Method of manufacturing electronic-component-embedded substrate, electronic-component-embedded substrate, electronic component device, and communication module

A method of manufacturing an electronic-component-embedded substrate in which an electronic component is embedded, the method comprising:

• a power-supplying layer forming step of forming a power-supplying layer on a base;
• an electrode forming step of forming an electrode that has a predetermined pattern and that is to be connected to the power-supplying layer on the power-supplying layer by an electrolytic plating method;
• an electronic-component arrangement step of arranging the electronic component above a surface of the power-supplying layer on which the electrode is formed;
• a sealing step of sealing the electronic component on the power-supplying layer;
• a first-wiring-line forming step of removing the base and forming a first wiring line by patterning the power-supplying layer;
• an insulating-layer forming step of forming an insulating layer such that the insulating layer covers a portion of the first wiring line;
• and
• a second-wiring-line forming step of forming a second wiring line above at least a portion of the first wiring line and a portion of the insulating layer such that the second wiring line crosses, on the insulating layer, a portion of the first wiring line.