Mechanically driven SMR-based MEMS magnetoelectric antennas

Abstract

During different antenna miniaturization techniques, mechanically driven antennas have been demonstrated as the most effective method over state-of-the-art compact antennas. The magnetoelectric (ME) antennas based on a released magnetostrictive/piezoelectric heterostructure rely on electromechanical resonance instead of electromagnetic wave resonance, which results in a typical antenna size as small as one-thousandth of an electromagnetic wavelength. However, the microelectromechanical systems (MEMS) devices are very fragile and delicate due to their suspending structure. Here we show that solid mounted resonator (SMR)-based MEMS ME antennas can be realized with robust and high-gain performance. Although various packaging approaches are used to handle MEMS devices and protect them from environmental damage, these methods are complicated and high-cost. Compared to free-standing membrane ME antennas, SMR-based antennas are more structurally stable with no need for removing silicon substrate, but the design and fabrication of Bragg reflector layers must be carefully done to obtain the desired resonant frequency. In this work, 1D Mason model and 2D COMSOL finite element method (FEM) simulations were performed to design the SMR-based ME antennas. Then the in-plane radiation pattern of a fabricated antenna that operates at 1.75 GHz was characterized. Our results successfully demonstrate how to design, fabricate and test SMR-based ME antennas, which are provided with complementary metal-oxide-semiconductor (CMOS) process compatibility, size miniaturization, mechanical stability and high-gain performance. These miniaturized robust ME antennas are expected to have great influences on our future antennas for internet of things, wearable and bio-implantable applications, smart phones, wireless communication systems, etc.