Various Methods for Die Attach
For the die attach process we usualy use thermoplastic films from Cookson - Staystik.
Thermoplasts are polymer materials consisting of linear chains without
cross-links.
Therefore they can be heated above the so-called glass transition point
where they become flowable again and rework can be done. They harden again
when cooled down.
Staystik films exist with or without filler
materials. One can therefore choose between a range of materials from high
thermal and electric conductivity to thermally and electrically insulating.
The standard materials used in the Bondlab are:
the electrically and thermally conductive
Staystik film type 571
and
the
thermally conductive
Staystik film type
672
There is an important
constraint: the interface to be bonded needs to be heated to about 170°C
under gentle pressure for about 10 secs. For this purpose, a Cammax Die
Bonder set-up is used.
The thermoplastic Staystik film 571 has been
verified from
radiation hardness
point of view, in the
CERN PS irradiation facility.
Epoxy
glues
For all work requests which require the use of an
alternative adhesive to the Staystik films, we would kindly ask the user to
provide the adhesive, the MDS documentation and the data sheet.
Anisotropic glues
Some preliminary studies have been performed with anisotropic glues as an alternative to wire bonding in
certain applications.
(Report)
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