Lid attach process

1. A method of attaching a lid to a substrate having an integrated circuit positioned thereon, comprising:

applying an adhesive to the substrate;

applying an indium film to the integrated circuit;

positioning the lid on the adhesive;

partially hardening the adhesive while applying a compressive force to the lid;

reflowing the indium film without applying a compressive force to the lid; and

curing the adhesive without applying a compressive force to the lid.

2. The method of claim 1 , wherein the partial hardening is by heating.

3. The method of claim 1 , wherein the integrated circuit has a footprint, the step of applying the indium film comprises applying a sheet of indium having a footprint substantially matching the footprint of the integrated circuit.

4. The method of claim 1 , comprising heating the lid before positioning the lid on the adhesive.

5. The method of claim 1 , wherein the reflowing of the indium and the curing of the adhesive comprise heating.

6. The method of claim 1 , wherein the positioning of the lid on the adhesive comprises using an automated machine to pick and place the lid on the adhesive.

7. The method of claim 1 , comprising reflowing the indium film in a belt furnace.

8. A method of manufacturing, comprising:

flip-chip mounting an integrated circuit to a substrate whereby a backside of the integrated circuit faces away from the substrate;

applying an adhesive to the substrate;

placing a lid on the adhesive, the lid having an underside;

positioning an indium film between the backside of the integrated circuit and the underside of the lid;

partially hardening the adhesive to fix a bond line thickness of the indium film;

reflowing the indium film after the adhesive has been partially hardened; and

curing the adhesive.

9. The method of claim 8 , comprising providing the backside of the integrated circuit with a first wetting film and the underside of the lid with a second wetting film.

10. The method of claim 8 , wherein the partial hardening of the adhesive is performed while compressive force is applied to the lid.

11. The method of claim 8 , wherein the curing of the adhesive is performed without applying compressive force to the lid.

12. The method of claim 8 , wherein the reflowing of the indium and the curing of the adhesive comprise heating.

13. The method of claim 8 , comprising heating the lid before positioning the lid on the adhesive.

14. The method of claim 8 , comprising reflowing the indium film in a belt furnace.

15. The method of claim 8 , comprising reflowing the indium without applying compressive force on the lid.