FOCUS MONITORING METHOD OF EXPOSURE DEVICE AND EXPOSURE METHOD USING THE SAME

PROBLEM TO BE SOLVED: To monitor a focus value of an exposure device during production in photolithography. SOLUTION: CD focus curves 2a and 4a of two patterns different in a best focus and a CD focus curve 12a of one pattern deciding a reference of a size are formed. Exposure of an exposure device is set so that an average value of a minimum value 14a and a maximum value 16a of a focus value decided from a common focus depth 7 of the CD focus curves 2a and 4a becomes equal to the best focus 10a which is set in production and a size 12b of the CD focus curve 12a becomes a size requested in production. When sizes 2b and 4b of the CD focus curves 2a and 4a in the respective focus values are measured while the focus value is changed, a calibration curve is obtained from a corresponding relation between a differences 13 of the sizes and the focus value 15a. The focus value 15a of the exposure device can be monitored from the difference 13 of the sizes on a wafer in production. COPYRIGHT: (C)2006,JPO&NCIPI