| abstract |
The present invention provides a wiring board, a semiconductor device, and a manufacturing method thereof with high density and low manufacturing cost with high connection reliability. The present invention provides a substrate comprising: a substrate coated with an insulating layer having an electrode and a hole for exposing the electrode; A wiring made of a Cr or Ti layer which is connected to the electrode and brought into close contact with the insulating layer, and a Cu layer adhered to the Cr or Ti layer; A protective film covering the wiring and provided with another hole for soldering; And a solder for external connection which is mounted on the both side holes and diffused into the Cu layer to form an alloy and connected to the Cr or Ti layer as it reaches the Cr or Ti layer. |