M.Sc Thesis

M.Sc StudentFeldman Shai
SubjectDesign, Fabrication and Characterization of a MEMS Based
DepartmentDepartment of Electrical and Computer Engineering
Supervisor PROFESSOR EMERITUS Yael Nemirovsky


The following Thesis presents a research activity containing the Design, Fabrication and Characterization of a Micro-electrical-Mechanical-system technology based switch. The switch is designed specifically for radio frequency (RF) waveguide structures targeted for the Ka band (26-40GHz) so as to enable a change between transmission and Isolation states.

In the design stage, an innovative design approach was investigated. The design concept was mainly based on a de-coupling approach between the switch actuator and the switching parts of the switch. In contrast to the popular Thin-film fabrication technology, bulk silicon, hybrid design was implemented. This approach enabled a more robust mechanical structure, that can improve electromechanical design and RF related features. Both a capacitive and a conductive shunt switch designs where implemented, based on the same layout and structure.

In the fabrication stage both a 50 Ohm CPW waveguide die and the complementary switch SOI based die were realized. Later on the hybrid assembly process of the switch and the waveguide was made possible by the usage of a flip-chip machine, forming an air gap of ~ 4 micron between switch metal plate and the CPW metal conductors.

The characterization stage included both mechanical (and electro-mechanical) parameters measurements, and a full RF circuitry test. The measured switches delivered a switching time in the area of 100micro-sec, under a 25-40Vdc actuation voltage. Regarding the RF parameters a very low insertion loss - smaller than 0.07 dB per switch (Open state) was achieved and isolation (close state) of greater than -18dB over the whole Ka target frequency band was measured.