An electronic device has a rear plate that includes a substrate rear layer, a substrate front layer and a dielectric intermediate layer between the substrate rear and front layers. An electronic structure is on the substrate front layer and includes electronic components and electrical connections. The substrate rear layer includes a solid local region and a hollowed-out local region. The hollowed-out local region extends over all of the substrate rear layer. The substrate rear layer does not cover at least one local zone of the dielectric intermediate layer corresponding to the hollowed-out local region.