Wedge finish is determined
by user preference. All Gaiser wedges come with standard EDM matte finish on the bond foot
of the wedge. The standard EDM matte finish is commonly used for both
and gold wire. In some cases, a fine matte
finish is preferred for aluminum wire to minimize the build-up of aluminum
on the bond face of the wedge.
This wedge, p/n2131-2525-3/4-FMF, is used for
aluminum wire. The fine matte finish (FMF) is recommended when the bond foot is building
up with aluminum wire too quickly.
In some cases the entire bond foot is polished
in an attempt to minimize build-up on the bond foot of the wedge. As the
polishing of the bond foot inhibits good transference of ultrasonics, the
foot (PBF) is not recommended unless other options fail to provide the desired
results. The PBF may also be called out if a requirement for having shiny
bonds instead of matte finish bonds is required.
This wedge, p/n2131-2525-L-PBF, is used when there is
an extreme build-up problem or a shiny bond appearance is required.
For gold wire applications,
the cross groove (CG) modification and/or a rough matte finish may be required to enhance
the transfer of thermosonic energy between the wire and the wedge.
The rough matte finish (RMF) can be used when the BL is too short for a CG. The RMF can be called out on all
materials but works best on the Au (Gold) and the BKCER materials.