Conductor pattern forming method, and semiconductor device manufacturing method

A conductor pattern forming method includes forming, on a conductor film, a laminated film including a first layer thinner than the conductor film, a second layer thicker than the first layer, and a third layer thinner than the second layer, which layers are laminated in order from the conductor film side. A first mask is formed from the third layer by dry-etching the third layer using a photoresist mask formed on the laminated film. A second mask is formed from the second layer by dry-etching the second layer using the first mask. The conductor film is exposed by dry-etching the first layer using the second mask. A conductor pattern is formed from the conductor film by dry-etching the conductor film using the second mask.