Electronic circuit device.

摘要

An electronic circuit device includes a substrate (513), a wiring layer (514) formed on the surface of the substrate (513), a bump (512) formed on the wiring layer (514), and a micro electronic element (511) formed on the bump (512), wherein solid-phase diffusion bonding is performed at least between the wiring layer (514) and the bump (512) or between the bump (514) and the micro electronic element (511).