Patent ID: 7497366
Filing Date: 2009-03-03
Classification: B23K,H01L

Abstract:
1. A method of injection molding solder into a plurality of cavities in a circular mold, the method comprising: placing at least a circular mold and a fill head within a vacuum chamber, wherein the circular mold includes a plurality of cavities, and wherein the fill head is slightly longer than a diameter of the circular mold, the fill head being configured to provide conductive bonding material to the plurality of cavities bi-directionally, and further wherein the fill head comprises a substantially curved configuration substantially matching a curvature of a perimeter of the circular mold, the fill head being aligned relative to a radius of the circular mold; creating a vacuum within the vacuum chamber, thereby removing air within the chamber and in the plurality of cavities; placing the fill head in substantial contact with the circular mold; providing rotational motion to the fill head while the fill head is in substantial contact with the circular mold, and wherein the rotational motion provides a relative rotation of substantially up to 180 degrees between the fill head and the circular mold to provide the solder into the plurality of cavities; forcing solder out of the fill head toward the circular mold; providing the solder into the plurality of cavities contemporaneous with the plurality of cavities being in proximity to the fill head; activating a heating member in the fill head, the heating member having a temperature above a melting point of the solder thereby maintaining the solder in a molten state as the solder and the heating member are in close proximity to one another; channeling a cooling gas about a trailing edge of the fill head, the cooling gas having a temperature below the melting point of the solder thereby substantially solidifying the solder within at least one cavity of the plurality of cavities as the at least one cavity passes under the trailing edge of the fill head with cooling gas; lifting the fill head off of the circular mold after the solder is provided into the plurality of cavities; receiving temperature feedback from at least one thermocouple situated within the fill head; and transitioning the fill head from the circular mold, the fill head passing over an adapter coupled to the circular mold, to an adjacent circular mold as the fill head transitions from the circular mold to the adjacent circular mold thereby preventing spillage of solder from the transitioning fill head.