Failure Analysis of Integrated Circuits

The semiconductor industry continues to shrink the size of electronic devices; the current state-of-art commercial technology nodes for integrated circuits are 14 and 22 nm, however, yet to come are 10 and 7 nm technology nodes which are still in the developmental stage.
Such integrated circuits are multilayer structures whose key elements are multi-gate transistors, where a source-drain channel („fin“) is surrounded by a 3D gate.
  • A failure analysis process of such integrated circuits typically involves delayering and electrical nanoprobing. After the defective area is found a lamella containing the failure of interest can be prepared for TEM inspection.
  • So far, delayering has been performed mainly by means of mechanical polishing. However, for future devices mechanical polishing cannot be used due to micro and nano mechanical deformation and chemical interactions with polishing suspension.
  • TEM lamella preparation is done on FIB-SEM systems. These lamellae must be artefact-free with the thickness proportional to the technology node.

Failure analysis of integrated circuits typically includes:

  • Delayering and electrical probing in technology nodes of last generation
  • Preparation of TEM lamella from integrated circuits
  • FIB-SEM tomography for 3D structural analysis (3D BSE reconstructions) 
  • Electrical fault isolation (EBIC, EBAC)
  • Low voltage SEM inspection
Failure Analysis of Integrated Circuits
14 nm technology node Intel processor. A top view of the transistor contact layer after delayering by GIS-assisted Xe Plasma FIB etching, image obtained at an electron accelerating voltage of 500 V with the In-Beam detector

Related Application Notes

FIB Tomography of an Integrated Circuit
FIB tomography has become an important tool for studying materials at the micro and nano scale. Unlike a single cross-section, FIB tomography gives better understanding of the volume distribution, 3D structure and the relationship between three dimensional objects. TESCAN FIB-SEMs can be equipped with 3D Tomography - an optional software module for automated data acquisition and reconstruction.
pdf – 1.4 MB
Two isosurfaces with different threshold extracted from the volume data
Two isosurfaces with different threshold extracted from the volume data