1 Scope

This part of IEC 60749 establishes a means for determining the strength of a ball bond to a die or package bonding surface and can be performed on pre-encapsulation or post-encapsulation devices. This measure of bond strength is extremely important in determining two features:

1. the integrity of the metallurgical bond which has been formed, and

2. the quality of ball bonds to die or package bonding surfaces.

This test method covers thermosonic (ball) bonds made with small diameter wire from 15 µm to 76 µm (0,000 6" to 0,003").

This test method can only be used when the bonds are large enough to allow for proper contact with the shear test chisel and when there are no adjacent interfering structures that would hinder the movement of the chisel. For consistent shear results the ball height will be at least 4,0 µm (0,000 6 ") for ball bonds, which is the current state of the art for bond shear test equipment at the time of this revision.

This test method can also be used on ball bonds that have had their wire removed and on to which a second bond wire (typically a stitch bond) is placed. This is known as "stitch on ball" and "reverse bonding". See Annex A for additional information.

The wire bond shear test is destructive. It is appropriate for use in process development, process control, or quality assurance, or both.

This test method can be used on ultrasonic (wedge) bonds, however its use has not been shown to be a consistent indicator of bond integrity. See Annex B for information on performing shear testing on wedge bonds.

This test method does not include bond strength testing using wire bond pull testing. Wire bond pull testing is described in IEC 60749‑22‑1.