Failure of microelectronic devices is often due to the failure of an interconnection bond. A common type of interconnection bond is the thermo compression or thermosonic gold wire bond. A very important element of this interconnection is the first bond or ball bond. These test methods can assist in maintaining control of the process for making ball bonds. They can be used to distinguish between weak and nonadherent ball bonds, of both, and bonds that are acceptably strong.

These test methods are appropriate for on-line use in process control, for process development, for purchase specifications, and for research in support of improved yield and reliability. Since the ball shearing method tests only the first bond in a microelectronic wire bond interconnection system, it must be used in a complementary fashion^{6 ,7} with the wire bond pull test.³

1.1 These test methods cover tests to determine the shear strength of a series of ball bonds made by either thermal compression or thermosonic techniques. Note 1Common usage at the present time considers the term "ball bond'' to include the enlarged spheriodal or nailhead portion of the wire, (produced by the flameoff and first bonding operation in the thermal compression and thermosonic process, or both,) the underlying bonding pad, and the ball bond-bonding pad interfacial-attachment area or weld interface.

1.2 These test methods cover ball bonds made with small diameter (from 18 to 76-µm (0.0007 to 0.003-in.)) wire of the type used in integrated circuits and hybrid microelectronic assemblies.

1.3 These test methods can be used only when the ball height and diameter are large enough and adjacent interfering structures are far enough away to allow suitable placement and clearance (above the bonding pad and between adjacent bonds) of the shear test ram.

1.4 These test methods are destructive. They are appropriate for use in process development or, with a proper sampling plan, for process control or quality assurance.

1.5 A nondestructive procedure is possible; although it may be contra indicated due to the possible interference with adjacent wire bonds and microcircuit components.

1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.