Method of manufacturing wiring substrate

A method of manufacturing a wiring substrate, comprising:

• a first step of providing a tape member on a first surface of a reinforcing substrate, the reinforcing substrate being formed by a material having a coefficient of thermal expansion which is equal to that of the chip component;
• a second step of forming, on the reinforcing substrate, a through opening for accommodating a chip component therein;
• a third step of inserting the chip component in the through opening and providing the chip component on the tape member, the chip component having a main surface on which at least one circuit component is provided, and the chip component being provided on the tape member such that the main surface of the chip component is flush with the first surface of the reinforcing substrate;
• a fourth step of sealing the reinforcing substrate and the chip component with a resin by forming the resin to cover an entirety of a second surface of the reinforcing substrate, said second surface of the reinforcing substrate being opposite to said first surface of the reinforcing substrate;
• and
• a fifth step of removing the tape member and forming a build-up layer having an insulating layer and a wiring layer stacked on a surface from which the tape member is removed such that the build-up layer covers the main surface of the chip component and the one surface of the reinforcing substrate.