Murata has announced a water-repellent monolithic ceramic capacitor developed by applying an innovative surface treatment.
The miniaturisation of electronic devices, densely packed with components can cause an increase in the possibility of malfunctions influencing circuit operation due to ion migration.
Ion migration may occur when voltage is applied to a capacitor where moisture is present between the electrodes. This may result in the anode metal becoming ionised and changing to a cathode. Then, when gaining electrons as a cathode, the metal may undergo the electrochemical phenomenon of deposition and growth that can eventually result in a short-circuit.
To address this issue Murata has developed a water repellent monolithic ceramic capacitor which is treated with a water-repellent treatment film so that moisture forms into scattered, rather than larger, droplets. These droplets are suppressed to a size that is not big enough to span the gap between the external electrodes, preventing ion migration.
This capacitor has applications particularly in navigation systems, body control electronic control units (ECUs), air conditioner ECUs, meter ECUs and engine ECUs.