Students presents results graduation project
Presentation Day at CITC for our student Subba Kedarnath Gupta Vemula. After six months of hard work, he shared the results with our team. Subba’s research consisted of a performance evaluation of pressureless copper sinter paste for power electronics applications.
Alternative for silver paste
Copper could be an attractive alternative to silver paste, but there are still many parameters that need to be refined. Therefore, Subba conducted both a coupon-level evaluation and a packaging evaluation.
For the copper coupon, he developed a process workflow, and after selecting the best process, he built PQFN samples on lead frames. He subjected these to various qualification tests, such as void analysis and die shear testing.
Next, the samples were assembled on test boards, electrically tested and put on lifetime testing. This involved much hands-on work and many hours in CITC’s assembly and testing labs.
Open questions
The conclusion after all this work is that there are still many open questions regarding this process. However, the results also provide reason to believe that an alternative material to silver paste will enter the market in the long term.
After Subba’s presentation, he received quite a few questions from the team; he is therefore now optimally prepared for the defense of his master thesis at Technische Universität Darmstadt. Team CITC, particularly his supervisors Frans Meeuwsen, Edsger Smits and Henry Antony Martin, is confident in a successful outcome.