GaAs micromachining for millimeter wave applications

This paper presents the fabrication processes for micromachined millimeter wave devices on micromachined GaAs substrates. The 2.2 /spl mu/m thin GaAs/AlGaAs membrane, obtained by MBE growth and micromachining of semi-insulating <100> GaAs, is used as support for millimeter wave filter structures. Cascaded coplanar waveguide open-end series stubs filter type structures, with central frequencies of 38 and 77 GHz, as well as monolithic integrated millimeter wave receivers were designed and manufactured on GaAs micromachined substrates.