Patent ID: 7906258

Claim:
A photomask comprising: a light transmitting base having a light blocking film on one surface thereof; a device pattern which is formed of a pattern of a light transmitting portion and a light blocking portion in accordance with the presence and absence of the light blocking film on the light transmitting base and which becomes a circuit pattern of a semiconductor integrated circuit device; and at least one of an alignment mark which is formed of a pattern of a light transmitting portion and a light blocking portion in accordance with the presence and absence of the light blocking film on the light transmitting base and which is utilized for alignment of the photomask during exposure, and a superimposition inspection mark which is formed of a pattern of a light transmitting portion and a light blocking portion in accordance with the presence and absence of the light blocking film on the light transmitting base and which is utilized for superimposition inspection to inspect whether or not the device pattern has been exposed at a correct position, wherein each of the alignment mark and the superimposition inspection mark includes a main mark portion, and first and second auxiliary pattern portions formed along two opposite side ends of the main mark portion, the main mark portion is constituted of one of a space pattern in which a hole is made through the light blocking film and a line pattern in which the light blocking film is left, the pattern having a linear width to be resolved on a photosensitive film formed on a semiconductor wafer, each of the first and second auxiliary pattern portions includes an auxiliary pattern, which is constituted of one of a repeated pattern of a space pattern in which a hole is made through the light blocking film and a repeated pattern of a line pattern in which the light blocking film is left, the repeated pattern having a linear width not to be resolved on the photosensitive film, and a pitch of the repeated pattern is equal to a minimum pitch of the device pattern.