Gold inside chips (black, flatpacks - not CPU)

[patnor1011]

Well I am not skilled enough to make videos, that is why I just put pictures there. Well to be fair I have to say that I did this but some credit should go to Rusty and NoIdea gents who pretty much started it and I discussed on how to do it with Sucho. So I take it as collective effort. Anyone who will use this can contribute with his observations and we will perfect it in no time.

 

[Geo]

I'm not sure whether it will help, but I've had an idea (boy did it give me a headache) :lol: . Since HCl and nitrate is relatively inexpensive, I was considering using poor man's AR to remove the legs from the ICs before incineration. This would quickly remove a lot of unwanted metal before the process even begins and because you're incinerating anyway there's no problem moving to AP to remove more unwanted metal after incineration. Just trying to nail down a process that can be the quickest and least troublesome.

 

[philddreamer]

Geo, I think that would add more time to the process & create for me more chemical waste... & there's a lot more unwanted metal inside.

 

[Claudie]

Phil,

Is that a stainless steel wash basin that you are using to hold the IC packages?

 

[philddreamer]

Hi Claudie!

No, it's a porcelain coated pan. After putting the chips in my S.S. I noticed the chips were stacked up in it, so I decide to use something with more flat area. It worked good. I tried the other day the S.S. bowl, & I was right, the chips take longer to incinerate. I like to spread them out on a flat surface with more area.

Phil

 

[gmiller]

"Geo" said: "Since HCl and nitrate is relatively inexpensive, I was considering using poor man's AR to remove the legs from the ICs before incineration. This would quickly remove a lot of unwanted metal before the process even begins and because you're incinerating anyway there's no problem moving to AP to remove more unwanted metal after incineration. Just trying to nail down a process that can be the quickest and least troublesome."

Why bother with AR to remove your unwanted metals, when HCl alone will do the same thing with less expense? You can stll move on to AP straight from HCl since HCl is a componant of AP.

Just my thoughts on the process.

BTW a great post, thanks

Gary

 

[patnor1011]

Time-wise AR is faster than HCl. Since I am pedant and have all the time in a world for my hobby I cut them by stainless blade - the one used for carpets. It is quick and remove unwanted metal too. :lol:

 

[Geo]

Gary,

When I'm dealing with many pounds of material, I like to remove as much base metal as quickly as possible. the legs on the IC chips is a large percentage of the base metal weight. By using a small amount of HCl and sodium nitrate, I can remove almost half of my base metal weight in a matter of a couple of hours. Then when I incinerate the chips it removes all traces of the nitrates and leaves me with just the metal inside the chip to deal with. About 90% of the chips I have may have tin plated legs but have gold plating inside the plastic body excluding bonding wires and pad. Everyone has their own style and preferences with which process works for them and for me, well, this keeps my solution nice and clean with a lot less copper and tin to deal with.

 

[patnor1011]

We are looking for method which will make process faster and eliminate some hazards. I do have a lot of time so some of my methods are suitable for smaller lots. I did say few times that I cut chips off board with blade which reduce unwanted metal to some extent but it is time consuming. Not applicable for older chips with less legs which are thicker unless you are some kind of bodybuilder
I was thinking that maybe heatgun for desoldering them and then they can be placed to some type of SSN leach to cut on chemicals cost - salt is not that expensive. Maybe saturated salt solution with HNO₃ ratio 10:1 and legs will be dissolved with values inside chip untouched. Then rinse and pyrolysis-incineration. I will do some tests with different SSN leach ratios next week.

 

[acpeacemaker]

I was going to post this a while back and didn't get the chance. It's somewhat crude but does work. Made from concrete with a couple of 3 gallon buckets. The outer wall sits on shims to allow the coal to breathe. Then the pot sits directly on the coals leaving a little over a half inch gap around the rim to breathe. Coals are put in the pot as well. I haven't ever really had any problems with plastic smells and I live 3 houses down from a fire chief. Anyways, I just wanted to say thank you to the people like Pat and Sam, and many others that have inspired me. -Andrew

 

[Dude4ever]

Hi patnor, just a little question to your guide, I've read this post and your PDF guide, but I could not find if you just pour out the water from the washes or doing something else, leaving the heavier gold at the bottom? I mean, it is a pretty grey/dark solution, so how is it you control that you don't pour out gold with the washes? Sorry if it's adressed here somewhere, I could have missed it, but nice if you could explain the washes a little more

 

[patnor1011]

Most of gold in there is in form of bonding wires. Say over 90%. Rest is as plating on pins and plating on silicon chip. I think that there may be some super fine flakes or powder from crushed silicon chip and they may float or take too long to settle but that may be so tiny amount not worth chasing so yes, I do pour that water away as it is just what it is - dirty stained water. If you adjust flow correctly then you can be sure that you pour off water and dirt only and wires and small flakes stays at bottom. That is like first cleaning, second is bit harder, your panning technique must be pretty good as single pieces of wire are barely visible, only when accumulated and you want to separate them from metallic pins.

 

[Dude4ever]

Cool, thanks
So I should wait a couple of minutes for the gold to settle between washes? What if you use a second container that you pour the washes into, and let that stand over night, and then siphon off much of the excess water and wash it like before, maybe you can find some more gold without too much effort?

 

[patnor1011]

I dont know, purpose of washing is to get rid of ashes so if you leave it stand all night it just settle down and you did not washed anything. I am thinking about using blue bowl for washing. Particles of gold chipped away from silicon wafer are minuscule to be worth chasing for. I am happy with gold from bonding wires and plating on pins from inside.

 

[Scraprat]

Great information, can't wait to try my hand at incinerating some chips.

Will this method work on connectors i.e. ram slots, ribbon cable on mother boards?

 

[qst42know]

Chips are low in polymers and high in fillers. Other plastic composites such as mother boards and connectors will not burn so tamely. If you start a board on fire it will get ugly fast. Loads of soot and toxins.

 

[crow king]

I just weighed 8oz of gold cornered flatpacks and put them into a HCl wash to remove some of the solder on the bottom. I noticed no reaction and intend to now incinerate. Is the solder on there something to be wary of?

I also had a handful of gold cornered flatpacks that had monolithics attached to them, as well as a metal heat sink or such attached, do you know what metal this is? Do you process all these together or separate? Is there any contaminating metals that frequent these parts that I should watch for?

 

[maynman1751]

I just weighed 8oz of gold cornered flatpacks and put them into a HCl wash to remove some of the solder on the bottom. I noticed no reaction and intend to now incinerate. Is the solder on there something to be wary of?

I also had a handfull of gold cornered flatpacks that had monolithics attached to them, as well as a metal heat sink or such attached, do you know what metal this is? Do you process all these together or separate? Is there any contaminating metals that frequent these parts that I should watch for?

Heat your solution some. It will dissolve the solder right off!
Flatpacks with monolithics and heatsinks ????? Are you sure they are not CPUs? Post a pic.

 

[patnor1011]

He is right, I found quite few of them it is aluminium round piece inside that black plastic part. I have no problem with them as it is easy to separate that after chip is incinerated/pyrolysed.

The ones with square heatsink attached - well you can detach that with some heat applied or use chisel or knife.

*edited - pictures attached

 

[maynman1751]

Patnor! Do you consider the one with the square heatsink a flatpack? I was under the impression that real flatpacks were like n/s bridge chips. Isn't the square heatsink one some sort of processor? But then again, I suppose the n/s bridge are processors of a sort too!
I haven't yet run across one like that ATI.