Discipline ou spécialité: Microélectronique

Full integration of energy conversion devices for compact power supply circuits is still encountering strong technological locks, especially to integrate passive inductive and capacitive components. The increasing working frequency of those devices, which already reaches 1 Megahertz, would enable the size reduction of passive components and then their integration. Nevertheless, losses, which highly depend on frequency and technology, may complicate or even stop this increase. The objective of this thesis is the systematic study of integrated inductors structures through the developing of precise modeling and simulating methods on the frequency range from 0Hz to 1GHz. First, an analytic model based on PEEC (Partial Element Equivalent Circuit) method has been developed. This modeling approach has been adapted to the studied components: rotational symmetry, not negligible section conductors, inhomogeneous media, etc... The final model splits the physical study of the component into two steps: electromagnetic computations on subparts of the set (partial elements) and global frequency response calculus with the equivalent electrical models of the subparts. A full process for the technological realization of inductive components has also been achieved in order to experimentally verify the modeling. The improvement of design resolution and increase of copper electroplating thickness, as planarization of conductor levels with SU8 resin have been specifically studied. Those overhangs have permitted the realization of multilevel and multiconductor inductors which present good features at high frequency. Finally, the characterization of prototypes at low frequency has been enabled by the realization of an impedance measurement bench we developed for the range from 40Hz to 110MHz and high frequency characterizations have been performed with a network analyzer. This work has been completed by the development of a very fast computing analytical model for the calculus of the magnetic field in integrated inductors. This method has been used to find the repartition of the magnetic field generated by integrated planar magnetic actuators excited by a DC current for a microsystems and microfluidics application.