The technique described herein includes a device to address the electrical performance (e.g. signal integrity) degradation ascribed to electromagnetic interference and/or crosstalk coupling occur at tightly coupled (e.g. about 110 μm pitch or less) interconnects, including the first level (e.g. the interconnection between a die and a package substrate). In some embodiments, this invention provides a conductive layer with a plurality of cavities to isolate electromagnetic coupling and/or interference between adjacent interconnects for electronic device performance scaling. In some embodiments, at least one interconnect joint is coupled to the conductive layer, and at least one interconnect joint is isolated from the conductive layer by a dielectric lining at least one of the cavities, the conductive layer being associated to a ground reference voltage by the interconnect joint coupled to the conductive layer.