Patent ID: 8556158

Claim:
A method comprising: placing a first plurality of work pieces into work piece holders of a substrate carrier; picking up and placing a second plurality of work pieces, with each of the second plurality of work pieces being placed on corresponding ones of the first plurality of work pieces; bringing the first plurality of work pieces in contact with a first heating tool, wherein the first heating tool is integral with the substrate carrier; heating the first plurality of work pieces with the first heating tool; bringing the second plurality of work pieces in contact with a second heating tool and heating the second plurality of work pieces with the second heating tool, the second heating tool being configured to apply a force on the second plurality of work pieces and being different than the first heating tool; and reflowing a first plurality of solder bumps between the first and the second plurality of work pieces to form a second plurality of solder bumps and bond the first and the second plurality of work pieces together.