A dielectric wafer has, on top of its front face, a front electrical connection including an electrical connection portion. A blind hole passes through from a rear face of the wafer to at least partially reveal a rear face of the electrical connection portion. A through capacitor is formed in the blind hole. The capacitor includes a first conductive layer covering the lateral wall and the electrical connection portion (forming an outer electrode), a dielectric intermediate layer covering the first conductive layer (forming a dielectric membrane), and a second conductive layer covering the dielectric intermediate layer (forming an inner electrode). A rear electrical connection is made to the inner electrode.