To make a base material step peak sharp by making the length of a side of a main scale pattern shorter than the average grain size of a metal layer.

A rectangular main scale pattern 2 is formed on a semiconductor substrate 1 with resist. The length of a side of the main scale pattern 2 is made shorter than the average grain size of aluminum, which is a component of a metal layer, acting as an upper layer. Then a metal layer which comprises aluminum is formed on the top surface of the semiconductor substrate 1 including the main scale pattern 2. Although the metal layer comprises a grain, and the surface thereof is uneven, by making the length of the side of the main scale pattern 2 shorter than the average grain size of the metal which is a material of the metal layer, a base material step peak is sharp, and reliability in measurement accuracy of an alignment mark and measurement reproducibility thereof are improved, and the degree of freedom of pattern design following alignment mark reduction is improved.