A PHOTO MASK FOR ESTABLISHING A BEST FOCUS AND METHOD OF ESTABLISHING BEST FOCUS USING THE SAME

摘要

A photomask for setting a best focus and a setting method of the best focus using the same are provided to confirm separation of the best focus and image surface according to CD(Critical Dimension) distribution of a photoresist pattern by exposing the photomask having a plurality of test pattern groups with a different grating distribution and a penetration rate. A test pattern part consists of a plurality of test patterns formed in a matrix shape on a quartz substrate. A first test pattern(110) consists of a plurality of first small patterns and a plurality of second small patterns having 100% of penetration rate which are arranged alternately in parallel to each other. A second test pattern(120) consists of a single small pattern having 6% of penetration rate. A third test pattern(130) consists of a plurality of third small patterns having 100% of penetration rate which are separated with a predetermined distance. A fourth test pattern consists of a plurality of fourth small patterns and a plurality of fifth small patterns having 100% penetration rate which are arranged alternately in parallel to each other. Each small pattern has a grating of a predetermined phase.