Bare die soldering

Yang

Hi,

I am a student from University of Tennessee, Knoxville. Recently, I am trying to test a bare die. However, I find myself in trouble with the soldering of the SiC dies. The finish of source and gate pads are aluminum, which is hard for me to solder in lab. Do you guys have some ideas on how to solder them?

Thanks,
Yang

Forum_Moderator

Thank you for your post, it has been approved and we will respond as soon as possible.

DHofmann

Hi Yang,

what kind of trouble do you face?

Bare dies are not supposed to soldered by hand. Common source attaches are bond wires or clips.

In case of manual hand soldering, there is a high risk of damaging the die.

However, you may use a solder material that is available in a preform. Then solder a metal clip on top.

Yang

Hi,

Thanks for your kind response. The finish of source and gate pads are Al, which cannot be soldered. Do you provide bare dies with other finishes on gate and source pads?

What is solder material available in a perform? Could you explain more about this? Thanks!

DHofmann

Hi,

suggested alloy for aluminum alloy soldering is 91/9 tin. Zinc bonds with aluminum. Another common alloy suggested for aluminum is 96.5/3.5 tin.

For an electrical contact, its works.

Yang

Hi,

These soldering is used with extra flux, which is usually acid. Would the acid damage the bare die, as the finish of aluminum is pretty thin.

Additionally, could you help me check whether Wolfspeed provide customized bare dies with other finishes on gate and source pads?

Thanks

DHofmann

I consider that you do not need reliability since you manually process the die. Therefore, the flux material does not damage the die for your test purposes.

We do not offer a customized finish for manual hand soldering.

Would you mind providing more information on what you need to do?

We can also take the conversation offline.

Yang

Hi,

I want to design and fabricate a power module in the lab. Can you provide your email? We can communicate with emails.

DHofmann

Let me contact you to continue the discussion

TBhatia

Hi, I hope that this answered your question. I will close this discussion for now but if you have a follow up question, please "Start a New Discussion" and we would be glad to support you further.