Semiconductor device socket and semiconductor device connecting method using anisotropic conductive sheet

A semiconductor device socket, in which a semiconductor device is installed, includes a support member on which a substrate is placed, an anisotropic conductive sheet that acts as an intermediary in electric connection between the substrate and the semiconductor device, and heater which heats the anisotropic conductive sheet. The heater heats the anisotropic conductive sheet for expanding the sheet before the semiconductor device is installed in the semiconductor device socket. The semiconductor device is installed in the socket after the anisotropic conductive sheet has been expanded by heat from the heater.