Wafer-level micropackaging in thin film technology for RF MEMS applications

In this work, a thin-film packaging was developed
to be used for radio-frequency microelectromechanical
system configurations. The fabricated packages are
suspended membranes in the multilayer SixNy/aSi/SixNy on
conductive coplanar waveguides (CPWs) of different
length. Several geometric parameters of the membranes,
which are the length, the curvature radius at the vertices of
the rectangular base, the density and the diameter of holes
on the capping surface, were also varied. The mechanical
properties of the suspended membranes were investigated
by mechanical simulations and surface profilometry measurements
as a function of the geometric parameters. RF
characterization was performed to evaluate the impact of
the package on the CPW performance. Finally, network
analysis was carried out, allowing to clarify the origin of
the RF losses measured for the fabricated microdevices.