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The thermoelectric effect can be defined as the power that can be ascribed to the results of the temperature gradient
across a junction between two different metals. Micro thermoelectric generators (μTEGs) are used with energies or
losses that have a gradient in temperature or spatial dimensions that are too small for conventional thermodynamic
heat engines to effectively utilize, delivering micro-Watts to milli-Watts of power per device. Silicon nanowires
(SiNW) thermoelectrical properties are more enhanced compared to thin-layer silicon, mainly due to the decrease of
thermal conductivity caused by the quantum confinement and phonon scattering effects in low dimensions. SiNWs as
a thermoelectric material is also very advantageous due to the abundance of silicon as raw material and its ability to
be produced by regular IC manufacturing techniques leading to low cost. Here, our present works show a portable and
autonomous power generation microsystem based on a SiNWs μTEG coupled with an infrared plasmonic absorber for
heat-trapping purposes capable of powering micro/nano system.
One of the major sources of harvesting energy for the μTEGs is the human skin which is presented in our work. The
μTEG is integrated with a micro silicon-based plasmonic IR absorber plate in order to harvest thermal energy in the
IR regime. This enhanced μTEG/absorber hybrid exhibited an increased ability to trap minimum excess heat on its
surface owing to the IR absorber, resulting in a considerable enhancement in output power and conversion efficiency
when compared to a standard μTEG. In this work, full simulations of the absorber are performed in addition to
electrical and thermal simulations for the μTEG by using COMSOL Multiphysics Simulator. The integrated hybrid
microsystem is easily fabricated using standard CMOS processes and has many applications, such as the powering of
wireless sensors and the harvesting of lost heat from electronic components.
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