Method for testing an electric circuit

1. A method for testing an electric circuit, comprising:

a) applying a first data signal to a first electric circuit, the first electric circuit produced by a first process sequence;

b) generating a signal indicative if said first electric circuit is defective by comparing a second data signal with a data signal generated by said first electric circuit in response to said first data signal;

c) producing a second electric circuit by a predetermined second process sequence which includes incorporating intentionally at least one predetermined defect structure into said second electric circuit;

d) applying the first data signal to said second electric circuit and comparing the second data signal with a data signal generated by said second electric circuit in response to said first data signal;

e) repeatedly modifying the first data signal and applying said modified first data signal to said second electric circuit until said comparison indicates a defect of said second electric circuit; and

f) storing information about the modified first data signal which results in said indication about the defect of said second electric circuit.

2. The method of claim 1 , further comprising

g) producing a third electric circuit by a predetermined third process sequence which includes incorporating intentionally at least a second predetermined defect structure into said third electric circuit;

h) applying the first data signal to said third electric circuit and comparing the second data signal with a data signal generated by said third electric circuit in response to said first data signal;

i) repeatedly further modifying the first data signal and applying said further modified first data signal to said third electric circuit until said comparison indicates a defect of said third electric circuit; and

f) storing information about the further modified first data signal which results in said indication about the defect of said third electric circuit.

3. The method of claim 1 , wherein said first electric circuit and said second electric circuit comprise memory modules.

4. The method of claim 1 , wherein said first and second predetermined process sequences comprise at least one lithography step.

5. The method of claim 1 , wherein said first data signal includes at least one variable parameter.

6. The method of claim 5 , wherein said variable parameter is at least one of a frequency, a voltage level or a current level of said data signal.

7. The method of claim 1 , further comprising repeating step b) while varying a temperature of said first electric circuit.

8. The method of claim 1 , wherein step c) further comprises incorporating said least one predetermined defect structure into said second electric circuit using a mask device during a lithography process.

9. The method of claim 8 , wherein said defect structure is a defect in a conduction track of the second electric circuit.

10. The method of claim 1 , wherein step c) further comprises incorporating a plurality of defect structures having different sizes into the second electric circuit.

11. The method of claim 1 , wherein said first electric circuit is free of intentionally incorporated defect structures.

12. The method of claim 1 , wherein said second electric circuit comprises a conduction track and step c) further comprises incorporating said at least one defect structure as a hole in said conduction track.

13. The method of claim 1 , wherein said second electric circuit comprises a conduction plane and and step c) further comprises incorporating said at least one defect structure as a hole in said conduction plane.

14. The method of claim 1 , wherein said second electric circuit comprises a plurality of conduction tracks and step c) further comprises incorporating said at least one defect structure as a bridge between at least two of said conduction tracks.

15. The method of claim 1 , wherein said second electric circuit comprises at least one conduction track and at least one conduction plane and step c) further comprises incorporating said at least one defect structure as a bridge between said conduction track and said conduction plane.

16. The method of claim 1 , wherein step c) further comprises incorporating said at least one defect structure such that said defect structure has a density in a range of 0 to 2.5 per square millimeter.

17. The method of claim 1 , wherein step c) further comprises incorporating said at least one defect structure such that said defect structure has a density in a range of 0.5 to 5.0 micrometers.

18. The method of claim 1 , wherein the first data signal is the second data signal.

19. A method for testing an electric circuit, comprising:

a) applying a first data signal to a first electric circuit, the first electric circuit produced by a first process sequence;

b) generating a signal indicative if said first electric circuit is defective by comparing a second data signal with a data signal generated by said first electric circuit in response to said first data signal;

c) providing a second electric circuit generated by a predetermined second process sequence which includes incorporating intentionally at least one predetermined defect structure into said second electric circuit;

d) determining a third data signal, the third data signal configured such that when applied to said second electric circuit, a comparison of the second data signal with a data signal generated by said second electric circuit in response to said third data signal indicates a defect of said second electric circuit;

and e) storing information about the third data signal which results in said indication about the defect of said second electric circuit.

20. The method of claim 19 , wherein the first data signal and the second data signal comprise the same data stream.