The proliferation of counterfeit electronic components has necessitated the need for more sophisticated detection techniques. X-ray examination is a non-destructive test used to verify the internal contents of a semiconductor package including the presence of a die, the integrity of the wire bonds, lead frame condition, and the consistency of the internal elements of each device of the lot under test. USBid's new subsidiary, Electronic Component Analytics Lab (ECAL) is equipped with an 80kV, 5um resolution x-ray system.
The following is a photo of a AS7C409615JCTR SRAM device from Alliance Semiconductor taken with the system.
The die, chip and lead frame were consistent on all products tested and the product came from Alliance via a franchised distributor, therefore the part will be classified as a Known Good Device (KGD) for future analysis purposes.
|Figure 1.) 80kV X-Ray System in Action|
|Figure 2.) X-Ray of Known Good Die (KGD)|
Another recent order for 800 pieces of a National Semiconductor CD4071BCN, produced much different results. Date codes for most of the devices were from the early 90s and the first 50 pieces produced three different lead frames, different die sizes and some with no die at all.
|Figure 3.) Lead Frame & Die Size #1|
|Figure 4.) Lead Frame & Die Size #2|
|Figure 5.) Lead Frame #3 - No Die|
X-ray inspections can also be used to measure the die dimensions for comparison to manufacturer’s published data. The inspections can be performed without removing the parts from their ESD bags or Moisture Barrier Bags (MBB) – place the bag directly in the chamber without breaking any seals.
X-ray systems do have limitations – they can’t magnify an image enough to observe information of the die such as logos, part numbers, company names, etc. In addition, the x-ray beam’s ability to detect images of die mounted in ceramic packages requires a higher voltage x-ray tube to attain resolution comparable to plastic epoxy devices.
In order for X-ray examinations to conclusively determine the authenticity of the device being inspected, an X-ray photograph of a KGD is required. However, a thorough evaluation of the entire lot that reveals consistent conformity to die, bond wires and lead frames throughout the lot reduces the probability of sub-standard or counterfeit product substantially.
USBid Inc. is an independent distributor of electronic components located in Palm Bay, Florida, USA. Since 1998, we have been helping customers locate and purchase hard-to-find and long lead time components. We are AS9120 and ISO 9001:2008 certified and ESD S20.20-2007 compliant. USBid.com understands that sourcing parts in the “open market” is challenging. That’s why we conduct visual, physical, and chemical analysis of all orders and offer electrical parametric testing to manufacturer datasheet specifications. For more information, checkout our USBid Inc.Overview on YouTube.