Semiconductor die package with increased thermal conduction

A method for fabricating a structure for receiving a semiconductor die, said method comprising steps of:

• fabricating a substrate having a core and a core thickness, a top surface and a bottom surface;
• forming a substrate die pad on said top surface of said substrate;
• forming a heat spreader on said bottom surface of said substrate;
• forming at least one buried via in said core of said substrate;
• forming a first metal cap situated below and thermally coupled to said substrate die pad, said first metal cap situated above said at least one buried via;
• and
• forming a second metal cap situated below said at least one buried via, said at least one buried via providing a connection between said substrate die pad and said heat spreaders;
• said at least one buried via formed with a length substantially corresponding to said core thickness.

A structure comprising:

• a multilayer substrate having a core and a core thickness, a top surface and a bottom surface;
• a substrate die pad situated on said top surface of said substrate;
• a die fixed to said substrate die pad by an epoxy;
• a heat spreader situated on said bottom surface of said substrate, said substrate further comprising a first metal cap, at least one buried via, and a second metal cap, said first metal cap situated below and thermally coupled to said substrate die pad, said at least one buried via situated below said first metal cap and within said core, said second metal cap situated below said at least one buried via and thermally coupled to said heat spreader, said at least one buried via providing a connection between said substrate die pad and said heat spreaders;
• said at least one buried via having a length substantially corresponding to said core thickness.

A structure comprising:

• a multilayer substrate having a core, a top surface and a bottom surface;
• a substrate die pad situated on said top surface of said substrate;
• a heat spreader situated on said bottom surface of said substrate, said substrate further comprising a first metal cap, at least one buried via, and a second metal cap, said first metal cap situated below and thermally coupled to said substrate die pad, said at least one buried via situated below said first metal cap and within said core, said second metal cap situated below said at least one buried via and thermally coupled to said heat spreader, said at least one buried via providing a connection between said substrate die pad and said heat spreader;
• the substrate further comprising
• a first intermediate metal layer situated between and thermally coupling said first metal cap and said at least one buried via,
• a second intermediate metal layer situated between and thermally coupling said at least one buried via and said second metal cap,
• a third layer situated between said substrate die pad and said first intermediate metal layer, said first metal cap occupying a portion of said third layer,
• a fourth layer situated between said heat spreader and said second intermediate metal layer! said second metal cap occupying a portion of said fourth layer.

A method for fabricating a structure for receiving a semiconductor die, said method comprising steps of:

• fabricating a substrate having a core, a top surface and a bottom surface;
• forming a substrate die pad on said lop surface of said substrate;
• forming a heat spreader on said bottom surface of said substrate;
• forming at least one buried via in said core of said substrate;
• forming a first metal cap situated below and thermally coupled to said substrate die pad, said first metal cap situated above said at least one buried via;
• forming a second metal cap situated below said at least one buried via, said at least one buried via providing a connection between said substrate die pad and said heat spreader:
• laminating over said first metal cap with a first laminating material comprising a first resin coated foil layer, thereby causing said first foil layer to directly contact said first metal cap.