Alignment method, overlay deviation inspection method and photomask

An overlay inspection method for a photomask, comprising:

• forming on a wafer a first device pattern and an alignment mark, using a first photomask having at least the first device pattern and the alignment mark which has a shape equal to or similar to the first device pattern;
• exposing said resist film formed on the wafer to the second photomask according to the alignment mark;
• and
• determining the positioning accuracy of the second photomask with respect to the wafer using the alignment mark.

A photomask comprising:

• a device pattern;
• an alignment mark having a size and a shape equal to or similar to those of said device pattern;
• and
• a deviation inspection mark having a size and a shape equal to or similar to those of said device pattern.

A photomask comprising:

• a device pattern configuration including at least two device patterns having different sizes and shapes;
• an alignment mark including at least two alignment mark elements having different sizes and shapes corresponding to those of the device patterns;
• and
• a deviation inspection mark having a shape including a part of said device pattern configuration.

A photomask comprising:

• a device pattern configuration;
• an alignment mark including a reference pattern and a part of said device pattern configuration;
• and
• a deviation inspection mark having a shape including a part of said device pattern configuration.