Integrated MEMS Supercapacitor

RT&LFOCUS AREA(S): Microelectronics TECHNOLOGY AREA(S): Sensors, Electronics and Electronic Warfare OBJECTIVE: Develop an integrated MEMS supercapacitor for energy harvesting applications: material development for a MEMS supercapacitor, and its microfabrication process development DESCRIPTION: Research and development of self-powered electronics using energy harvesting techniques (vibrational, chemical) has increased recently to create portable monitoring devices for the defense, automotive, medical and consumer industries. Efficient energy storage is critical in for self-powered devices to be practical. For energy storage devices, energy density and power density are the two key parameters. Batteries normally have high energy density, but poor power density. The reverse is true for capacitors. Supercapacitors have the potential for both high energy and power density. There are many types of supercapacitors, they can be classified by their charge storage mechanisms: electric double layer capacitor (EDLC), electrochemical pseudo capacitor (EPC) and hybrid. Each type has different electrode materials. PHASE I: Perform a study to evaluate the feasibility, challenges and tradeoffs of the various MEMS supercapacitor technologies and electrode materials. Also compare equipment and development costs, as well as electrical tradeoffs of the supercapacitor when recommending a specific MEMS technology/electrode material for the application of energy storage of self-powered devices. Propose a MEMS supercapacitor which would include a materials development for a MEMS supercapacitor, and microfabrication process development PHASE II: Process integration and device fabrication of the supercapacitor prototype, including any optimization necessary. Test and characterization of the supercapacitor device. PHASE III DUAL USE APPLICATIONS: In addition to benefitting self-powered electronics applications, super-capacitors can also be used to improve the current handling of today's batteries, and used to enhance peak-load performance. Potential Value to DoD: This technology when proven, could allow for the further development of self-powered electronics within the DoD. DMEA, as the sole surviving DOD IC fabrication facility has been establishing itself as a center of excellence for innovative IC fabrication tools and techniques. Understanding of the challenges and tradeoffs in both supercapacitors and for a MEMS device development, will give DMEA valuable experience in supporting the DoD in this leading-edge technology. REFERENCES: Norman Tien, et al, The Future of MEMS in Energy Technologies ICSICT Nov 2008 YQ Jiang, et al, Planar MEMS Supercapacitor using Nanotube Forests ICMEMS Jan 2009 Swati Patil, et al, Status Review on the MEMS-based Flexible Supercapacitors Journal of Micromechanics and Microengineering, v29, n 9 Majid Beidaghi and Yury Gogotsi, Capacitive Energy Storage in Mirco-scale Devices: Recent Advances in Design and Fabrication of Micro-supercapacitors , Energy & Environmental Science, 2014, Issue 3