US Patent 7307224 Semiconductor device having a mount board

A semiconductor device includes a memory module board mounting thereon a plurality of DRAM devices, and a mount board mounting thereon the memory module board via a combination of socket and plug. The socket formed on the mount board has a pair of heat radiation guide plates attached onto the side surfaces of the socket. The heat radiation plates have a thermal conductivity of 1 watt/meter·K. The surface of the mount board onto which the socket is attached is a conductive sheet having a thermal conductivity of 1 watt/meter·K.