Investigation of silicon nitride charging

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

“…The existence of such ''fixed'' charges has been also reported in MISS devices with an a-SiN x :H gate quality insulator deposited with PECVD method at 260°C [35], where the shift of C-V characteristics after positive stress revealed a thermally activated mechanism with s = 3.6 Â 10 s. This mechanism has been attributed not to the creation of dangling bond defect states in a-Si:H but to trap states in the a-SiN x :H insulator [35]. The activation energies of the discharging process obtained in this work is in excellent agreement with our previously reported results [9,19] as far as it concerns thermally activated charging mechanisms in SiN x . The fact that charging and discharging processes in MEMS switches are thermally activated means that the parameters affecting the device lifetime are thermally activated too.…”

“…This activation energy practically coincides with the one obtained from TSDC method in MIM capacitors [9], where above room temperature the TSDC current can be described by:…”

“…So far, the discharging process has been investigated in MetalInsulator-Metal (MIM) capacitors with the aid of thermally stimulated depolarization currents (TSDC) method [8][9][10], by recording the charging and discharging current transients (CCT and DCT) [11] and recently with the aid of Kelvin probe force microscopy (KPFM) method [12,13]. In capacitive MEMS switches the discharging process differs from the one in MIM capacitors, since in MEMS the injected charges are collected only through the bottom electrode when the suspended electrode is in the pull-up state.…”

Induced charging phenomena on SiNx dielectric films used in RF MEMS capacitive switches

“…5b). Up to now charging asymmetry has been observed for the case of contacted charging in MIM capacitors and MEMS switches [23][24][25]. The above mentioned results demonstrate for first time that the induced charging in HF PECVD SiN x films is also an asymmetric process.…”

A study of field emission process in electrostatically actuated MEMS switches

“…The build up of parasitic charge is responsible for undesirable switch behavior and limits its lifetime [3][4][5]. Therefore this phenomenon has been studied intensively by several authors employing a variety of techniques [6][7][8][9][10][11][12][13].…”