Ceramic capacitors are used typically very small, inexpensive devices which are used in cell phones, MP3 playter, computer and other electronic products. MLC devices are constructed of alternating layers of metal and ceramic, with the ceramic material acting as the dielectric.
Microstructural analysis of BaTiO3 ceramic capacitor includes looking for void and missing metal layers, as well as for gaps and voids in the ceramic substrate. Microstructural preparation of mulit-layer BaTiO3 ceramic capacitors requires minimizing polishing relief between the metal layers, coating or substrate voids, and the ceramic substrate. This is accomplished by filling the apparent voids during mounting by pouring the castable resin under vacuum and then curing under pressure. Initial grinding with alumina lapping films is required to open up the capacitor, as well as to minimize microstructure damage. Rough and final polishing are recommended on low nap polishing pads using diamond and colloidal silica, respectively.
SECTIONING
Not required
MOUNTING
Castable mounting acrylics or epoxies
POLISHING
Abrasive/surface |
Lubricant |
Force/ sample |
Time |
45 micron alumina lapping film |
Water |
5 lbs |
Until plane |
15 um DIAMAT diamond on POLYPAD polishing pad |
DIALUBE Purple Extender |
5 lbs |
3 minutes |
6 um DIAMAT diamond on GOLDPAD polishing pad |
DIALUBE Purple Extender |
5 lbs |
3 minutes |
1 um DIAMAT diamond on ATLANTIS polishing pad |
SIAMAT colloidal silica |
5 lbs |
2 minutes |
 |
BaTiO3 Multi-layer Ceramic Capacitor |
 |
BaTiO3 Multi-layer Ceramic Capacitor with void in metal layer |