Cell Phone Chip Cover Removal

[ddrecovery]

Any advice on the best way to remove the silver metal chip covers from this cell phone board.
I have a hot air station, solder station and I/R SMD/BGA rework station.

Attachments

[jeremyb]

Carefully

Hot air would be my preference assuming you have a decent station

[rogfanther]

Also, depending of what there is on the other side of the board, and if the board needs or not to be restored to function later, you can use a hot plate ( sorry, forgot the right name, like a clothes iron business side up ) on the underside to help warming the board.

[ddrecovery]

Thanks guys. I did get the covers off and got to the eMMC chip. Unusually (at least I think so), this eMMC chip was not encrypted, XOR'd or anything else. Got the folder structure just by reading it. Looks like the phone just used if for storage. Thanks again.

[arvika]

Of course it use XOR or anything else. eMMC chip has inside controller and memory chip. If controller works, you can access data similar like for SD card or pendrive.

[ddrecovery]

Of course it use XOR or anything else. eMMC chip has inside controller and memory chip. If controller works, you can access data similar like for SD card or pendrive.

Sorry, what I meant to say was that we didn't need to apply XOR or any other conversion.

[data-medics]

What are you using for an eMMC reader? I really try to stay away from the phone recoveries, but have been considering buying at least an eMMC reader. I know they are now even using eMMC in cheap-o laptops at Best Buy, so probably will be seeing a lot more of them soon.

[ddrecovery]

What are you using for an eMMC reader? I really try to stay away from the phone recoveries, but have been considering buying at least an eMMC reader. I know they are now even using eMMC in cheap-o laptops at Best Buy, so probably will be seeing a lot more of them soon.

I have a set of the new Rusolut eMMC adapters. They plug into any commercially available eMMC reader.

[arvika]

Rusolut adapters looks like on photos below. Very good tool, every eMMC chip has own adapter - they have different sizes, fits very well to socket. No problem with positioning, no risk that you connect VCC to GND pad etc. You connect adapter like SD card.

Attachments

[jeremyb]

Any advice on the best way to remove the silver metal chip covers from this cell phone board.
I have a hot air station, solder station and I/R SMD/BGA rework station.

Use Chip Quik SMD Removal Alloy. It lowers the melting point of the solder.

[LarrySabo]

Any advice on the best way to remove the silver metal chip covers from this cell phone board.
I have a hot air station, solder station and I/R SMD/BGA rework station.

Use Chip Quik SMD Removal Alloy. It lowers the melting point of the solder.

ChipQuik requires that the lead-free solder reach liquidus (217C) so the Bismuth can blend to form the allow with its lower melting temperature, so I don't see how that would work here. I would expect a hot air or IR BGA rework station would be required but have no personal experience with this device.

[jeremyb]

Any advice on the best way to remove the silver metal chip covers from this cell phone board.
I have a hot air station, solder station and I/R SMD/BGA rework station.

Use Chip Quik SMD Removal Alloy. It lowers the melting point of the solder.

ChipQuik requires that the lead-free solder reach liquidus (217C) so the Bismuth can blend to form the allow with its lower melting temperature, so I don't see how that would work here. I would expect a hot air or IR BGA rework station would be required but have no personal experience with this device.

According to the manufactures site:
Chip Quik Alloy Melting Point: 58 Celsius (136 F)

That's practically nothing. Use your iron to add some of this stuff in with the lead-free solder, just be careful because if this stuff gets on any passives they'll float off the PCB while you're using hot air.

[LarrySabo]

According to the manufactures site:
Chip Quik Alloy Melting Point: 58 Celsius (136 F)

That's the melting point of the alloy, but to become an alloy, the bismuth needs to mix with the lead-free solder, which means it has to reach 217c. I can't see how/where the metal covers are bonded to the board/chips and assumed the solder joints are hidden beneath the metal. If they are at the edges, then sure, give ChipQuik a try.

As for hot air versus IR, I think hot air would be his best bet, since the IR will not likely be absorbed well by the metal covers.

[jeremyb]

According to the manufactures site:
Chip Quik Alloy Melting Point: 58 Celsius (136 F)

That's the melting point of the alloy, but to become an alloy, the bismuth needs to mix with the lead-free solder, which means it has to reach 217c. I can't see how/where the metal covers are bonded to the board/chips and assumed the solder joints are hidden beneath the metal. If they are at the edges, then sure, give ChipQuik a try.

As for hot air versus IR, I think hot air would be his best bet, since the IR will not likely be absorbed well by the metal covers.

You're argument is that since you've never tried it then there is no chance of success?
If you look at the picture you'll see the tabs bonding the covers to the PCB are on the outside..

[LarrySabo]

You're argument is that since you've never tried it then there is no chance of success?
If you look at the picture you'll see the tabs bonding the covers to the PCB are on the outside..

My argument was based on my ignorance of where the covers were attached to the PCB. If the OP can get a soldering iron into the joints, ChipQuik should help a lot. If not, a hot air rework tool should do the trick.

Mainly, I was trying to point out that ChipQuik still requires the solder to reach 217C in order to blend with the bismuth to form the alloy.

[ddrecovery]

Sorry for my slow respose, I have been training in Poland for the last week.

I did use a mixture of Chip Quick and brute force. The phone was water damaged beyond repair so chip removal was the only option. As I didn't need to save the board, I used CQ on one side of each cover and kept heating until it came loose, I could then lift the cover off from the one side and peel it back from the board. Not recommended if you need to save the board, but this doesn't affect the chips.

I did try hot air, but the heat disipation was too great and could never get all the cover heated at once, or at least I was concerned about the chip temp inside the cover. That's when I went for CQ. IR may work, will try that next time.

[jeremyb]

Deleted by me

Last edited by jeremyb on July 24th, 2016, 20:37, edited 1 time in total.

[jeremyb]

Mainly, I was trying to point out that ChipQuik still requires the solder to reach 217C in order to blend with the bismuth to form the alloy.

I'm not sure, It seems like it amplifies the heat if that makes any sense like insulation.. Cool stuff

Sorry for my slow respose, I have been training in Poland for the last week.

Learn any good tricks?

[Robert_Kidd]

Any advice on the best way to remove the silver metal chip covers from this cell phone board.
I have a hot air station, solder station and I/R SMD/BGA rework station.

Use Chip Quik SMD Removal Alloy. It lowers the melting point of the solder.

Does it really work?

[ddrecovery]

Learn any good tricks?

Yes, but not of any interest to NAND bods, it was a RAID recovery class with D3 Consulting. VNR is next