In a physical quantity sensor, wirings provided on a projection and a bonding pad form a silicide layer and are electrically connected. The wirings are multilayered films. A noble metal layer covers the projection and contacts the bonding pad to form the silicide layer. A metal layer extends between the noble metal layer and a base substrate. The metal layer, the noble metal layer, an adhesion layer, and an insulating layer are stacked in this order from the base substrate in all areas except for atop the projection.