Defective die replacement in a die stack
The dies of a stacked die IC are tested and, in response to detection of a defect at one of the dies, the type of defect is identified. If the defect is identified as a defective module repairable at the die itself, a redundant module of the die is used to replace the functionality of the defective module. If the defect is identified as one that is not repairable, a replacement die in the die stack is used to replace the functionality of the defective die.
1. A method comprising:
detecting a first defect in a first die of a plurality of dies arranged in a stacked die integrated circuit; and
in response to detecting the first defect, replacing the first die with a second die of the plurality of dies by activating the second die by setting a first bus address for the second die to correspond to a second bus address for the first die and deactivating the first die.
2. The method of claim 1 , wherein deactivating the first die comprises negating a first active bit at the first die and activating the second die comprises setting a second active bit at the second die.
3. The method of claim 1 , wherein deactivating the first die comprises deactivating the second bus address for the first die.
4. The method of claim 1 , wherein deactivating the first die comprises decoupling power from a module of the first die.
5. The method of claim 1 , wherein deactivating the first die comprises placing an input/output module of the first die in an inactive state.
6. The method of claim 1 , further comprising adding the second die to the plurality of dies in response to identifying the first defect.
7. The method of claim 6 , wherein adding the second die comprises adding the second die using a first solder having a melting point at least 15 degrees Celsius different from a melting point of a second solder used to attach the first die at the plurality of dies.
8. A method, comprising:
detecting a defect at a first die of a plurality of dies arranged in a stacked die integrated circuit;
in response to the defect being a defect of a first type, replacing functionality of a defective module of the first die with functionality of a second module of the first die; and
in response to the defect being a defect of a second type at the first die, replacing the functionality of the first die with functionality of a second die of the plurality of dies by setting a first bus address for the second die to correspond to a second bus address for the first die.
9. The method of claim 8 , wherein replacing the functionality of the defective module comprises asserting a control pin of the first die to indicate an internal repair of the first die.
10. The method of claim 8 , wherein replacing the functionality of the first die with the second die comprises:
negating a control pin of the first die to indicate a non-internal repair of the first die; and
negating a first active bit at the first die and activating setting a second active bit at the second die.
11. The method of claim 10 , wherein replacing the functionality of the first die with the functionality of the second die further comprises decoupling power from a module of the first die.
12. The method of claim 10 , wherein replacing the functionality of the first die with the functionality of the second die further comprises placing an input/output module of the first die in an inactive state.
13. The method of claim 8 , wherein replacing the functionality of the first die with the functionality of the second die further comprises clearing the second bus address for the first die.