Microelectronic assembly having a heat spreader for a plurality of die

A microelectronic assembly, comprising:

• a heat spreader having a first major surface and a second major surface opposite the first major surface;
• at least one die located with respect to the first major surface of the heat spreader and thermally coupled to at least a portion of the heat spreader;
• at least one other die located with respect to the second major surface of the heat spreader and thermally coupled to at least a portion of the heat spreader;
• a plurality of openings in the heat spreader, each opening located in a region of the heat spreader between the at least one die and the at least one other die;
• a solid insulator located in at least one opening;
• and
• electrically conductive material located in an electrically insulated through hole in the solid insulator,
• wherein the solid insulator electrically isolates the electrically conductive material and the heat spreader from each other.

A microelectronic assembly, comprising:

• a heat spreader having a first major surface and a second major surface opposite the first major surface;
• at least one die located with respect to the first major surface of the heat spreader and thermally coupled to at least a portion of the heat spreader;
• at least one other die located with respect to the second major surface of the heat spreader and thermally coupled to at least a portion of the heat spreader;
• a plurality of openings in the heat spreader, each opening located in a region of the heat spreader between the at least one die and the at least one other die;
• an insulator comprising one of silicon dioxide, silicon nitride, and a non-electrically conductive polymer, located in at least one opening;
• and
• electrically conductive material located in an electrically insulated through hole in the insulator,
• wherein the insulator electrically isolates the electrically conductive material and the heat spreader from each other.