Magnetostrictive Type Rf Mems Switch Performance Simulation And Preparation Process

In this thesis, the microwave characteristics and the mechanical behaviors of two kinds of typical structure MEMS switch -the cantilever and the bridge of the magnetostrictive RF MEMS switches -have been simulated by HFSS5.6 and ANSYS7.0 software respectively. These two kinds of MEMS switches have been fabricated with the method of the surface machining and bulk machining, and the fabrication processes have been studied. The influences of the structure parameters such as the distance between the signal lines (d), the width of the signal line (w), the height of the air gap (g), the area of the contacting layer (A) of the cantilever switch, and the width of the membrane (wb), the width of the signal line (w), the height of the membrane (hg) of the bridge switch on the microwave characteristics of the cantilever and the bridge MEMS switches, have been simulated respectively. The results show that the cantilever MEMS switch with the dimensions of d of 25μm,w of 30μm,g of 2μm,A of 150×60μm2, and the bridge MEMS switch with the dimensions of wd of 50μm,w of 100μm,hg of 2.0μm have the microwave characteristics of insertion loss smaller than 0.2dB and isolation larger than 35dB within the frequency range of 1.1±0.2GHz, which satisfied with the design demand. The influences of the width of the cantilever (W), the length of the cantilever (L), the substrate material and the substrate thickness (Ts) of the cantilever, the thickness of the magnetostrictive film (Tf), and the length of the bridge on the deflections (D) of the cantilever and the bridge MEMS switch have been studied respectively. The results show that the deflection of the cantilever increases with the increase of the length of the cantilever, which follows the rule of D∝L2, and decreases with the increase of the Ts. The deflection of the cantilever MEMS switch is insensitively to the width of the cantilever, but increases with the increase of the Tf firstly and decreases with the further increase of the Tf. The deflection of the bridge MEMS switch increases with the increase of the length of the bridge. The fabrications of the MEMS switch are based on the surface machining and the bulk machining technologies. The magnetron sputtering, photolithography, chemical etching and plasma etching have been used. The key processes of the experiments have been studied and discussed. After the feasible processes have been decided, the...