Remarking Tests, RTS Screening and permanency
This testing process will be able to confirm and determine if the device has been remarked or resurfaced. As a part of counterfeiting many suppliers used an older date code or slow speed devices, and refurbished them to appear new and marked as higher grade or with a recent date code or as RoHS compliant. Counterfeiters have access to reclaimed, scrapped and excess parts, which are easily available from unauthorized sources. These tests consider a destructive test. Re-Surfacing / Re-Marking test are based on AS5553, MIL-STD-202 and JESD22-B107C.
Heated Chemical Testing
Heated Chemical Testing or HCT is performed on an electronic component or IC device to check for a secondary coating. This process is performed by heating a specific chemical to a certain temperature. Once temperature is reached, a plastic IC device is submerged half way into the chemical. When left over a specific period of time the partially cured resins, paint, blacktop, or secondary coating will be dissolved. After this process is complete a clear picture is taken under a microscope to show a secondary coating if the device had one.
A secondary coating is not the only thing the HCT reveals during this process. Because the coating is removed during this process on a refurbished device, other things can be seen like:
• Exposed sanding marks from sanding process
• Bead blasting marks on the surface of the device
• Previous device markings
• Pin indicator
• Remark devices to all one date code
• Change speed grade rating from C (Commercial) grade to I (Industrial)
• Covering pull marks, chips, cracks, or other inconsistencies
• Exposed bond wires
This step is very effective in determining if a secondary coating has been applied. Blacktopping is a common process used by counterfeiters.