Centre for Radiofrequencies, Optic and Micro-nanoelectronics in the Alps
PhD Defense of ROCHEFEUILLE Edouard
Characterizations and evolutions of RF energy harvesting structures on Si and SOI substrates: application to manage microwatt energy systems
Monday, July 12, 2021 at 2pm
Abstract:
Advances in microelectronics and integrated technologies have allowed the evolution and growth of the world of nomadic connected objects. However, these wireless devices require power, maintenance, access and autonomy. Thus, in order to make these devices completely autonomous, this thesis proposes the study of a circuit participating in the power supply of these connected objects using integrated technologies with as source Radiofrequency (RF) Energy Harvesting at 2.45 GHz.
The confrontation between two integrated technologies is presented: a more recent one, the FDSOI 28 nm and the other more known and standard, the BULK 350 nm. To achieve the power supply function, an RF energy rectifier circuit (rectenna) is associated with a voltage boost circuit known as a charge pump. The polarization of the substrate in FDSOI technology shows that an improvement in rectification performance can be envisaged. This makes it possible to respond to the problem: do the new integrated technologies make it possible to create sufficiently high-performance circuits to participate in the supply of wireless sensors thanks to RF Energy Harvesting? First of all, our simulation work highlights the fact that the FDSOI technology, thanks to the substrate polarization, allows the reduction of the threshold voltage of the transistor and therefore increases the output voltage of the rectifier (transistor mounted in diode). Second, circuits are dimensioned using a method of parametric analysis simulations. Finally, after taking into account parasitic effects resulting from post-layout simulations, two sets of chips in each technology are produced. The simulation and measurement results indicate that the adopted methodology contributes to the power supply of a sensor such as the TelosB in its standby phase using RF Energy Harvesting and the proposed circuit topologies. However, the assembly of the various circuits has not been approached in this thesis and constitutes a line of thought for future work as well as being able to couple the RF energy used as power to also supply information..
Jury members :
Mr. Pascal XAVIER, Professor :President
Mr. Bruno ALLARD, Professor : Reviewer
Mme. Nathalie DELTIMPLE, H.D.R: Reviewer
Mme. Nathalie RAVEU, Professor : Examiner
Mr. Pierre-Olivier LUCAS-DE-PESLOUAN, MCF : Examiner
Mr. Tân-Phu VUONG, Professor : Supervisor
Mr. Frédéric ALICALAPA, MCF : Co-Supervisor
Mr. Alexandre DOUYÈRE, MCF : Co-Supervisor
Partenaires
Thesis prepared in the laboratory IMEP-LaHC (Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et de Caractérisation) supervised by Pr. Tân-Phu VUONG.