My results of specific types of IC chips, flatpacks and BGA

[anachronism]

James

A cement mixer with varied steel balls in it works wonders. :lol: :lol:

Nick and I call ours the RVEC - sounds so much better than cement mixer.... (Rotary Value Enhancement Concentrator)

For years I refused to go near one.

 

[rickzeien]

James

A cement mixer with varied steel balls in it works wonders. [emoji38] [emoji38]

Nick and I call ours the RVEC - sounds so much better than cement mixer.... (Rotary Value Enhancement Concentrator)

For years I refused to go near one.

It's all in the branding... What if the big Mac was sold as fried dead cow parts sold real cheap. Not the same market appeal as Two all beef patties ....

LOL

Sent from my LG-H872 using Tapatalk

 

[jimdoc]

fried dead cow parts, mixed with cardboard, sold real cheap

 

[Platdigger]

And hormones right? Don't forget the hormones.

 

[anachronism]

And hormones right? Don't forget the hormones.

Haha I spat my coffee all over my screen.

 

[cosmetal]

James

A cement mixer with varied steel balls in it works wonders. :lol: :lol:

Nick and I call ours the RVEC - sounds so much better than cement mixer.... (Rotary Value Enhancement Concentrator)

For years I refused to go near one.

Jon,

Catchy name . . . you and Nick should slap a trademark on it before Harbor Freight re-brands a line of their cement mixers. :lol: :lol:

Cheers,
James

 

[Tzoax]

"I just bought a USB microscope. I made a couple of random photos of gold bonding wires. It is little tricky to make a focus....but it is a huge difference comparing with my previous pictures made with magnifying glass..."

Welcome to the world of USB microscope photography!

Have you tried playing around with your camera's photograph resolution and image size?

Try using a higher resolution along with a smaller image size.

Good start though!

James

Thank you James, i made those pictures in 640x 480 resolution that is default. All other resolutions are not really better resolution but just zoomed in. I bought very cheap Chinese USB microscope - i payed it about 20$.
Anyway i am really satisfied with it - at least i can see gold bonding wires much clearer than before. If there is a need i will buy a better microscope.

On this test i used one gold bonding wire that i placed on CD ROM metal case, and i made pressure on it wirh screwdriver many times - and i used much of force.
Gold bonding wire:


So, after multiple pressures the majority of gold remained in a form of foils...


But at some places - a very tiny gold particles sticked on metal.

 

[FrugalRefiner]

I bought one much like yours, and I'm satisfied with it as well. I take my pictures at a high resolution and large image size, then use a free program called IrfanView to crop the image, readjust the image size, and save at a resolution that produces a good image with a small file size.

Dave

 

[Tzoax]

I bought one much like yours, and I'm satisfied with it as well. I take my pictures at a high resolution and large image size, then use a free program called IrfanView to crop the image, readjust the image size, and save at a resolution that produces a good image with a small file size.

Dave

Thats great, i am cropping and resizing images in "Paint" application that is included in any of version of Windows. One of the great tools is to sharpen image - for that when needed i am using any of free online photo editor websites.
Now i started to make my own application that is controlling USB microscope camera (that part i already finished - i can control microscope camera), so i will make automatic color recognition (that will include all shades of gold color) and the last part is to make tiny assembly line and a way to separate gold bonding wires (when detected).. I will try to make it and see how it works.

 

[Tzoax]

For better understanding - this is example how i am planning to detect gold bonding wires - by color. That will also include all of gold plated legs. Something like "optical separation". Legs would going on and as soon microscope camera detect gold color - legs/gold bonding wires would be redirected to separate container.

 

[FrugalRefiner]

Very cool!

Dave

 

[anachronism]

Colour sorting is a big thing in ewaste separation at a commercial level. There's some really interesting gear out there to do large volumes.

That given it works within tolerances so it's never perfect.

 

[patnor1011]

For better understanding - this is example how i am planning to detect gold bonding wires - by color. That will also include all of gold plated legs. Something like "optical separation". Legs would going on and as soon microscope camera detect gold color - legs/gold bonding wires would be redirected to separate container.

gif colors.gif

It is a cool idea to have fun but I can't see any real potential. I mean we talk about gold bonding wires which are so small you can't even see them properly. Also, IC does have hundreds of legs. How long do you think it will take to visually inspect material from just one IC? Multiply that then with hundreds of them required to process to make just 1 gram of gold.
Your camera will detect gold colour on nearly every leg as most of them are plated on the tip where bonding wire is usually attached.

