# Small BGA chip yield



## kjavanb123 (Nov 30, 2020)

Hi

I had about 11 pieces of this small BGA chip, which most of the time along with its bigger ones are the highest yield of IC chips. 

Again, since I am so lucky I get the ones that had zero nada gram of gold instead only copper bond wires. 

Here is the chip I processed there were 10 more that I did all together



Here is the interior after removing the black epoxy all bond wires are copper



This was a toll refine so, not all BGA chips are the same and have gold. A test always required.


----------



## patnor1011 (Dec 2, 2020)

Are you sure it is copper? Gold wires sometimes get discolored if incineration is not complete. 
That being said you are also correct some of these IC do not have just gold wires. I once processed some of this type BGA iC which came from TV sets and if I remember correctly yield was very disappointing I am sure I posted correct number and have it buried in some notes but it was something about a gram from a kilo instead of 5+ expected. It was predominantly 2 types of IC so it was obvious that one type had some gold other had nothing.


----------



## kjavanb123 (Dec 2, 2020)

patnor1011 said:


> Are you sure it is copper? Gold wires sometimes get discolored if incineration is not complete.
> That being said you are also correct some of these IC do not have just gold wires. I once processed some of this type BGA iC which came from TV sets and if I remember correctly yield was very disappointing I am sure I posted correct number and have it buried in some notes but it was something about a gram from a kilo instead of 5+ expected. It was predominantly 2 types of IC so it was obvious that one type had some gold other had nothing.



Hi
Pretty positive those bond wires are copper. I used a "process" that dissolves the black epoxy and leaves the interior structure. 

I also once processed ceramic 486 CPUs 10 pieces yielded 0.1g.

So not two ewaste components can yield the same.


----------



## patnor1011 (Dec 2, 2020)

If you hit substrate with acid then wires will be discolored. Mainly because not all substrate was dissolved. But it is easy to figure out if wire is copper or not - couple ml of nitric will solve mystery quite fast.


----------

