Embodiments of the disclosure relate to an electronic assembly including a substrate having a first surface and a second surface opposite to the first surface and one or more electronic devices bonded to the first surface of the substrate. A first heat-storing region is embedded within the substrate and proximate to the second surface. The first heat-storing region comprises a phase change material encapsulated by an encapsulating layer. A melting temperature of the encapsulating layer is higher than a melting temperature of the phase change material and a maximum operating temperature of the one or more electronic devices. A heat transfer layer is embedded within the substrate and thermally connects the first heat-storing region to the one or more electronic devices.