Junction structure and an electronic device using the electronic device

Object of the present invention is to provide a joint structure having a high joint strength for electronic devices. Engaging a side surface configuration of an electronic device of the present invention is used (10) includes a first metal layer (11) comprising nickel, and forming a first metal layer on the first (11) and comprising gold, tin and nickel second metal layer (12), the second metal layer (12) comprises AuSn eutectic phase.