Electromagnetic modelling of GaAs membrane supported mm-wave receivers

This paper presents a new electromagnetic modelling approach for the design of GaAs membrane supported monolithically integrated mm-wave receivers. The receivers structures are divided into membrane supported sections and bulk GaAs supported sections. Each block is modelled and designed using the full-wave electromagnetic simulation software Zeland IE3D. The Schottky diode is included in the model using the internal port feature. The design steps include the Schottky diode experimental characterization, design and measurements of membrane supported antenna demonstrators and linear/nonlinear simulations of the final receiver structures. The fabrication processes is based on GaAs micromachining. Two types of video detection receivers were designed, fabricated and tested: a 38 GHz double folded slot antenna receivers and a 45 GHz Yagi-Uda antenna receiver. Both circuits monolithically integrated the antenna with the Schottky diode on the same 2.2 μm thin semiinsulating GaAs membrane. The experimental results demonstrate an isotropic voltage sensitivity of 3000 mV/mW at 38 GHz and 6000 mV/mW at 45 GHz, respectively. The measurements validate the modelling approach and open a window of opportunity for the development of innovative RF MEMS architectures operating at higher frequency, up to the sub-millimetre wave frequency range