Power module with directly attached thermally conductive structures
A power module includes a substrate having an electrically insulative member with opposing first and second metallized sides and one or more semiconductor die attached to the first metallized side of the substrate. A plurality of thermally conductive structures are laterally spaced apart from one another and individually attached directly to the second metallized side of the substrate so that the plurality of thermally conductive structures extend outward from the second metallized side.
1. A power module, comprising:
a substrate comprising an electrically insulative member with opposing first and second metallized sides;
one or more semiconductor die attached to the first metallized side of the substrate;
a housing covering the one or more semiconductor die;
a plurality of thermally conductive structures laterally spaced apart from one another and individually welded directly to the second metallized side of the substrate so that the plurality of thermally conductive structures extend outward from the second metallized side;
a cooler having a solid portion attached to the second metallized side of the substrate and a cavity so that the plurality of thermally conductive structures extend into the cavity and are laterally surrounded by the cooler; and
a sealing ring seated in a recess formed in the cooler, the sealing ring providing a seal between the cooler and the second metallized side of the substrate.
2. A power module according to claim 1 , wherein the housing is a plastic housing or a mold compound.
3. A power module according to claim 1 , wherein each thermally conductive structure has a length measured from the second metallized side of the substrate extending outward which ranges from 0.5 mm to 5 cm and a width which ranges from 0.1 mm to 3 mm.
4. A power module according to claim 3 , wherein the length of one or more of the plurality of thermally conductive structures is greater than the width.
5. A power module according to claim 3 , wherein the width of one or more of the plurality of thermally conductive structures is greater than the length.
6. A power module according to claim 3 , wherein the plurality of thermally conductive structures have at least one of variable lengths and variable widths.
7. A power module according to claim 1 , wherein each thermally conductive structure has a cylindrical, columnar or hexagonal shape.
8. A power module according to claim 1 , wherein a density of the plurality of thermally conductive structures is higher in a region of the second metallized side of the substrate corresponding to where each semiconductor die is attached to the first metallized side and lower elsewhere.
9. A power module according to claim 1 , wherein the substrate is a direct copper bonded substrate, a direct aluminum bonded substrate, an active metal brazed substrate, or a substrate with the first metallized side comprising copper and the second metallized side comprising aluminum.
10. A power module according to claim 1 , wherein the second metallized side and the plurality of thermally conductive structures each comprise a copper alloy.
11. A power module according to claim 1 , wherein the second metallized side and the plurality of thermally conductive structures each comprise an aluminum alloy.
12. A power module according to claim 1 , wherein the plurality of thermally conductive structures are individually attached directly to the second metallized side of the substrate in rows and columns in an aligned manner.