps and number of signal bumps of the corresponding flip-chip, respectively,

wherein the total number of micro bumps of the flip-chip is larger than a sum of the signal bumps and the power bumps of the flip-chip.

11. The method as claimed in claim 9 , further comprising:

obtaining the bump placement of the micro bumps of each of the flip-chips according to the corresponding information and the uniformed power density of power bumps of the corresponding flip-chip,

wherein the micro bumps are placed uniformly in the corresponding flip-chip.

12. The method as claimed in claim 11 , wherein each of the power bumps has the same and maximum current in each of the flip-chips.

13. The method as claimed in claim 9 , further comprising:

obtaining an equivalent conductance of each of the power pins according to distances between the power pin and the micro bumps in the bump placement of each of the flip-chips, respectively; and

obtaining the minimum conductance of each of the power pins according to the corresponding equivalent conductance and a minimum number of the power bumps of each of the flip-chips, respectively,

wherein the equivalent conductance of each of the power pins is larger than the corresponding minimum conductance in each of the flip-chips.

14. The method as claimed in claim 9 , further comprising:

determining whether the RDL routing of each of the flip-chips has routing congestion or wire crossings; and

changing the corresponding bump assignment of the flip-chip when it is determined that the RDL routing of the flip-chip has routing congestion or wire crossings.

15. The method as claimed in claim 14 , wherein a total wire-length of the RDL routing is minimized for each of the flip-chips.

16. The method as claimed in claim 9 , further comprising:

modeling the IR constraints according to the RDL routing of each of the flip-chips to prevent IR violations of the bump assignments; and

obtaining the interposer routing according to the modeled IR constraints and the bump assignments of all of the flip-chips.