Electrostatic parallel-plate MEMS switch on silicon-ceramic-composite-substrates

In this work we will present the capabilities of this monolithic SiCer (silicon on ceramics) compound by producing a parallel-plate RF-MEMS switch with flexible electrodes and integrated coplanar waveguides. The series switch is one part of a LTE demonstrator and is developed in a heterogeneous process design. Here, the aim is to create a low-voltage switch for mobile use with a simple layout. The modelling and simulation of the parallel-plate switch with flexible electrodes is carried out using ANSYS (electro-mechanical simulation) and CADENCE (circuit simulation). To demonstrate the advantages of the composite substrate, the coplanar waveguides for the RF-signal and the control lines for the actuation of the electrostatic parallel plates of the switch are processed by screen printing them on the LTCC tapes before sintering the composite. The relocation of the waveguides into the LTCC avoids damping influences on RF signals by the silicon. An optimal process flowchart for modifying the silicon surface is shown through which bond areas with a homogeneous bond strength between silicon and LTCC are achieved and certain areas with cavities at the bond interface can be produced.