Electromagnetic and thermomechanic characterization and reliability evaluation

New possibilities for lifetime testing

Scanning Acoustic Microscope (SAM)-Transducer.
© Fraunhofer ENAS
Scanning Acoustic Microscope (SAM)-Transducer.

In order to address today‘s reliability challenges a few invest were necessary at the Micro Material Center department. Thanks to the massive invest of FMD (Research Fab Microelectronics Germany) in new production and characterization tools for the 13 partner institutes, we can now offer new very exciting lifetime evaluation methodologies to our customers. One of our latest development was centred on a self-made active power-cycling test set-up (2x8 samples, max. 500 A), which is now back-up with a brand new test-bench from Siemens / Mentor Graphics (12 samples, max. 1800 A) that features thermal transient measurement with structure function analysis. This two combine set-up allow for fast testing of larger batches of samples with combine application of temperature while actively powering the components. Thanks to those machines new more accurate lifetime models were already established for GaN power modules and presented in the PhD work of Dr. A. Otto. While testing component is the essence of building a lifetime model, investigating the failure mechanism is also of the highest importance. This is why, next to the already existing computer-tomography, cross-section and optical microscopy, we invested in a new Scanning Acoustic Microscope (SAM) which can accommodate samples from 200 µm up to 320 mm with an accuracy of 0,5 µm. The whole picture is completed with a state of the art shear tester to test material properties like adhesion or wire bond lift off.