What is decapsulation in failure analysis?

Decapsulation, or decap, is a failure analysis technique that involves removing the outermost layers of a microelectronic device to examine the internal structures and identify the cause of a failure. This technique is commonly used in the semiconductor industry to identify defects or malfunctions in integrated circuits or other microelectronic components.

During decapsulation, the device is typically placed in a chemical solution or etchant that dissolves or removes the outer packaging material, such as a plastic or ceramic encapsulant, exposing the underlying components. The process can be done using mechanical, chemical or laser techniques.

Once the encapsulant has been removed, the internal structures of the device, such as the bond wires, die, and other components can be analyzed. By examining the internal structures, failure analysts can identify issues such as cracks in the die, bond wire failures, or other types of defects that may have caused the device to fail.

Overall, decapsulation is an important technique in the field of failure analysis, as it allows engineers to gain a deeper understanding of the root cause of a failure and develop solutions to prevent similar issues in the future.