System and method for electronic testing of partially processed devices
View Patent ↗Systems and methods are provided for testing partially completed three-dimensional ICs. Example methods may incorporate one or more of the following features: design for testing (DFT); design for partial wafer test; design for partial probing; partial IC probecards; partial IC test equipment; partial IC quality determinations; partial IC test optimization; and partial test optimization. Other aspects may also be included. Systems and methods incorporating these features to test partially completed three-dimensional ICs may result in saved time and effort, and less scraped material, as the partial device is not built any further when a bad partial device is detected. This results in lower costs and higher yield.
1. A partially assembled three-dimensional integrated circuit (3DIC), comprising: a plurality of individual integrated circuits (IC) that are stacked on each other, and one or more design for testing means (DFT means) applied to one or more of the plurality of individual ICs, the DFT means being adapted to permit the 3DIC to be tested while it is partially assembled.
2. The 3DIC of claim 1 , where the DFT means comprises means for performing boundary scans of one or more of the plurality of individual ICs.
3. The 3DIC of claim 1 , where the DFT means comprises an interconnect, the interconnect electronically linking two or more of the plurality of individual ICs, and adapted to be accessible for testing when the 3DIC is partially assembled.
4. The 3DIC of claim 1 , where the DFT means comprises built in self test (BIST) circuitry.
5. The 3DIC of claim 4 , where the BIST circuitry is in electrical communication with one or more of the plurality of individual ICs through silicon vias (TSVs).
6. The 3DIC of claim 4 , where the BIST circuitry comprises one or more controllers adapted to control the BIST circuitry.
7. The 3DIC of claim 1 , where the DFT means comprises means for testing through a scan chain of circuits.
8. The 3DIC of claim 1 , where the DFT means comprises oscillation interconnect testing circuitry.
9. A method of testing a partially assembled three-dimensional integrated circuit (3DIC) comprising a plurality of individual integrated circuits (IC) that are stacked on each other, the method comprising: applying one or more design for testing means (DFT means) to one or more of the plurality of individual ICs, and testing the 3DIC while it is partially assembled.
10. The method of claim 9 , where the DFT means comprises means for performing boundary scans of one or more of the plurality of individual ICs.
11. The method of claim 9 , where the DFT means comprises an interconnect, the interconnect electronically linking two or more of the plurality of individual ICs, and adapted to be accessible for testing when the 3DIC is partially assembled.
12. The method of claim 9 , where the DFT means comprises built in self test (BIST) circuitry.
13. The method of claim 12 , where the BIST circuitry is in electrical communication with one or more of the plurality of individual ICs through silicon vias (TSVs).
14. The method of claim 12 , where the BIST circuitry comprises one or more controllers adapted to control the BIST circuitry.
15. The method of claim 9 , where the DFT means comprises means for testing through a scan chain of circuits.
16. The method of claim 9 , where the DFT means comprises oscillation interconnect testing circuitry.
17. A method of testing a partially assembled three-dimensional integrated circuit (3DIC) comprising a plurality of individual integrated circuits (IC) that are stacked on each other, the method comprising: selecting one or more stages of completion at which the 3DIC should be tested by performing one or more design for partial probing steps (DFPP steps), and testing the 3DIC at those one or more stages of completion.
18. The method of claim 17 , where the DFPP steps include steps for optimizing based on historical data.
19. The method of claim 18 , where the steps for optimizing based on historical data includes studying defectivity data.
20. The method of claim 17 , where the DFPP steps include simulation of testing using statistical techniques.
21. The method of claim 20 , where the simulation of testing is based at least in part on the design of the 3DIC.