An apparatus includes a tool head configured for bonding to establish 100 or more electrical and mechanical connections between a silicon chip having a thickness of about 50 microns (μm) or smaller and a substrate, wherein 100 or more solder bumps set on a plurality of contacts on the silicon chip or a plurality of contacts on the substrate are melted by heating between the plurality of contacts of the silicon chip and the substrate, and wherein the melted solder bumps are solidified by cooling using forced convection of air flowing from around the silicon chip. The tool head includes a pyrolytic graphite sheet configured to be used in direct contact with the silicon chip, and having a thickness between about 75 μm and 125 μm.