Voltage and temperature effect on dielectric charging for RF-MEMS capacitive switches reliability investigation

In this paper, we study the effect of stress voltage and temperature on the dielectric charging and discharging processes of silicon nitride thin films used in RF-MEMS capacitive switches. The investigation has been performed on PECVD-SiNx dielectric materials deposited under different deposition conditions. The leakage current was found to obey the Poole–Frenkel law. The charging current decay was found to be affected by the presence of defects which are generated by electron injection at high electric fields. At high temperatures power law decay was monitored. Finally, the temperature dependence of leakage current revealed the presence of thermally activated mechanisms with similar activation energies in all materials.