Abstract: A wiring substrate, a film carrier, a semiconductor device made by using the film carrier, and a mounting structure comprising the semiconductor device are disclosed.The wiring substrate comprises:a conductor pattern which has a bonding pad and is formed on the rear surface of an insulating support;at least one of minute through-holes which are provided in a region of the insulating support where the bonding pad is in contact therewith, or which are provided a region of the insulating support where the bonding pad is in contact therewith and in the vicinity of the region, the through-holes running in the direction of the thickness of the insulating support;a conductive passage which is made of a metal material and which is formed in the through-holes that are provided in a region of the insulating support where the bonding pad is in contact therewith; anda bump-like metal protrusion which is formed on the conductive passage and which is protruded from the front surface of the insulating support.