PRINTED CIRCUIT BOARD

PURPOSE: A printed circuit board is provided to prevent the deformation of a substrate due to thermal expansion difference between a chip and the substrate by differently forming the thermal expansion rates of insulation layers. CONSTITUTION: A first insulation layer(20) is formed on the upper side of a core layer(10). The first insulation layer is formed by stacking a plurality of insulation layers with a circuit. The first insulation layer has a preset thermal expansion rate. A second insulation layer(30) is formed on the lower side of the core layer by stacking the plurality of insulation layers with the circuit. The second insulation layer has the thermal expansion rate which is different from the first insulation layer. The thermal expansion rate is in proportion to the circuit area formed on the surface of the first and second insulation layers.