Target Punch through and scrap

I work as technician in a Singapore semiconductor factory. Here I share my working life as technician.

Lately we have another tool issue, that is deposition uniformity out.

So upon investigation, we suspect there is some other foreign material in the deposition. We decided to vent the chamber and check.

The target upon open out, looks like this, wonder if you observe any abnormality?

Maybe another angle for your referrence to check.

You observe the center of it is a valley shape right?

Yes the problem is the center of target was "eaten" too much too deep, until it finished off all the original material, and expose out the backing plate material. This is different from what we supposed to deposit already.

Product will be scrapped if wrong material is used. Too bad , in this case, all the products wrongly deposited will be all called back and scrapped. Sigh..