Temperature effects on the bulk discharge current of dielectric films of MEMS capacitive switches

Abstract

Kelvin probe method has been directly applied to capacitive MEMS switches in order to investigate temperature activated mechanisms in PECVD Silicon Nitride (SiNx) films. The bulk discharge current of MEMS capacitive switches has been determined for different charging and discharging temperatures, in the range of 300–400 K. The increase of discharging temperature leads to an increase of the magnitude of the bulk discharge current and the relaxation time of the discharging process is found to be thermally activated. Finally, it is shown that the increase of charging temperature assists trapping at centers characterized by time constants even longer than the time window of observation, i.e. 10^4 s.