Electronic element and making method thereof

The invention is to offer electronic parts and a method of producing the same in which a producing time is shortened, crack or warp are hard to occur, and cost-down can be attained. Core substrates are made by forming a resin or a compound material made by mixing powder-like functional materials with this resin into thin plates, and hardening them. Conductor patterns are formed on at least any of front and back surfaces of the core substrates through any of an evaporation process, an ion plating process, an ion beam process, a sputtering process, and a vapor deposition process, followed by patterning. Half-hardened prepregs are produced by forming the resin or the compound material made by mixing powder-like functional materials with this resin into the thin plates. The prepregs and the core substrates are alternately laminated and laminated layers are made by unifying through a hot pressing.