Gamma radiations effects on MEMS RF type switches with Al2O3 dielectrics thin layers

Here are presented preliminary investigations on the effects of the gamma radiation total dose on the running of capacitive switches Memos RF carried out with aluminium oxide dielectric layers. MEMS components prepared with different types of aluminium oxide (obtained by plasma assisted chemical vapor deposition PECVD or by laser ablation) and different thicknesses (200 or 400 nm) have been tested. The experiments carried out using a Co60 gamma radiation source clearly show the appearance of the dielectrics load effects, modifying the running of the MEMS. The effects increase with the total dose but the greater part of the components remain functional even after high total doses (88 krad). These results, correlated with hyper-frequencies measurements of the irradiated MEMS suggest that in the test conditions and for this particular type of components, the gamma radiation has weak to moderated effects. (O.M.)