US 12,336,148 B2
Thermal management solution for power stage comprising top-cooled power semiconductor switching devices
Ruoyu Hou, Kanata (CA); and Juncheng Lu, Kanata (CA)
Assigned to GaN Systems Inc., Kanata (CA)
Filed by GaN Systems Inc., Kanata (CA)
Filed on Mar. 10, 2023, as Appl. No. 18/120,046.
Prior Publication US 2024/0306348 A1, Sep. 12, 2024
Int. Cl. H05K 7/20 (2006.01); H01L 23/367 (2006.01); H05K 1/02 (2006.01); H05K 1/18 (2006.01)
CPC H05K 7/20409 (2013.01) [H01L 23/3672 (2013.01); H05K 1/0216 (2013.01); H05K 1/185 (2013.01); H05K 2201/066 (2013.01); H05K 2201/10166 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A power stage assembly for top-cooled semiconductor power switching devices comprising:
a PCB substrate
a plurality of embedded die packages, each die package comprising a semiconductor power switching device comprising at least one power transistor, having electrical contact areas on a front-side of the embedded die package and a thermal pad on the back side of the embedded die package;
the plurality of embedded die packages being mounted on the PCB substrate with electrical connections between conductive traces of the PCB and the electrical contact areas on the front-side of each die package;
a heat-spreader in thermal contact with the thermal pads on the back-side of each die package; the heat-spreader being secured to the PCB substrate; and a heatsink in thermal contact with the heat-spreader;
wherein the heat-spreader is a multilayer structure comprising:
a first layer comprising a thermally conductive metal substrate layer in contact with the heatsink;
a second layer comprising a thermally conductive dielectric layer;
a third layer comprising an electrically conductive and thermally conductive material defining an electromagnetic compatibility (EMC) shielding layer;
a fourth layer comprising a thermally conductive dielectric layer;
a fifth layer comprising an electrically conductive and thermally conductive material defining thermal pads in thermal contact with thermal pads of each die package;
the dielectric layers providing electrical isolation between said conductive layers; and the EMC shielding layer being interconnected to power ground; and the thermal pads of the fifth layer having an area larger than an area of the thermal pad of each embedded die package to provide lateral heat-spreading.