Method for laser scanning flip-chip integrated circuits

• US 6,375,347 B1
• Filed: 09/05/2000
• Issued: 04/23/2002
• Est. Priority Date: 11/04/1998
• Status: Expired due to Fees

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Bruce, Michael R., Bruce, Victoria J.
• Primary Examiner(s): Gutierrez, Diego
• Assistant Examiner(s): PRUCHNIC, STANLEY J
• Application Number:
  US09/654,823
• Time in Patent Office: 595 Days
• Field of Search: 374/161, 374/130, 374/120, 374/4-7, 374/137, 438/14, 438/15, 438/16, 438/17, 324/765, 324/501, 324/555, 324/537, 324/752, 356/237.1
• US Class Current: 374/5
• CPC Class Codes: G01J 5/0003 for sensing the radiant heat transfer of samples, e.g. emittance meter
• CPC Class Codes: G01K 11/00 Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
• CPC Class Codes: G01N 25/72 Investigating presence of flaws

Abstract

Methods for analyzing temperature characteristics of an integrated circuit. In one embodiment, a beam of laser light is directed at the back side of an integrated circuit. The intensity level of laser light reflected from the integrated circuit is measured and compared to a reference intensity level. The magnitude of the difference between the reference intensity level and the intensity level of the reflected laser light is indicative of a temperature characteristic of the integrated circuit.

Claims

1. A method for analyzing temperature characteristics of an integrated circuit having a back side opposite a circuit side including suspect target circuitry, comprising:

directing a beam of laser light at the back side of the integrated circuit;

using a test controller to power the integrated circuit with a source providing nonconstant current and nonconstant voltage and to exercise the suspect circuitry while the beam is being directed at the back side;

in response to the steps of directing a beam of laser light and using a test controller to exercise the suspect circuitry, measuring at least one parameter responding to the suspect circuitry; and

comparing said at least one parameter with a reference level, whereby a magnitude of difference between the reference level and said at least one parameter is indicative of a temperature characteristic of the suspect circuitry.

2. The method of claim 1, wherein the laser light is generated from a near-infrared laser.

3. The method of claim 1, wherein an angle of incidence of the beam of laser light with the integrated circuit is substantially perpendicular.

4. The method of claim 1, wherein an angle of incidence of the beam of laser light with the integrated circuit is between about 30°

and 45°

.

5. An arrangement for analyzing temperature characteristics of an integrated circuit having a back side opposite a circuit side including suspect target circuitry, comprising:

means for directing a beam of laser light at the back side of the integrated circuit;

a test controller adapted to power the intergrated circuit with a source providing nonconstant current and nonconstant voltage and to exercise the suspect circuitry while the beam is being directed at the back side;

means, responsive to said directing means and the test controller, for measuring at least one parameter responding to the suspect circuitry; and

means for comparing said at least one parameter with a reference level, whereby a magnitude of difference between the reference level and said at least one parameter is indicative of a temperature characteristic of the suspect circuritry.

6. The arrangement of claim 5, wherein the laser light is generated from a near-infrared laser.

7. The arrangement of claim 5, wherein an angle of incidence of the beam of laser light with the integrated circuit is substantially perpendicular.

8. The arrangement of claim 5,wherein an angle of incidence of the beam of laser light with the integrated circuit is between about 30°

and 45°

.

9. An arrangement for analyzing temperature characteristics of an integrated circuit having a back side opposite a circuit side including suspect target circuitry, comprising:

a laser tool adapted to direct a beam of laser light at the back side of the integrated circuit;

a test controller adapted to power the integrated circuit with a source providing nonconstant current and nonconstant voltage and to exercise the suspect circuitry with input data while the beam is being directed at the back side;

the test controller including a detector, responsive to the laser tool and the test controller, adapted to measure at least one parameter responding to the suspect circuitry; and

a control unit adapted to compare said at least one parameter with a reference level, whereby a magnitude of difference between the reference level and said at least one parameter is indicative of a temperature characteristic of the suspect circuitry.

10. The arrangement of claim 9, wherein the control unit is coupled to the detector and the laser tool.

11. The arrangement of claim 9, further including a deflecting unit in the beam of the laser light.

12. The arrangement of claim 11, wherein the control unit is responsive to the deflecting unit.

13. The arrangement of claim 9, wherein the laser tool and the test controller are adapted to scan the back side when the integrated circuit is operating in a condition that includes a failure mode of the suspect target circuitry.

14. A method for analyzing temperature characteristics of an integrated circuit having a back side opposite a circuit side including suspect target circuitry, comprising:

directing a beam of laser light at the back side of the integrated circuit with an angle of incidence of the beam of laser light with the integrated circuit being substantially nonperpendicular;

using a test controller to power the integrated circuit and to exercise the suspect circuitry while the beam is being directed at the back side;

in response to the steps of directing a beam of laser light and using a test controller to exercise the suspect circuitry, measuring at least one parameter responding to the suspect circuitry; and

comparing said at least one parameter with a reference level, whereby a magnitude of difference between the reference level and said at least one parameter is indicative of a temperature characteristic of the suspect circuitry.

15. The method of claim 14, wherein the angle of incidence of the beam of laser light with the integrated circuit is between about 30°

and 45°

.

16. The method of claim 14, wherein test controller is further adapted to power the integrated circuit using a source providing nonconstant current and nonconstant voltage.

17. An arrangement for analyzing temperature characteristics of an integrated circuit having a back side opposite a circuit side including suspect target circuitry, comprising:

means for directing a beam of laser light at the back side of the integrated circuit with an angle of incidence of the beam of laser light with the integrated circuit being substantially nonperpendicular;

a test controller adapted to power the integrated circuit and to exercise the suspect circuitry while the beam is being directed at the back side;

means, responsive to said directing means and the test controller, for measuring at least one parameter responding to the suspect circuitry; and

means for comparing said at least one parameter with a reference level, whereby a magnitude of difference between the reference level and said at least one parameter is indicative of a temperature characteristic of the suspect circuitry.

18. The arrangement of claim 17, wherein the angle of incidence of the beam of laser light with the integrated circuit is between about 30°

and 45°

.

19. The arrangement of claim 17, wherein test controller is further adapted to power the integrated circuit using a source providing nonconstant current and nonconstant voltage.