Here is the abstract you requested from the IMAPS_2010 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Tape-Peel Testing as a Simple Method to Evaluate the Adhesion of Coated Layers on Metal Core PCB|
|Keywords: alternative Peel Testing, low cost process, adhesion testing|
|Conventional printed circuit boards (PCBs) may be replaced by thinner metal-core boards for some applications, as well as for package substrates. Using thin, metal-core technology may provide advantages for radio frequency (RF) circuits and packages, and increase heat dissipation for high power applications. The metal-core technology has several layers including the metal core, electro-coated dielectric, sputtered metal layers, and electroplated copper. For PCB and substrate reliability, it is important to have sufficient adhesion between the dielectric layer and plated copper. Sputtered metal layers with cleaning pre-treatments are a method to improve the adhesion. This paper describes an efficient testing method for the adhesion of a thin sputtered metal layer to a dielectric substrate. In this method, adhesive tape was attached to the surface and peeled off at 90 degrees in a tensile tester. Due to the sub-micron thickness of the sputtered layers, conventional peel test methods could not be applied. Typical adhesion testing of upper layers like paint coatings use a lattice pattern. The new method provided a convenient, repeatable way to evaluate the adhesion of three different sputtered metals with fifteen different pretreatment combinations. The test results were used to choose the sputtered metal and were later confirmed by testing the copper plated assembly using IPC-TM-650.|
|Bernd Scholz, Research Engineer
North Dakota State University; Center for Nanoscale Science and Engineering; Center for Nanoscale Science and Engineering