The present invention provides a semiconductor device manufacturing method for lowering the technical difficulties of a process forming a horizontal single crystal nanowire and a manufacturing cost, the semiconductor device manufacturing method comprising the steps of: preparing a substrate including a first area and a second area; determining a position at which a nanowire is to be formed on the substrate of the first area and arranging an empty space in which the nanowire is to be filled; exposing a substrate surface of a part adjacent to the first area; causing selective single crystal growth from the exposed substrate surface; and forming a nanowire by a self-aligned method through an etching process within the first area, and removing, from outside the first area, a single crystal growth layer of the remaining areas excluding a part necessary for the wiring of the second area.