A die is prepared for thermal compression bonding by first aligning electrical contacts on the die to bond pads on a substrate onto which the die is to be mounted. Those electrical contacts are held against the bond pads on the substrate with a bonding tool. Partially bonding the die onto the substrate by providing heat to a portion of the die to elevate a temperature there to above a melting point of solder in the electrical contacts so as to melt at least some of the solder. Then thermally compress the whole die and heat it to above the melting point of the solder of the electrical contacts so that the solder of the electrical contacts outside the portion of the die are also melted to bond the die to the substrate.