Printed Circuit Board Electronic Failure Analysis

Whether measuring plating thickness, cross sectioning vias, identifying foreign materials or finding defects in the board, IAL has the expertise and equipment to isolate the cause of failure.

Today’s Printed Circuit Boards (PCBs) have evolved from 100% through-hole, 100-mil technology to a mixture of through-hole and surface mount processes involving thousands of components and precision to 1-mil tolerances (5-mil spacings).

Double-sided boards have evolved into multi-layer boards where 5 and 6 layers are now very common as many as 14 layers have been used.

 As the complexity of the PCB manufacturing process has increased, the possibility of process defects has also increased. A PCB has many potential causes of failure:

  • Metal traces not to specification
  • Broken buried metal lines
  • Vias
  • Delaminations of the board
  • Component misalignment
  • Bad components
  • Cold-solder joints

These are traditional types of PCB defects that must be addressed on a daily basis. To complicate the situation further, it is now very common to have Chip-on-Board (COB), the direct mounting and wiring of an integrated circuit on the PCB. Flip chips and Ball Grid Array packages may be on the PCB as well.

These technologies, while providing a very dense board layout, also pose new challenges to the board manufacturer: tighter tolerances, more fragile die, underfill, and solder contacts that are not visible to the naked eye.

To address these concerns, IAL has assembled equipment to identify the specific problem and the root cause. This equipment and its capabilities are:

 

Radiography (X-ray imaging)

Highlights cracks and other physical defects in the vias, buried metals, wires and other materials. Good for examination of hidden solder joints (such as BGAs, flip chips, etc.)

Acoustic Microscopy

Reveals cracks, delaminations, and voids in plastics and other materials. Complements radiography. Can image underfill voids and hidden solder joints.

X-ray Fluorescence

Measures the thickness and composition of films such as solder, copper, nickel, gold etc. used in the manufacturing of PC-boards. Helps maintain process control.

Surface Analysis

From contaminants on the board to dust found in the system, surface analysis techniques can be useful in identifying the source of the problem.