SBIR Phase I: Magneto-electric-MEMs-enabled Wireless Power for Medical Implants

Ferro Solutions, Inc., Woburn MA

Investigators

Abstract

This Small Business Innovative Research (SBIR) Phase-I project will develop micro-electro-mechanical-systems (MEMS) comprised of engineered magneto-electric (ME) materials to enable wireless power transfer systems for medical implants. Engineered ME materials are composites of magnetostrictive (M) and electro-active (E) components that convert magnetic fields into voltages much more efficiently than do natural MEs. Incumbent wireless power technologies rely on coils to convert time-dependent magnetic fields, generally at radio frequencies, into useful power. Bulk ME receivers, though not yet optimized, show increasing sensitivity advantages over comparable-size, high-permeability coil receivers as frequency and/or device size decreases. A series of several dozen generic MEMS resonators (cantilevers, bridges, plates in different sizes and aspect ratios) were designed with high-Q, epitaxial piezoelectric films grown on single-crystal substrates. Phase I of the new program includes characterizing the mechanical integrity and resonance characteristics of the piezoelectric MEMS substrates. Photo-resist masks for selected devices will be designed to allow deposition of M films on the piezoelectric resonators to create generic ME-MEMS devices. These devices will be packaged and tested for received power-per-unit-magnetic-field at different frequencies and field strengths. Data will be analyzed and compared with that for bulk ME and coil devices. The broader impact/commercial potential of this project should extend well beyond development of smaller and more efficient wireless power systems for implanted medical devices. High-performance ME wireless power receivers have not yet been made at the MEMS scale. This research program will develop new thin film processing techniques for deposition of high Q amorphous magnetic films and CMOS-compatible, piezoelectric films on each other that would impact many technical markets including magnetic and/or acoustic sensors, communications systems capable of operation in environments that hinder conventional radio transmission, and possibly new multifunctional components for intelligent electronic systems. Successful development of ME-MEMS receivers will enable a variety of engineered ME devices, such as: i) magnetometers that could rival SQUID magnetometers in sensitivity while consuming far less power and operating at room temperature rather than L-He temperatures, ii) systems for low-frequency communications in high-absorption environments where RF systems fail; iii) advanced processes for co-deposition of magnetic and electro-active films, enabling new applications of multi-functional ME-MEMS devices.