Method of collective fabrication of 3D electronic modules, each 3D electronic module comprising a stack of at least two, surface transferable, ball grid electronic packages, tested at their operating temperature and frequency, which comprises: - a step of fabricating reconstituted wafers, each reconstituted wafer being fabricated according to the following sub-steps in the following order: ∘ A1) the electronic packages are placed on a first sticky skin, balls side, ∘ B1) moulding of the electronic packages in the resin and polymerization of the resin, to obtain the intermediate wafer, ∘ C1) thinning of the intermediate wafer on the face of the intermediate wafer opposite to the balls, ∘ D1) removal of the first sticky skin and placing of the intermediate wafer on a second sticky skin, side opposite to the balls, ∘ E1) thinning of the intermediate wafer on the balls side face, or a step of removing the balls of said electronic packages prior to the step of placing the electronic packages on the first sticky skin, ∘ F1) formation of a balls side redistribution layer, ∘ G1) removal of the second sticky skin to obtain a reconstituted wafer of smaller thickness than the original thickness of the electronic packages, - several reconstituted wafers having been obtained on completion of the previous sub-steps, stacking of the reconstituted wafers, - dicing of the stacked reconstituted wafers to obtain 3D modules. - a step of fabricating reconstituted wafers, each reconstituted wafer being fabricated according to the following sub-steps in the following order: ∘ A1) the electronic packages are placed on a first sticky skin, balls side, ∘ B1) moulding of the electronic packages in the resin and polymerization of the resin, to obtain the intermediate wafer, ∘ C1) thinning of the intermediate wafer on the face of the intermediate wafer opposite to the balls, ∘ D1) removal of the first sticky skin and placing of the intermediate wafer on a second sticky skin, side opposite to the balls, ∘ E1) thinning of the intermediate wafer on the balls side face, or a step of removing the balls of said electronic packages prior to the step of placing the electronic packages on the first sticky skin, ∘ F1) formation of a balls side redistribution layer, ∘ G1) removal of the second sticky skin to obtain a reconstituted wafer of smaller thickness than the original thickness of the electronic packages, ∘ A1) the electronic packages are placed on a first sticky skin, balls side, ∘ B1) moulding of the electronic packages in the resin and polymerization of the resin, to obtain the intermediate wafer, ∘ C1) thinning of the intermediate wafer on the face of the intermediate wafer opposite to the balls, ∘ D1) removal of the first sticky skin and placing of the intermediate wafer on a second sticky skin, side opposite to the balls, ∘ E1) thinning of the intermediate wafer on the balls side face, or a step of removing the balls of said electronic packages prior to the step of placing the electronic packages on the first sticky skin, ∘ F1) formation of a balls side redistribution layer, ∘ G1) removal of the second sticky skin to obtain a reconstituted wafer of smaller thickness than the original thickness of the electronic packages, - several reconstituted wafers having been obtained on completion of the previous sub-steps, stacking of the reconstituted wafers, - dicing of the stacked reconstituted wafers to obtain 3D modules.