Patent ID: 8308052

Claim:
A method comprising: heating a package structure comprising a first work piece and a second work piece to melt a plurality of solder bumps between the first and the second work pieces; and after the step of heating, allowing the plurality of solder bumps to solidify, wherein the method further comprises: during the step of solidifying, maintaining a first side of the package structure at a first temperature higher than a melting temperature of the plurality of solder bumps, wherein the step of maintaining is performed using a heating source; and during the step of solidifying, maintaining a second side of the package structure at a second temperature lower than the melting temperature by using a cooling source, wherein the second side is opposite the first side; and isolating a top side and a bottom side of the package structure from each other using a thermal isolation plate, wherein the heating source is configured to blow hot air from a first one of the top side and the bottom side and wherein the cooling source is configured to blow cold air from a second one of the top side and the bottom side when the package structure is placed through an opening in the thermal isolation plate.