Contact-less probe of semiconductor wafers

• US 6,300,785 B1
• Filed: 10/20/1998
• Issued: 10/09/2001
• Est. Priority Date: 10/20/1998
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nowak, Edward J., Cook, Donald J., Tong, Minh H.
• Primary Examiner(s): KARLSEN, ERNEST F
• Application Number:
  US09/175,303
• Time in Patent Office: 1,085 Days
• Field of Search: 324/765, 324/763, 714/733, 714/734
• US Class Current: 324/754.21
• CPC Class Codes: G01R 31/311 of integrated circuits G01R31/31728 takes precedence
• CPC Class Codes: Y10S 136/291 Applications
• CPC Class Codes: Y10S 136/293 Circuits

Abstract

A device, having circuits formed thereon, comprises a circuit including a frequency generator for generating a detectable radio frequency energy when powered and a power generator, coupled to the frequency generator, for generating power when exposed to light.

Claims

1. A device having a built-in contact-less probe for allowing contact-less testing of said device, said probe comprising:

a test circuit including a frequency generator for generating a detectable radio frequency energy when powered, wherein said frequency generator changes a frequency of said radio frequency energy depending upon the presence of defects within said device; and

a power generator, coupled to said frequency generator, for generating power when exposed to light.

2. The device of claim 1, wherein said changes in said frequency of said radio frequency energy comprise detectable characteristics correlating to a level of processing quality of said device.

3. The device as in claim 1, wherein said frequency generator comprises a ring oscillator.

4. The device as in claim 1, wherein said power generator comprises a plurality of diodes.

5. The device as in claim 4, wherein said plurality of diodes are each formed in a separate well and coupled in series for generating voltage when exposed to light.

6. The device as in claim 1, wherein said power generator includes an antenna.

7. The device as in claim 6, wherein said antenna comprises signal wiring connected to said power generator.

8. The device as in claim 1, further comprising a current amplifying device connected to said power generator.

9. The device as in claim 8, wherein said current amplifying device comprises:

a capacitor connected to said power generator and for being charged by said power generator;

a transistor for controlling said capacitor;

a second series of diodes for activating said transistor when exposed to light.

21. The device in claim 1, wherein said frequency generator includes a first generator having a first design and a second generator having a second design, wherein a difference in radio signal frequencies produced by said first generator and said second generator provides a measure of manufacturing quality of said device.

22. The device in claim 21, wherein said first generator includes transistors having gates having a first width and said second generator includes transistors having gates having a second width that is different than said first width.

23. The device in claim 1, wherein said probe includes a capacitor connected to said frequency generator, wherein a charging rate of said capacitor controls said frequency of said radio frequency energy.

24. The device in claim 23, wherein said charging rate provides a measure of manufacturing quality of said device.

10. A system for testing semiconductor chips comprising:

a circuit including a frequency generator for generating a detectable radio frequency energy when powered, wherein said frequency generator changes a frequency of said radio frequency energy depending upon the presence of defects within said device;

a power generator, coupled to said frequency generator, for generating power when exposed to light;

an optical device for generating said light;

a receiver for detecting said radio frequency energy;

an analyzer connected to said receiver for analyzing said radio frequency energy.

11. The system of claim 10, wherein said chances in said frequency of said radio frequency energy comprise detectable characteristics correlating to a level of processing quality of said device.

12. The system as in claim 10, wherein said frequency generator comprises a ring oscillator.

13. The system as in claim 10, wherein said power generator comprises a plurality of diodes.

14. The system as in claim 13, wherein said plurality of diodes are each formed in a separate well and coupled in series for generating voltage when exposed to light.

15. The system as in claim 10, wherein said power generator includes an antenna.

16. The system as in claim 15, wherein said antenna comprises signal wiring connected to said power generator.

17. The system as in claim 10, wherein said optical device comprises a microscope light.

18. The system as in claim 10, wherein said receiver comprises a radio frequency receiver.

19. The system as in claim 10, further comprising a current amplifying device connected to said power generator.

20. The device as in claim 19, wherein said current amplifying device comprises:

a capacitor connected to said power generator and for being charged by said power generator;

a transistor for controlling said capacitor;

a second series of diodes for activating said transistor when exposed to light.

25. The device in claim 10, wherein said frequency generator includes a first generator having a first design and a second generator having a second design, wherein a difference in radio signal frequencies produced by said first generator and said second generator provides a measure of manufacturing quality of said device.

26. The device in claim 25, wherein said first generator includes transistors having gates having a first width and said second generator includes transistors having gates having a second width that is different than said first width.

27. The device in claim 10, wherein said circuit includes a capacitor connected to said frequency generator, wherein a charging rate of said capacitor controls said frequency of said radio frequency energy.

28. The device in claim 27, wherein said charging rate provides a measure of manufacturing quality of said device.