METHOD FOR MEASURING ALIGNMENT MARKS

A method for measuring alignment marks is provided to increase the yield of the semiconductor device by improving the alignment-accuracy. The first layer(200) is formed on a semiconductor substrate(100). The first groove patterns(203) for the first alignment marks according to the first patterning are generated by patterning the first layer. The second layer(300) producing the first alignment mark(301) filling up the first groove patterns on the first layer is evaporated. The second groove patterns(303) for the second alignment marks are arranged in location between the first alignment marks by patterning the second layer. The second alignment mark(401) are generated by depositing the third layer filling up the second groove patterns. The alignment signal in which the detection about the first and second alignment marks is included is measured by performing the multiple focus measurement.