Focus test mask, focus measurement method and exposure apparatus

摘要

This focus test mask is provided with a test pattern that is projected onto a wafer via a projection optical system. This test pattern includes: a plurality of line patterns that are lined up in a direction of measurement; phase shift sections that are provided in areas adjacent to each of the plurality of line patterns and that are used to shift the phase of light passing through; and reference patterns that are used to obtain an image that forms a reference when the shift in the line pattern image is measured. Spaces between the plurality of line patterns are set at a size that allows each line pattern to be regarded as equivalent to being isolated lines.