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Pyroelectric generators (PEGs) can be used for thermal energy harvesting and present a potential alternative to thermoelectric generators. However, in contrary to thermoelectric generators, the PEG principle requires thermal transients to stimulate the conversion process. Such suitable thermal transients are rare in nature, hindering the deployment. In this paper, we present a micro thermomechanic-pyroelectric energy generator (μTMPG) that converts a stationary spatial thermal gradient into the required transient temperature profile across the PEG. The measured power output of the μTMPG is 3 μW from a temperature difference of 79.5 K. However, with an optimized design, a power output of 39.4 mW is estimated for the same temperature difference.

A full-wafer process is presented for fast and simple fabrication of glass microfluidic chips with integrated electroplated electrodes. The process employs the permanent dry film resist (DFR) Ordyl SY300 to create microfluidic channels, followed by electroplating of silver and subsequent chlorination. The dry film resist is bonded directly to a second substrate, without intermediate gluing layers, only by applying pressure and moderate heating. The process of microfluidic channel fabrication, electroplating and wafer bonding can be completed within 1 day, thus making it one of the fastest and simplest full-wafer fabrication processes.

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This paper presents a micro heat engine fabricated in silicon micro technology. Its operation principle is based on a cavity filled with a liquid-gas phase-change working fluid that performs a self-controlled reciprocating motion between a heat source and a heat sink. A bistable buckling membrane generates the respective upward and downward driving forces upon expansion and contraction of the working fluid. For prediction of the engine performance a hybrid model is developed. This model predicts an operation frequency of 0.72 Hz and a mechanical output power of 1.29 μW at a temperature difference of 37 K. Loss mechanisms are theoretically explored and ways to enhance the overall engine efficiency are discussed. To verify this model, a functional demonstrator is fabricated. In the experiments, an operation frequency of 0.71 Hz is found at a temperature difference of 37 K.

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