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Fraunhofer Institute for Silicon technology ISIT
Service Offers
Apart from the research work done in
semiconductor and micro systems tech-
nology, ISIT offers many processing, qual-
ification, and test steps as a service for
our industrial customers. Many years of
experience with electronic assemblies en-
ables the engineers to elaborate solutions
in packaging processes, in manufactur-
ing quality evaluation, in reliability and
lifetime testing, as well as in failure and
damage analysis. Within research pro-
jects, the design and production of appli-
cation specific power devices (MOSFETs,
IGBTs) has been accomplished.
Further Institute Highlights are:
•
Semiconductor production line in co-
operation with Vishay Siliconix Itzehoe
GmbH
•
IC Technology
•
Micro systems - MEMS
•
EN ISO 9001:2008 certified quality
management system
Packaging Technology
Conventional and advanced packaging
technologies are available, e.g. paste
printing, component or die placement,
and reflow soldering (vapour phase, vac-
uum). Soldering process development
can be done by in-situ x-ray observation
of the melting process even with vacuum
applied. Semiconductor chip top connec-
tions are made by large wire bonding,
but new assembly concepts are evalu-
ated with wafer level chip size packages
(WLCSP) or with modified metallisations,
e.g. by wafer level NiAu plating on the
standard Al metallisation.
Quality and Reliability
Static and dynamic electrical measure-
ments confirm data sheet values,
e.g. break through voltage, on resistance,
stationary and transient thermal resist-
ances. Several power cycling test benches
(current up to 2 kA) are available for reli-
ability testing.
A dedicated power supply allows testing
of photo voltaic inverters (solar panel and
field simulation) and IR thermography
(Lock-In) is used to reveal hot spots.
Analysis is done by x-ray inspection, scan-
ning acoustic microscopy, scanning elec-
tron microscopy, as well as by metallo-
graphic cross sections.
Modelling
Modelling of thermal performance (ther-
mal resistance, stationary and transient)
has been applied to assemblies and cool-
ing units (air, water). Modelling of the
thermo-mechanical behaviour of assem-
blies and the damage mechanisms evalu-
ates critical loads and allows the predic-
tion of lifetime due to creep and fatigue.
Metallographic cross section of a power module assembly
Lead frame power module with ISIT MOSFETs
(NELE), ready to be epoxy moulded
Power module reliability, experiment and model
prediction
