Piezoelectric materials utilisation for hybrid and monolithic integration of transformers
Works presented in this report concerns the problems of electric devices integration in general and passive components integration in particular aiming to carry out the realization of integrated conversion systems. In a first part, the study and the characterization of piezoelectric transformers exhibiting millimetre-length is tackled for supply of fractions of Watts to few Watts applications. This transformer is well adopted to MOSFET & IGBT gate drive circuits integrated on a PCB substrate. This application is fully detailed in the report. In a second part, we have been interested in the problem of integration of piezoelectric micro-transformers in a silicon substrate for supplying micro-systems. We have been proposed new micro-transformer structure realized with AlN and PZT thin layers deposed by sputtering. These manufacturing process are compatible with silicon technologies and with the constraints of micro-machining. An original prototype has been realized and characterized.