Core substrate and method for manufacturing the same, and substrate with built-in electronic component and method for manufacturing the smae

The present invention relates to a core substrate, a manufacturing method thereof, a substrate with a built-in electronic component, and a manufacturing method thereof. According to one embodiment of the present invention, suggested is the core substrate which includes a first insulation layer; and a second insulation layer which is laminated on the upper and lower sides of the first insulation layer and is made of a material with a glass transition temperature which is lower than the glass transition temperature of the first insulation layer. Also, according to another embodiment of the present invention, suggested is the substrate with the built-in electronic component which includes the electronic component which is built in a cavity; and the core substrate which includes the first insulation layer and the second insulation layer which is laminated on the upper and lower sides of the first insulation layer and is made of the material with the glass transition temperature which is lower than the glass transition temperature of the first insulation layer and on which the cavity is formed. The first insulation layer which is filled and flowed in a gap between the electronic component and the cavity fixes the electronic component.