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In this study, stereolithography of PZT films or composites has been successfully carried out. With regard to the PZT suspensions formulation, the process was modified to allow the deposition of films with thickness ranging between 8 to 40 μm. 1-3 and 0-3 piezocomposites as well as other highly loaded structures (maximum 45 % in volume) have been elaborated. Moreover, PZT thick films have been deposited on metallic substrates and silicon wafers. After sintering, crack-free PZT films with thickness ranging between 12 to hundreds of microns have been metallized and polarized. The properties of these microstructures have been studied with permittivity and piezoelectric coefficients measurements. Experiments have shown that the piezoelectric properties of PZT ceramics fabricated by stereolithography are promising (d 33 up to 200 pC/N and g 33 greater than 30×10 -3 Vm/N), which implies that such structures could be integrated in MEMS for microactuators or sensors applications. Finally, simultaneous fabrications by conventional stereolithography of polymer micropumps and their related piezoelectric transducers have been tested. The upper polymer membrane of the micropump is 100 μm thick and the inner diameter of the pump is 5 mm. Researches are in progress to improve the micropump flow rate and to manufacture a drop-on-demand inkjet device.

Laser stereolithography deals with the manufacture of 3D objects that are made by space-resolved laser-induced polymerization. In order to obtain 3D micro-objects, we developed a new microstereolithography apparatus based on the use of a dynamic mask generator which allows the manufacture of a complete layer by only one irradiation, the part being manufactured layer by layer. This process is compared of a broad-band visible light source, that leads to the elimination of speckle effects resulting from the conventional use of a laser beam, and of a liquid crystal display as the dynamic mask generator. A lateral resolution of 2 micrometers has been demonstrated, and some examples of high aspect ratio micro-objects are presented.