Modeling of an Integrated Electromagnetic Generator for Energy Scavenging

The ubiquitous deploying of wireless electronic devices due to pervasive computing results in the idea of Energy Scavenging, i.e., harvesting ambient energy from surroundings of the electronic devices. As an approach to possible practical realization of such an energy scavenger, we aim at the fabrication of an electromagnetic (EM) generator. The generator will be fully on-chip integrated, CMOS compatible, suitable for silicon post-processing, and will have a natural resonant frequency below 100 Hz. To the best of our knowledge, such an EM generator will be the first fully on-chip integrated energy harvester. We have designed an integrable EM generator and have developed a process flow entirely based on low temperature post-processing technology. Our EM generator is composed of a permanent micro-magnet, a spring, and copper coils. The resonant frequency of the generator will be tuned by the spring constant k and the mass of the magnet. The AC/DC module of COMSOL software was used to perform numerical simulations in order to determine optimal relative dimensions of the generator and the best possible position of the permanent micro-magnet with respect to the copper coils. Keywords: CMOS post-processing, electromagnetic generator, energy scavenging, deposition, micromachining, permanent magnet