Interconnect reliability structures

Patent metadata

Field	Value
Publication number	US-9817063-B2
Application number	US-201615048704-A
Country	US
Kind code	B2
Filing date	Feb 19, 2016
Priority date	Feb 19, 2016
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

The present disclosure relates to semiconductor structures and, more particularly, to interconnect reliability structures and methods of manufacture. The structure includes: a plurality of resistors; and a voltmeter configured to sense a relative difference in resistance of the plurality of resistors indicative of at least one of a via-depletion and line-depletion.

First claim

What is claimed:

1. A structure, comprising:
a plurality of resistors; and
a voltmeter configured to sense a relative difference in resistance of the plurality of resistors indicative of at least one of a via-depletion and line-depletion,
wherein each of the plurality of resistors comprise via chain structures which comprise:
a single via interconnect on one side of a wiring layer of a dual damascene structure, and
a plurality of via interconnects on another side of the wiring layer, and

each of the plurality of via interconnects are in direct contact with each other and an upper wiring layer.

2. The structure of claim 1 , wherein the plurality of resistors comprise a first set of resistors having a first polarity and a second set of resistors having a second polarity.

3. The structure of claim 2 , wherein the first set of resistors and the second set of resistors form a Wheatstone bridge.

4. The structure of claim 2 , wherein the first set of resistors is configured to sense via depletion caused by electromigration and the second set of resistors is configured to sense line depletion caused by electromigration.

5. The structure of claim 4 , wherein:
the plurality of resistors each comprise the dual damascene structure and an interconnect via structure in direct electrical connection with the wiring layer of the dual damascene structure;
a liner material between the wiring layer of the dual damascene structure and the interconnect via structure; and
a junction of the wiring layer and a via interconnect structure of the dual damascene structure is devoid of the liner material.

6. The structure of claim 5 , wherein the second set of resistors are on opposing sides of the voltmeter and are located such that electrons flow from the interconnect via structure into the dual damascene structure.

7. The structure of claim 5 , wherein the first set of resistors are on opposing sides of the voltmeter and are located such that electrons flow from the dual damascene structure into the interconnect via structure.

8. The structure of claim 1 , wherein the plurality of via interconnects on the other side of the wiring layer has a lower resistance than the single via interconnect.

9. The structure of claim 1 , wherein the plurality of resistors are connected to a wiring structure which has a line width greater than a line width of each of the resistors.

10. The structure of claim 1 , wherein the via chain structures further comprise an interconnect reliability structure.

11. The structure of claim 10 , wherein a liner is provided at a junction of a lower wiring layer and the single via interconnect and at a junction of the lower wiring layer and the plurality of via interconnects.

12. A structure, comprising:
a first set of resistors having a first polarity;
a second set of resistors having a second polarity; and
a voltmeter configured to sense a relative difference in resistance between the first set of resistors and the second set of resistors,
wherein each resistor of the first set of resistors and the second set of resistors comprise via chain structures which comprise:
a single via interconnect on one side of a wiring layer of a dual damascene structure, and
a plurality of via interconnects on another side of the wiring layer, and

each of the plurality of via interconnects are in direct contact with each other and an upper wiring layer.

13. The structure of claim 12 , wherein the first set of resistors and the second set of resistors form a Wheatstone bridge.

14. The structure of claim 13 , wherein the first set of resistors comprise a via depletion electromigration structure and the second set of resistors comprise a line depletion electromigration structure.

15. The structure of claim 14 , wherein the second set of resistors are on opposing sides of the voltmeter and are located such that electrons flow from an interconnect via structure into the dual damascene structure.

16. The structure of claim 14 , wherein the first set of resistors are on opposing sides of the voltmeter and are located such that electrons flow from the dual damascene structure into an interconnect via structure.

17. The structure of claim 12 , wherein plurality of via interconnects on the other side of the wiring layer has a lower resistance than the single via interconnect.

18. The structure of claim 12 , wherein the plurality of resistors are connected to a wiring structure which has a line width greater than a line width of each of the resistors.

19. A method, comprising:
continuously monitoring a voltage V WB during in-line current ramp based on a resistive difference between a first resistor and a second resistor in a Wheatstone bridge;
determining a statistically significant shift direction of V WB shift in real time during the in-line current ramp;
an increase of the shift direction in V WB is indicative of a line depletion failure; and
a decrease of the shift direction in V WB is indicative of a via depletion failure.

20. The method of claim 19 , wherein:
no statistically significant shift direction in V WB is indicative of no electromigration defects being found.

Assignees

• Globalfoundries Inc

Inventors

• Wang Ping-Chuan
• Kim Andrew T
• Filippi Ronald G

Classifications

• H10P74/277

  Circuits for electrically characterising or monitoring manufacturing processes, e.g. circuits in tested chips or circuits in testing wafers · CPC title

• H10W20/42

  Vias, e.g. via plugs · CPC title

• H10P74/207

  Electrical properties, e.g. testing or measuring of resistance, deep levels or capacitance-voltage characteristics · CPC title

• G01R31/2858 Primary

  Measuring of material aspects, e.g. electro-migration [EM], hot carrier injection · CPC title

• H01L23/5226

  Electricity · mapped topic