Overview of Our PCB Failure Analysis Services
The modern printed circuit board (PCB) is comprised of hundreds of individual components, multiple layers of copper conductors and fire retardant insulators, and countless vias, plated through holes, and connectors.
Despite the microelectronics industry’s best efforts, 100% yield and perpetual reliability from PCB manufacturing have yet to be realized; manufacturing defects, early life failures, and improper use are still inescapable facts of life.
PCB failure analysis aims to identify and study these defects and damaged devices so that microelectronics manufacturing processes can be improved and the lifespan of PCB products can be extended.
Fundamentals of PCB Failure Analysis
Just as with our integrated circuit (IC) failure analysis services process, PCB failure analysis can be broken down into four main phases. After a failing PCB has been received, it is first non-destructively tested, going through an in-depth optical and x-ray inspection of the electronic component to document any immediately obvious anomalies that might have caused the failure.
Next, the analyst verifies the fault on the printed circuit board, recreating the circumstances under which the device was reported to fail to confirm that the system is still malfunctioning.
With a confirmed failure, the next step is fault isolation - an analyst might use thermal imaging or time domain reflectometry to identify a potential problem on the PCB, or may simply use hand probes to trace signals along a board looking for anomalous connections. The goal of fault isolation is to identify a target for destructive analysis and documentation; an analyst might use methodical probing to isolate an open circuit to a single via, for example, which can then be cross-sectioned to reveal improper etchback or mechanical stresses.
An analyst checks the outputs of a PCA on the oscilloscope
Oftentimes, the old methods are the best - hand-probing points on a PCB like this is a quick way to take electrical measurements
A delayered BGA substrate, showing scorch marks indicating a high current short circuit
Cross-section micrograph of a plated thru hole, showing an open circuit
A do-it-yourself crystal growth experiment gone horribly wrong! Contamination on this PCB ran wild, eventually causing the device to fail.
This lotus bloom is actually a cluster of crystals growing on a PCB - bad news for reliability!
Whether your failing product is a freshly produced PCB or a fully populated printed circuit assembly (PCA / PCBA), IAL has the capabilities to chase down even the most subtle of failures.
With our wide range of capabilities, we can isolate and document defects in the PCB itself, in the components on the board, or even environmental factors that caused the failure (e.g. contamination).
- Examining solder or plating failures
- Characterizing the effects of mechanical stresses on a PCB product
- Identifying the root cause of PCB conflagration
- Inspecting PCBs after initial qualification and reliability testing
Since the modern circuit board is so complex, an analyst will often not be able to completely trace a signal based on visual cues alone; buried traces and blind vias obscure the signal path from the naked eye. Should you have access to Gerber files or other drawings showing the layout of the board, providing them can greatly simplify the failure analysis process.