Patent ID: 8373288

Claim:
An alignment mark formed by using a first mask used in forming a memory cell pattern on a substrate and formed together with the memory cell pattern, the alignment mark comprising: a first pattern for position detection used for alignment in forming a first wiring pattern; and a first irregular reflection prevention mark that suppresses, when a position detection signal is irradiated as alignment in forming a second wiring pattern further on an upper layer side than the first wiring pattern, irregular reflection of a position detection signal from a second pattern for position detection such that the irradiated position detection signal is not affected by the second pattern for position detection formed by a second mask different from the first mask, wherein the second pattern for position detection is: a pattern formed on a lower layer side than the first pattern for position detection using the second mask having a memory cell pattern same as that of the first mask; and a pattern used for alignment in forming a third wiring pattern formed on a lower layer side than the first wiring pattern.