Apparatus and Method for Testing Electric Conductors

• US 20150077151A1
• Filed: 09/13/2013
• Published: 03/19/2015
• Est. Priority Date: 09/13/2013
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Nelhiebel, Michael, Fanic, Petar, Zagar, Bernhard, Osterloh, Achim
• Granted Patent: US 9,523,729 B2
• Time in Patent Office: Days
• US Class Current: 324/754.29
• CPC Class Codes: G01R 1/07 Non contact-making probes
• CPC Class Codes: G01R 15/205 using magneto-resistance devices, e.g. field plates
• CPC Class Codes: G01R 15/207 Constructional details independent of the type of device used
• CPC Class Codes: G01R 31/2853 Electrical testing of internal connections or -isolation, e.g. latch-up or chip-to-lead connections G01R31/31717 takes precedence; test of chip-to-PCB or lead-to-PCB connections G01R31/66
• CPC Class Codes: G01R 31/58 Testing of lines, cables or conductors testing of electric windings G01R31/72

Abstract

A testing device for testing electric conductors includes a probe configured to measure a magnetic field caused by a current in one or more electric conductors of a device under testing (DUT). An output generator configured to generate output data, wherein the output data depend on the measured magnetic field.

Claims

1. A testing device for testing electric conductors, comprising:

a probe configured to measure a magnetic field caused by a current in one or more electric conductors of a device under testing (DUT); and

an output generator configured to generate output data, wherein the output data depend on the measured magnetic field.

2. The device according to claim 1, wherein the testing device is configured to test more than one DUT simultaneously.

3. The device according to claim 1, further comprising:

a positioning stage configured to arrange the probe in predefined positions over the electric conductors of the DUT.

4. The device according to claim 1, further comprising:

a memory configured to store reference data of reference magnetic fields; and

a comparator configured to compare the output data with the reference data.

5. The device according to claim 1, wherein the output data comprise data about the spatial structure of the magnetic field in at least one dimension.

6. The device according to claim 1, wherein the probe comprises one or more giant magneto resistance elements.

7. The device according to claim 1, wherein the output generator is configured to generate output data when the DUT comprises one or more defective electric conductors and to generate different output data when the DUT comprises no defective conductors.

8. The device according to claim 1, wherein the output generator is configured to generate output data when the DUT comprises a specific defective electric conductor and to generate different data output from a DUT wherein the specific electric conductor is not defective.

9. The device according to claim 1, wherein the probe comprises a single axis magnetic field sensor.

10. The device according to claim 1, wherein the probe comprises a triple axis magnetic field sensor.

11. A method of testing electric conductors, the method comprising:

providing a device under testing (DUT), the DUT comprising one or more first electric conductors;

providing a testing device comprising a first probe configured to measure a first magnetic field caused by an electric current in the one or more first electric conductors;

applying a voltage to the DUT such that an electric current may flow through the one or more first electric conductors; and

measuring the first magnetic field.

12. The method according to claim 11, further comprising:

providing a reference device, the reference device comprising one or more second electric conductors;

providing a second probe configured to measure a second magnetic field caused by an electric current in the one or more second electric conductors;

applying a voltage to the reference device such that an electric current may flow through the one or more second electric conductors;

measuring a second magnetic field caused by the electric current in the one or more second electric conductors; and

generating a data output by subtracting measurement data of the second magnetic field from measurement data of the first magnetic field.

13. The method according to claim 12, further comprising:

comparing the data output to some reference data; and

deciding if the DUT meets a certain criterion based on the comparison.

14. The method according to claim 11, further comprising:

producing a data output in the testing device, wherein the data output depends on the measured magnetic field; and

comparing the output with some reference data.

15. The method according to claim 11, wherein the DUT is a semiconductor device and the one or more first electric conductors are at least one of:

bonding wires, ball grid arrays, solder bumps, solder clips and die attach.

16. The method according to claim 11, further comprising generating data output in the testing device from a DUT comprising one or more defective conductors and generating different data output from a DUT comprising no defective conductors.

17. The method according to claim 11, further comprising generating data output in the testing device from a DUT comprising a specific defective electric conductor and generating different data output from a DUT wherein the specific electric conductor is not defective.

18. The method according to claim 11, further comprising:

comparing the magnetic field measured at different points above the DUT.

19. A method for dividing devices into groups comprising:

measuring a magnetic field above the devices;

deciding for each of the devices if a criterion is met based on the measurement; and

dividing the devices into groups of devices based on the decision.

20. The method according to claim 19, wherein deciding if the criterion is met comprises comparing the measurement of the magnetic field with some reference data.