Method for forming a semiconductor device assembly having a heat spreader
A method includes providing an integrated circuit (IC) die assembly that includes a substrate and an IC die mounted on a portion of a major surface of the substrate, dispensing an interface material on the IC die, positioning a portion of a heat spreader in contact with the interface material, and dispensing an adhesive between one side of the heat spreader facing the IC die assembly and exposed portions of a major surface of an encapsulant on the substrate.
1. A method comprising:
providing an integrated circuit (IC) die assembly that includes a substrate and an IC die mounted on a portion of a major surface of the substrate;
dispensing a thermal interface material on the IC die;
positioning a portion of a heat spreader in contact with the thermal interface material; and
after the positioning the portion of the heat spreader in contact with the thermal interface, dispensing an adhesive between one side of the heat spreader facing the IC die assembly and exposed portions of a major surface of an encapsulant on the substrate wherein the dispensing the adhesive is performed so that the adhesive is in contact with the major surface of the encapsulant on the substrate and at least a portion of the one side of the heat spreader.
2. The method of claim 1 , further comprising curing the adhesive.
3. The method of claim 1 , further comprising curing the adhesive and the interface material.
4. The method of claim 1 , wherein the dispensing the adhesive is dispensed around edges of the heat spreader.
5. The method of claim 1 , wherein the heat spreader includes:
a pedestal that contacts the thermal interface material, and
at least one vent through the heat spreader around an outer perimeter of the pedestal.
6. The method of claim 4 , wherein the dispensing the adhesive is performed using a nozzle that dispenses the adhesive through the vent of the heat spreader.
7. The method of claim 1 , wherein the portion of the heat spreader in contact with the interface material is a downset portion, the downset portion is positioned over the IC die inside a perimeter of wire bonds attached between the IC die and the substrate.
8. A method comprising:
attaching a semiconductor die to a substrate;
forming wire bonds between the die and the substrate;
encapsulating the wire bonds with a mold compound, wherein the mold compound is configured to expose a top surface of the die that does not include the wire bonds;
after the encapsulating, applying a first adhesive over the top surface of the die;
after the applying the first adhesive, contacting a portion of a heat spreader to the first adhesive; and
dispensing a second adhesive so that the second adhesive fills a gap between a first side of the mold compound and a first side of the heat spreader.
9. The method of claim 8 , wherein the contacting the portion of the heat spreader includes applying pressure to between the heat spreader and the substrate to establish a predetermined thickness of the first adhesive.
10. The method of claim 8 , wherein the first adhesive is a thermal interface material and the second adhesive is a material flowable by capillary action.
11. The method of claim 8 , wherein the dispensing the second adhesive includes dispensing the second adhesive around a perimeter of the heat spreader so that the second adhesive flows in the gap and is in contact with the first side of the mold compound and the first side of the heat spreader.
12. The method of claim 8 wherein the heat spreader includes a vent through a cross-section that is outside the portion of the heat spreader that is in contact with the first adhesive.
13. The method of claim 12 , wherein the dispensing the second adhesive includes dispensing the second adhesive in the vent so that the second adhesive flows in the gap and is in contact with the first side of the mold compound and the first side of the heat spreader.
14. The method of claim 8 , further comprising curing the first and second adhesives.
15. The method of claim 12 , wherein the portion of the heat spreader that is in contact with the first adhesive is a downset portion that extends toward the die from the first side of the heat spreader.
16. A method comprising:
applying a first interface material on an exposed portion of an integrated circuit (IC) die mounted on a substrate;
mounting a first portion of a heat spreader on the IC die using an interface material, the heat spreader having an opening through a second portion of the heat spreader that is outside of the first portion of the heat spreader, wherein the heat spreader has a first major surface facing the IC die and a second major surface opposite the first major surface, and wherein the opening extends through the first and second major surfaces of the heat spreader; and
dispensing an adhesive between a first side of the heat spreader and a surface of an encapsulant on the substrate, wherein the interface material is different than the adhesive.
17. The method of claim 16 , wherein the interface material has one of a group consisting of: different thermal properties than the adhesive and different mechanical properties than the adhesive.
18. The method of claim 16 , wherein the adhesive is dispensed by one of a group consisting of: around an edge of the heat spreader, and through the opening of the heat spreader.
19. The method of claim 16 , further comprising using capillary action to move the adhesive between the encapsulant and the first side of the heat spreader.