C2N (Centre de Nanosciences et de Nanotechnologies, UMR 9001, 450 persons) activity focuses on Nanomaterials, Nanophotonics, Nanoelectronics and Microsystems. It hosts one of the largest academic cleanrooms in Europe (2900 sq.m) dedicated to micro and nanofabrication processes, to the growth, the epitaxy and the characterization of materials. It employs 40 engineers and technicians, and to date more than 50 M€ are invested in state-of-the-art equipment for micro-nanotechnologies. In FIESTA, C2N is in charge of the integration of the active materials developed at FEMTO-ST into dedicated structures designed with LGEF and ELyTMaX. C2N has also a recognized expertise in interfacing electrostatic and piezoelectric devices and contributes with LGEF to the design and implementation of specific circuits optimized for the targeted energy conversion cycles.