Focused ion beam (FIB) analysis uses a finely focused ion beam to mill, image, and modify integrated circuits with nanometer-scale precision. In failure analysis, FIB produces site-specific cross-sections through defects localized by fault isolation, and FIB circuit edit cuts and reconnects circuit traces to validate design fixes without a new silicon spin.
FIB analysis is also referred to as FIB cross-sectioning, FIB milling, and FIB circuit edit (FIB-CE).
FIB Capabilities
- Site-specific cross-sections: precise cuts through a defect located by PEM, XIVA™, or other fault isolation techniques, revealing its physical cause.
- Ion beam imaging: channeling contrast that reveals metal grain structure and voids.
- Circuit edit: cutting traces and depositing new conductive connections to rewire a circuit for design debug and validation.
- Probe point creation: exposing and building pads on internal nodes for electrical probing.
How FIB Works
A focused beam of ions is scanned across the sample, sputtering away material in a precisely controlled pattern. Combined with gas-assisted deposition, the same system can add conductive or insulating material at specific locations. Because material is removed only where the beam is directed, FIB can expose a single defect or reroute a single trace without disturbing the surrounding circuitry.
FIB in the Failure Analysis Workflow
- Fault isolation localizes the failure site on the die.
- FIB mills a cross-section precisely through that site.
- SEM imaging and EDX analysis characterize the defect and identify the root cause.
Backside Circuit Edit
On dense, multi-metal-layer devices and flip-chip packages, frontside access to target nodes is often blocked by metal routing. Area defined die thinning removes substrate from a selected region so that circuit edits can be performed through the backside of the die, bypassing the obstructing metal layers.
Turnaround and Deliverables
Typical turnaround for FIB cross-sections is 2 to 3 days. Circuit edit timelines depend on the number and complexity of edits and are quoted per project. Results are documented with annotated images in an engineering report.
Related Services
- Scanning Electron Microscopy (SEM/EDX)
- Semiconductor Fault Isolation
- Area Defined Die Thinning
- IC Delayering and Deprocessing
- Cross-Sectioning Services
Frequently Asked Questions
When is a FIB cross-section used instead of a mechanical cross-section?
FIB is used when the target is a single transistor, via, or defect too small to reach reliably by mechanical polishing. Mechanical cross-sectioning is better suited to larger structures such as packages, solder joints, and circuit boards.
What is FIB circuit edit?
FIB circuit edit modifies an integrated circuit by cutting existing traces and depositing new connections. It lets design teams test a fix on real silicon before committing to a new mask set.
Can circuit edits be performed from the backside?
Yes. After area defined die thinning, circuit edits can be performed through the substrate, which is often the only practical route on dense or flip-chip devices.
Request FIB Analysis
Watson Analytical is an ISO 9001:2015 certified, ITAR-registered failure analysis laboratory in San Diego, California, serving semiconductor, defense, space, biomedical, and litigation customers. Contact us to discuss your device and request a quote.