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Help-Wire Bonding Defects Analysis After Encapsulation

Chi-Ting Chen

#13398

Help-Wire Bonding Defects Analysis After Encapsulation | 26 November, 1998

I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure is caused by die, die attached paste, wire bonding, encapsulant, popcorn, or thermal mismatch? Could someone please list some of theanalysis methods and providers?

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Earl Moon

#13399

Re: Help-Wire Bonding Defects Analysis After Encapsulation | 26 November, 1998

| I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure is caused by die, die attached paste, wire bonding, encapsulant, popcorn, or thermal mismatch? Could someone please list some of theanalysis methods and providers? | X-RAY

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Chi-Ting Chen

#13400

Re: Help-Wire Bonding Defects Analysis After Encapsulation | 27 November, 1998

| | I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure is caused by die, die attached paste, wire bonding, encapsulant, popcorn, or thermal mismatch? Could someone please list some of theanalysis methods and providers? | | | X-RAY | However, an X-ray machine provider told me that only gold wires are visible. X-ray would penetrate Al wires and leave no image of Al wire.

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Chi-Ting Chen

#13401

Re: Help-Wire Bonding Defects Analysis After Encapsulation | 27 November, 1998

| | I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure is caused by die, die attached paste, wire bonding, encapsulant, popcorn, or thermal mismatch? Could someone please list some of theanalysis methods and providers? | | | X-RAY | However, an X-ray machine provider told me that only gold wires are visible. X-ray would penetrate Al wires and leave no image of Al wire.

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Earl Moon

#13402

Re: Help-Wire Bonding Defects Analysis After Encapsulation | 27 November, 1998

| | | I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure is caused by die, die attached paste, wire bonding, encapsulant, popcorn, or thermal mismatch? Could someone please list some of theanalysis methods and providers? | | | | | X-RAY | | | However, an X-ray machine provider told me that only gold wires are visible. X-ray would penetrate Al wires and leave no image of Al wire. | You've taught me something. Thank you. However, x-ray might show the bond termination and whether there is separation. I guess I believe the machine provider, but I'd still try as I know of no other way short of attempting to remove the encapsulation, and you know what that probabley will do. Check the boys and girls on the IPC ChipNet part of the TechNet.

Earl Moon

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Russ M

#13403

Re: Help-Wire Bonding Defects Analysis After Encapsulation | 3 December, 1998

| | | | I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure is caused by die, die attached paste, wire bonding, encapsulant, popcorn, or thermal mismatch? Could someone please list some of theanalysis methods and providers? | | | | | | | X-RAY | | | | | However, an X-ray machine provider told me that only gold wires are visible. X-ray would penetrate Al wires and leave no image of Al wire. | | | You've taught me something. Thank you. However, x-ray might show the bond termination and whether there is separation. I guess I believe the machine provider, but I'd still try as I know of no other way short of attempting to remove the encapsulation, and you know what that probabley will do. Check the boys and girls on the IPC ChipNet part of the TechNet. | | Earl Moon | To "see" Aluminum wires in the epoxy by X-Ray is possible. Glenbrook Technologies machines are capable of doing this. Normally, only gold wires are visible by X-Ray. But, I saw a demonstration of the Glenbrook equipment looking at Al wires and it does work. They are the only company I am familiar with that has that capability. They have a web site and are located in New Jersey. Contact them for your inspection needs.

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