Energy harvesting from nanostructures
Résumé
We present nanostructure based piezoelectric and thermoelectric energy harvesters. Using different forms of nanostructuration (heterostrucutration, composite materials, superlattices) further helps improving the performance of such nanodevices that could be used both as self-powered sensors and nanogenerators with IC compatibility. GaN and ZnO nanowires are used as piezoelectric devices. While a specific AFM method is used to investigate the individual nanowire properties, large area prototypes composed of nanowire arrays are realized to evaluate the performance of such nanogenerators. Bottom-up techniques using industrial tools are also used to grow Si/SiGe quantum dot superlattices, both n and p types, mono- or poly-crystalline to be used as thermoelectric elements where nanostructuration improves the ZT figure of merit. Going even further, for the first time we report the realization of Ti and Mo silicide quantum dot superlattices, both n an p type.