Dear expert community,
I do replacements of BGA chips, mostly on laptop motherboards.
When motherboards come from factory, they usually have a red substance (I believe it is epoxy) on the corners of BGA chips, to help battle mechanical stress to the components,
like the one on the picture below.
In the process of reworking BGA chips I need to heat the red epoxy to around 150 Celsius and remove it with a wooden toothpick or similar object.
When I attach a new BGA chip, I like to use similar epoxy around the edges / corners of the chip, but I am having trouble finding the substance with the similar properties to the one from the factory:
- It needs to be red in color, even after curing
- It needs to be re-workable; If BGA chip needs to be removed again, the epoxy should come of with the help of heat (around 150 Celsius) and wooden toothpick
- The shelf life for an open product should be at least 6 months.
I have tried a few SMD adhesives / glues from eBay, but none is perfect, some are not re-workable (they cannot be removed even after heating it to 250Celsius) and others change color to black when heat cured.
The latest product I have tried is PR2035E/5R PERMACOL, but it changes color from red to black when heat cured at 100 Celsius for 6 minutes.
I am now looking at ELECTROLUBE SMA10SLSMA10SL ADHESIVE from Farnell, does anyone have any experience with this product, does it turn to black when heat cured or does it stay red and is reworkable - can be removed after being cured?
Thank you for your help,
Simon
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