Abstract : Over the last 20 years, the industry of microelectronics and particularly the non-volatile memory market has known a considerable growth, in terms of integration capacity increasing and cost reduction. Consumers have been able to access to electronic products (mobile phones, MP3 players, flash drives, digital cameras...) which are currently very successful. However, scaling of standard Flash memories will face in a near future several limitations. Consequently, new paths are investigated in order to push the scaling limits of these devices. Within this context, the main purpose of this PhD is the experimental and theoretical study of nonvolatile silicon nanocrystal memories. First, several options of silicon nanocrystal integration using a standard process have been shown. A 32Mb NOR silicon nanocrystal Flash memory demonstrator has been fabricated from an ATMEL product. Then, electrical characterization of memory cells and arrays has been performed. An exhaustive study of the influence of programming conditions and technological parameters has been carried out. The influence of some parameters has been understood through modeling of Fowler- Nordheim erasing and gate disturb. Finally, the localization of the trapped charges in silicon nanocrystal devices written by Hot Electron injection has been investigated through TCAD simulations and an exhaustive set of experimental data explained by an analytical model.