 

[stella polaris]

Really nice photo's. I am grateful for you sharing all your great work!

Thank you rickzeien! I just made one test to see what would happen when gold bonding wire is detached from leg... I found this one for test:

1.jpg

The other side of leg:

2.jpg

Different light angles...:

3.jpg

4.jpg

5.jpg

Anyone that knows what material the silvershiny part on the legtip is made of? Is it a tin soldering or? If tin it could be an idea to seperate the gold in a temperature that holds the tin melted.

 

[Platdigger]

Gold and tin form an alloy. You will not separate with temperature.
Pure tin melts at 449.5F.
An alloy of 80% gold 20% tin melts at 532F.
This being a eutectic alloy, meaning the melting point is the same as the solid point.
Still trying to get my head around that one by the way.

 

[g_axelsson]

Eutectic just means that it will solidify all at once and not crystallize out another alloy at first. Eutectic alloys melts just like ice, it stop at a fixed temperature until all is either molten or solid.
An alloy that isn't eutectic will start to solidify one type of alloy rich in one component while the melt is getting richer in the other component, you get more and more solids while the temperature drops, until the liquid between the crystals reaches the temperature where it will solidify again... and the opposite when melting. In other words, there is a temperature span where there is both molten and solid metal.

That said, I strongly doubt that the ends on the lead frame is tin plated, it would form a physically weak bond, also have a huge risk of melting during soldering. My guess on the plating is gold on nickel, nickel or palladium.

Göran

 

[stella polaris]

Gold and tin form an alloy. You will not separate with temperature.
Pure tin melts at 449.5F.
An alloy of 80% gold 20% tin melts at 532F.
This being a eutectic alloy, meaning the melting point is the same as the solid point.
Still trying to get my head around that one by the way.

Well, the trick is to get the gold of the leg. For sure you are interested of a possible gold/tin alloy to come of as well. If it is tin heat might help get the gold ( and alloy) of the leg. Then you can take care of the tin/gold alloy separated from the leg. The silver shiny surface have been put on for some reason. If you can separate it from the leg the gold will follow. So the question remains. What is it the leg is tipped with?

Edit: The metal that its tipped with is that that holds the gold on to the leg. Since its a tiny amount of metal it must be possible to remove it. If Nickel as Göran suggest perhaps a Nickel electrolyte can take it of. If Palladium who would not like to collect it? Since a tiny amount even a crude electrolyte might do the job. The gold falls of and the palladium is collected.

 

[Tzoax]

For better understanding - this is example how i am planning to detect gold bonding wires - by color. That will also include all of gold plated legs. Something like "optical separation". Legs would going on and as soon microscope camera detect gold color - legs/gold bonding wires would be redirected to separate container.

gif colors.gif

It is a cool idea to have fun but I can't see any real potential. I mean we talk about gold bonding wires which are so small you can't even see them properly. Also, IC does have hundreds of legs. How long do you think it will take to visually inspect material from just one IC? Multiply that then with hundreds of them required to process to make just 1 gram of gold.
Your camera will detect gold colour on nearly every leg as most of them are plated on the tip where bonding wire is usually attached.

You got the point...with this cheap USB microscope it would definitely not be possible to make efficient color separation...and it is only because a very low refresh rate of cheap microscope cameras - sometimes it takes several seconds to show another picture frame, and sometimes it just freeze on one image...with investing in a more expensive camera (or many cameras) it is possible to make it efficient but i don't have such tendencies.

Currently i am testing silicon dies gold content for second time - but with different method.
First time i processed them directly to AR and the result was 0.71g/kg.

Now i used nitric acid to dissolve as much of silver i could, then i filtered the solution. And now it is ready for AR. I am making this experiment to see which way is better in a term of yields.

This is couple of pictures of silicon dies under microscope after nitric (nitric acid/distilled water - 50:50) treatment and filtering - a gold traces are beautiful.

 

[rickzeien]

Those are some great pics. Thanks

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[Tzoax]

I started with 196.1g of silicon dies. After processed with nitric acid i filtered the solution two times to capture all small particles and i processed those filters (charmin plugs) separatel.



This is another beaker with silicon dies.



AR solution...



Filtered AR solution



Dropped gold after mixing...



Particles are very small so i will wait until tomorrow to give a time for all of gold to settle down.