A metal wire for inspection and an electrode for inspection are formed on a region of a semiconductor substrate where a metal wire and an electrode for external connection are not formed. The metal wire for inspection and the electrode for inspection electrically detect an open failure, a short-circuit failure and a leakage failure of the metal wire and a connection failure between an element electrode and the metal wire. A semiconductor wafer is subjected to an electrical test, so that it is possible to detect the aforementioned failures with good accuracy during a manufacturing process.